Influence of cellulose ethers on the kinetics of early Portland cement hydration
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The optimization of size, core content and wall structure allows the properties of the microcapsules to be controlled and used as a delivery system in a wide range of formulations. There are two product families, the S grades and R grades. The S grades are standard iron grades with a purity level of approximately R grades are high-purity iron grades with an average purity of Through a hydrogen reduction process most of the residual carbon and nitrogen have been removed from the iron particle producing a higher purity iron grade which is lower in durometer hardness and lacking the unique onionskin structure.
Cathode slurries produced with Micropure EG solvent have ideal characteristics for coating on aluminum foil and for use in a solvent recovery systems. Produced in a world-class ISO-accredited plant, Micropure EG solvent meets the exacting standards for low color, and low moisture and metal content required by the lithium-ion battery market.
Polyacrylamidopropyltrimonium Chloride. The use of Ashland's synthetic cationic polymers helps formulators to improve deposition of oil soluble materials to the skin from a rinse-off formulation. All are compatible wit a wide range of anionic, nonionci and cationic surfactants. N-Hance SP conditioning polymer is used as a substantive conditioning polymer in rinse-off surfactant systems, such as shampoos, to reduce tangling and improve the wet and dry comb properties of hair after shampooing. It is especially useful for delivering a highly conditioned feel to wet and dry hair.
N-Hance SP can also be added to bath and shower gels to improve skin feel after bathing or showering. N-Hance SP conditioning polymer also functions as a deposition polymer in two-in-one shampoo and body wash systems by forming a coacervate with anionic surfactants, promoting the deposition of silicone, other emollients, or anti-microbial agents such as zinc or selenium onto hair and skin.
Typical use levels are from 0. The cationic charge makes the product substantive to anionic surfaces such as skin and hair. Many of the products in the N-Hance cationic guar product line have a high molecular weight, water-soluble backbone and are effective viscosifiers in aqueous solutions and surfactant-based systems. M-Pyrol solvent, a lower alkyl pyrrolidone, is an extremely powerful and versatile aprotic solvent. With its high boiling point, low vapor pressure and high stability, it is an effective solvent in numerous industry applications and can be used as a co-solvent with water, alcohols and other organic substances.
M-Pyrol solvent is extremely resistant to hydrolysis from pH , even at elevated temperatures. Beyond these limits, hydrolysis to 4- methylamino butanoic acid occurs at a rate dependent on pH and temperature. A large body of chemistry has been developed on the reactions of strong nucleophiles with M-Pyrol solvent.
M-Pyrol solvent is an excellent polymer solvent, paint and photoresist stripper, paint coalescent, industrial cleaner, and extraction solvent. Its N-Methyl 2 pyrrolidone structure is extremely resistant to hydrolysis from pH , even at elevated temperatures. With a gentle, natural renewal from the inside, the skin surface is re-texturized. By enhancing essential water molecules, hydrasources are restored resulting in skin that is visibly more quenched. It helps skin adapt more readily to solar exposure and limit exposure-related damage, preserving its healthy appearance and beauty.
Skin may appear smoother, refreshed and firmer. It comprises a range of hydroxyethylcellulose thickeners that delivers unprecedented process flexibility and quality control to paint manufacturers. The patented technology triggers rapid and complete dispersion in any water-based medium, even under low shear conditions. This allows manufacturers to add HEC in dry form at any point of the manufacturing process, eliminating extra process steps such as the preparation of pre-slurries or dissolutions of HEC, saving operational costs.
The end result is a faster, more efficient, less costly production process. In addition, Natrosol Performax thickeners enhance paint quality and preserve critical performance characteristics, such as efficient thickening, stability, color compatibility and sag resistance. Ashland's Natrosol thickeners have been the leading HEC thickeners for waterborne architectural coatings for more than 50 years. Hydroxyethylcellulose is offered in different viscosity levels molecular weights , particle size distribution and are available as regular HEC or more enzyme resistant HEC.
You also have the choice to use retarded solubly types, which simplify preparation of solutions and incorporation into the final products. This best-in-class, bio-resistant HEC will maintain stability even in the presence of cellulose enzyme produced by microbial activity.
Natrosol B HEC grades for paints and coatings applications are typically glyoxylated R-treated for ease of incorporation. In latex architectural paints, Natrosol B HEC is know for superior color performance, stability, shear-thinning, application properties and sag resistance. Virtually all viscosity grades of Natrosol commonly used in paint and coatings, including Regular, B-types and Natrosol Plus, are also available in a fluidized FPS version. HEC polymer is pre-dispersed in a stabilized aqueous media, creating an easy-to-handle, pourable, pumpable liquid cellulosic thickener.
Natrosol FPS can be easily added to the grind, but is most advantageous when added directly to the let-down stage of paint making, where it readily disperses and incorporates quickly without lumping. FPS is also commonly used as a post-thickener to adjust the final viscosity of finished batches. The first is the standard reaction of alkali-cellulose with ethylene oxide to produce HEC. The second step is a cetyl substitution, which provides the hydrophobic end groups.
The resultant nonionic polymer is purified and dried. HMHEC polymers are unique in that they function as associative thickeners, meaning they not only thicken aqueous systems via chain entanglement and conventional hydrogen bonding, but also via hydrophobe interactions. In solution, hydrophobe groups seek out other hydrophobes, including oils and pigments, forming weak interactions and effectively creating a three-dimensional polymer network.
The hydrophobic modification imparts many unique properties to HMHEC polymers including pseudoplastic shear thinning behavior, high salt tolerance and long-term stability over a very wide pH range 3. In addition to the hydrogen-bonding and chain entanglement, typical of standard HEC, Natrosol Plus is hydrophobically modified and readily forms weak, three-dimensional networks via hydrophobe association.
This associative thickening mechanism provides the best spatter resistance in the industry but does not suffer from the formulation sensitivity typical of synthetic associative thickeners SATs. Natrosol Plus modified HEC is a white, free-flowing powder that is readily incorporated into paints. It is also available as a pumpable liquid as Natrosol Plus fluidized polymer suspension.
It is made by reacting ethylene oxide with alkali-cellulose under rigidly controlled conditions. Purified HEC for personal care and cosmetic applications is typically sold at Solutions of Natrosol HEC are pseudoplastic or shear-thinning. As a result, personal care products formulated with Natrosol HEC dispense rich and thick from the container, but spread easily on hair and skin. Natrosol HEC is easily dissolved in cold or hot water to give crystal-clear solutions of varying viscosities. Furthermore, low to medium molecular weight types are fully soluble in glycerol and have good solubility in hydro-alcoholic systems containing up to 60 percent ethanol.
Natrosol HEC is generally insoluble in organic solvents. Natrosol HEC is used as a binder, bond strengthener, cement extender, coating and optical brightener aid, coating polymer, filtration control additive, green strength enhancer, protective colloid, rebound or slumping reducer, rheology controller and modifier, lubricity and workability enhancer, suspension and stabilization agent, shape retention enhancer and thickener. Natrosol HEC has applications in multiple markets including adhesives and sealants, advanced ceramics, building and construction, ceramics, pottery and porcelain, commercial and institutional, oil and gas technologies, metal castings and foundry, paint and coatings, personal care, pharmaceutical and pulp and paper.
Nexton specialty water-soluble polymers are a family of nonionic additives. Their unique chemistries provide distinctive textures in cement, gypsum- and latex-based products improving workability, cohesiveness and appearance of building material. Nexton products have been developed specifically for masonry systems and tape joint compounds and also find application in gypsum plasters and renders. Omnirez polymer forms tough, clear, glossy films and delivers long-term hold to hair in high humidity conditions. The polymer allows for good sprayability and has good propellant compatibility.
The performance of Omnirez polymer can be optimized by selecting the appropriate additives, neutralizers, packaging and valving. Optimage SF microgel provides both rapid and long-lasting improvement in the appearance of fine lines and wrinkles. It achieves this due to its unique gel-matrix composition, which has an affinity to skin and adapts to wrinkle topology.
This microgel is a patent-pending technology that is soft, silicone-free, pre-dispersed, and robust in formulation. This technology can be used in both anti-aging and "selfie-ready" skin care formulas.
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Applications leave-on skin care. Optiphen HD preservative booster. Diols can influence the overall microbial stability due to their water binding properties. They are widely used in skin care, hair care, wet wipes, toiletries and color cosmetics. With their moisturizing and solubilizing properties, they are considered to be multifunctional. Their neutral smell and wide pH tolerance makes them suitable for many applications.
Optimizing the delivery of non-alcohol preservatives is essential to the viability of next-generation preservative systems. The delivery system serves to maximize preservative efficacy without interfering with or destabilizing cosmetic formulations such as emulsions. All of the preservative products offered within the Optiphen P platform address today's demands for cost-efficient preservatives that follow natural ingredient trends. Optiphen DLP up to 6. Phenoxyethanol and Caprylyl Glycol. An additional booster increases the broad spectrum activity against micro-organisms.
It can be used in a variety of cosmetic formulations. The excellent pH compatibility allows use in acidic and slightly alkaline formulations. It is applicable for use in a variety of rinse off personal care preparations such as shampoos and conditioners. It is also well suited for high-quality care-cosmetics like creams, emulsions, wet wipe systems and gels.
It is also well suited for high-quality care-cosmetics like creams, emulsions, lotions, and gels. The natural movement continues to drive consumer buying habits, so it's no surprise that marketers also harbor a preference for all things green. That's why Ashland's nature-identical preservatives are ideal solutions for products aimed at the Eco-aware consumer.
These preservatives support a variety of natural personal care products. Optiphen BD is not sold in NA. Sodium Benzoate and Potassium Sorbate. Effective against gram-positive and gram-negative bacteria, yeast and mold, it offers excellent heat stability, works across a wide pH window and is easily solubilized in water. Propylene Carbonate and Dehydroacetic Acid.
When used at higher dosages full protection can be achieved. It provides comprehensive antimicrobial protection in aqueous and emulsion-type personal care formulations and incorporates an optimized delivery system to maximize the actives efficacy usually without interfering or destabilizing cosmetic formulations, such as emulsions.
These methylisothiazolinone-based preservatives can be used in products that are typically considered difficult to preserve with conventional preservatives. Effective against gram-positive and gram-negative bacteria, yeast and mold, they offer excellent heat stability, work across a wide pH window and are easily solubilized in water. Balanced and synergistic, it provides broad-spectrum protection and is compatible with many other cosmetic ingredients. Approved for use in most countries, Optiphen MIT Ultra and other classic preservatives, are effective at low doeses and can be used to bolster other preservatives.
Aqua Water and Methylisothiazolinone. Phenoxyethanol and Benzoic Acid and Dehydroacetic Acid. Phenoxyethanol and Caprylyl Glycol and Sorbic Acid. Positioned for anti-aging facial products, it helps promote long-term skin benefits and natural protection from environmental aggression. PVP K-series. Polyvinylpyrrolidone is a hygroscopic, amorphous polymer supplied as a white, free-flowing powder or a clear aqueous solution. Available in several molecular weight grades, they are characterized by K-value, and used in a great variety of applications.
Polyvinylpyrrolidone can be plasticized with water and most common organic plasticizers. High polarity and the resultant propensity to form complexes with hydrogen donors, such as phenols and carboxylic acids, as well as anionic dyes and inorganic salts. Dispersancy, where components in a mixture are uniformly distributed through the use of polyvinylpyrrolidone. Hydrophilicity, where the substantial water solubility of polyvinylpyrrolidone is its dominant feature and frequently a factor along with other properties valuable to numerous applications.
Adhesion, taking advantage of the higher molecular weight polyvinylpyrrolidones formulating in aqueous media, then evaporating sufficient water to generate a solid product for the desired application. Cohesivity, where cohesive strength is achieved through a variety of dry blending and granulation techniques. Polyvinylpyrrolidone is cross-linkable to a water insoluble, swellable material either in the course of vinylpyrrolidone polymerization, by addition of an appropriate multifunctional comonomer or by post-reaction, typically through hydrogen abstraction chemistry.
Hair Care Inks and Printing. Polymers in the four ranges of vinylpyrrolidone content 30, 50, 60 and 70 percent , are produced in ethanol or isopropanol. Water and Propanediol and Pentapeptide Trifluoroacetate. This biofunctional, an anti-wrinkle pear seed extract, shows consumer perceivable wrinkle reduction and significant improvement in skin surface appearance.
Our technical team will be happy to discuss further whether Perluxan extract or one of our other products is the best product for you.
In the second part of the study, human subjects submitted blood samples for analysis. A study published in Phytochemistry measured the fecal calprotectin content of subjects who had consumed a modified hops extract. This biomarker was used as a surrogate for evaluation of gastrointestinal inflammation. Supplied as white powders, the complexes release hydrogen peroxide on contact with water or saliva in the mouth to deliver hydrogen peroxide, resulting in brighter and whiter teeth.
These unique complexes are stable in a wide range of solvents and provide excellent substantivity, bioadhesion, film-forming and formulation thickening. Features and Benefits: releases hydrogen peroxide for oxidative whitening are supplied as very stable powders act as excellent film formers, tablet binders or disintegrants provide a range of solubilities, substantivity and viscosities Applications: teeth whiteners Grades: grades base polymer K PVP K PVP XL crosslinked PVP.
It is a water-miscible polar aprotic solvent with high interfacial activity. It is used as a drug solubilizer and penetration enhancer in human and animal parenteral dosage forms. Preservative system: sodim benzoate Recommended use level: 0. Baobab seed extract rich in plant small RNAs and associated with improved epigenetic homeostasis in aging skin. Water and Glycerin and Hydrolyzed Soybean Extract.
The polymer can be effectively used to bind and remove stains through hydrogen bonding with chemical compounds. It is commonly used to enhance the solubility of active pharmaceutical ingredients and increase bioavailability of poorly soluble drugs through the formation of melt-extruded or spray-dried solid dispersions. Soluble in water and in many organic solvents, Plasdone S polymer is substantive, and acts as a film-former. It is also used as a tablet binder for denture cleaning tablets. Ashland offers a comprehensive range of Plasdone povidones PVP.
Plasdone povidones are a family of water-soluble polymers based on N-vinylpyrrolidone that combine a unique set of properties for application in a wide variety of dosage forms. Plasdone povidones are commonly used as binders for the development of tablet formulations, whether manufactured by wet granulation, dry granulation or direct compression. Plasdone K polymers are used in solid-dispersion formulations to enhance the solubility of active pharmaceutical ingredients and increase bioavailability.
Ashland has a full line of solvent and water-based bonding adhesives for single-ply roofing membranes and industrial grade contact adhesives. VOC-compliant versions of many adhesives are available. The systems distinguish themselves with excellent specific adhesion to thermoset and thermoplastic materials as well as to coated metals. Amongst the advantages in plastic bonding and repair applications they offer a well-balanced profile of easy application, gap filling and optimized trimming sanding properties. Greatly enhanced impact toughness sets it apart from other commercial two-component plastic bonding and repair systems.
It is optimized for single use on its own or in conjunction with other stabilizers, to offer a highly effective means of preventing non-biological haze in all types of beer. Non-biological haze formation results primarily from hydrogen bonding between haze-producing proteins and the polyphenol constituents of beer. To achieve colloidal stability, it is necessary to reduce these protein-pholyphenol complexes or prevent them from forming.
Polyclar 10 beer stabilizer complexes with specific polyphenols in beer via hydrogen bonding and is then removed during filtration. The bonding occurs between the carbonyl groups of Polyclar 10 beer stabilizer and the hydroxyl groups of polyphenols. It is an optimized composite of purified food-grade carrageenan and specially modified polyvinyl polypyrrolidone PVPP making it the ideal upstream, single-addition product for stabilization protection against chill haze and permanent haze. Non-biological haze formation results primarily from the hydrogen bonding between haze-producing proteins and the polyphenol constituents of beer.
Non-microbiological products NMPs act as templates on which these protein-polyphenol complexes may attach, thereby accelerating haze development in beer. Kappa-carrageenan, a hydrocolloid extracted from red seaweed, is very effective at reducing the size of NMPs in wort. These comprise protein, polyphenol, polysaccharide and other materials. Polyvinyl polypyrrolidone, or crosslinked PVP, is a synthetic polymer that specifically binds to haze-producing polyphenols.
It complexes with specific polyphenols in beer via hydrogen bonding and is then removed during filtration. To achieve colloidal stability in beer, it is necessary to reduce these protein-polyphenol complexes, or prevent them from forming. Polyclar Brewbrite beer stabilizer does both as it reduces the size of NMPs in the wort and removes polyphenols. This product is designed to be used in breweries with regenerative filter systems. It is optimized for regeneration use, either on its own or in conjunction with other stabilizers, offering a highly effective means of preventing non-biological haze in all types of beer.
If offers the following key benefits: regeneration-grade PVPP, requiring a dedicated secondary regeneration filter effective and highly selective removal of haze-producing polyphenols protection against chill haze and permanent haze development prevents oxidation of flavonoids, which contributes to harsh, astringent and stale flavors in beer.
It provides all the benefits of Polyclar 10 single-use beer stabilizer in a low-dust version. The granules are considerably larger than Polyclar 10 single-use beer stabilizer, very low-dusting and produce a cleaner slurry for addition to beverage tanks. Extremely easy to handle and disperse, Polyclar Granules single-use, low-dust beer stabilizer requires just a few minutes of contact time for selective hydrogen bonding to remove undesirable tannoids.
This fast-wetting characteristic is due to its large surface area, which helps to accelerate the slurrying process and create efficient dispersion and hydration. It benefits from the synergism between these two components by extending beer shelf life and filtration.
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A dual-action stabilizer, it offers highly effective reduction of both haze-forming polyphenols and haze-forming proteins. The use of silica xerogel is the most common method of reducing haze-forming proteins. The gel adsorbs the proline-rich, haze-forming protein onto its surface. The inclusion of PVPP in the admixture of Polyclar Plus single-use, balanced beer stabilizer provides efficient and highly selective removal of haze-producing polyphenols, thus preventing the formation of insoluble protein-polyphenol complexes responsible for chill and permanent haze.
Polyclar Super R regeneration-grade beer stabilizer has low swelling characteristics in aqueous conditions and high adsorption capacity for haze-forming polyphenols making them ideal for high-volume-throughput filter runs. In addition, Polyclar Super R regeneration-grade beer stabilizer achieves high efficacy of polyphenol removal through optimized morphology and particle size and its ability to withstand repeated regeneration cycles high mechanical strength.
Brewers can achieve a high degree of stability and clarity from optimized dosage of PVPP, and yet, at the same time, it can be regenerated and used for repeated cycles. Polyclar Super R regeneration-grade beer stabilizer provides a robust solution for use with most PVPP-regeneration filter systems to preserve the quality and character of beer after packaging. Polyclar single-use stabilizers are used preventively or remedially to specifically adsorb polyphenolic materials and their monomeric precursors.
Crospovidone provides rapid disintegration and dissolution to oral solid dosage forms. Polyplasdone crospovidone particles are granular and porous compared with other superdisintegrants. The high surface area combined with unique chemistry results in high interfacial activity that enhances the dissolution of poorly soluble drugs in a way that is not possible with other disintegrant technologies.
A crosslinked PVP, this, nonionic, water-insoluble but swellable homopolymer is available in several grades XL, XL differentiated by particle size. Complying with USP, European and Japanese pharmacopeia specifications for Crospovidone, Polyplasdone polymer act as tablet disintegrants. It may reduce the breakdown of sucrose from food through l-arabinose action on the sucrase enzyme and may support control of insulin in healthy people through the addition of chromium.
L-arabinose is a monosaccharide found in nonstarch carbohydrate plants like corn. In vitro and animal studies have indicated that the compound may inhibit sucrase action and consequent digestion of sucrose. A dose-response study showed a reduced serum glucose level and serum insulin response to sucrose consumption, indicating that the addition of l-arabinose blocked absorption of the sugar. FDA concludes, however, that the existence of such a relationship between chromium picolinate and either insulin resistance or type 2 diabetes is highly uncertain.
The cetearyl and behenyl alcohols function as an emulsion stabilizer, binder, viscosity-increasing agent and opacifying agent. The hydroxyethyl cetearamidopropyldimonium chloride is the quaternary compound providing antistatic properties and super-conditioning benefits. ProLipid lamellar gel has superior conditioning benefits in both leave-on and rinse-off products. It is suitable for treatment applications targeting damaged and chemically treated hair.
In rinse-out applications, it delivers a soft feel and allows for effortless wet and dry combing. In addition, they enhance the performance of cosmetic formulations and can be used to develop stable lamellar gel networks with a wide range of rheologies and sensory attributes depending on the type of auxiliary ingredients present. This patent-pending technology may help hair defense, as demonstrated by in vitro and ex vivo studies, by helping maintain the level of antioxidant protein expression in the hair follicles.
In addition, it may assist the scalp to limit hair cell death in stress conditions and may aid in the preservation of hair color. It therefore results in the appearance of healthy, fuller, younger-looking hair. Preservative system: sodium benzoate. Water and Butylene Glycol and Dimer Tripeptide Oryza sativa is listed on the Chinese list of recognized ingredients in Ministry of Health. Water and Glycerin and Hydrolyzed Rice Protein. Preservative system: sodium benzoate, potassium sorbate. Some of our patented formulations have been specifically designed for low migration and metalized film applications.
PureSeal water-based cold seals are natural rubber latex, synthetic or hybrid blends. PureSeal heat-activated adhesives are synthetic emulsions based on styrene acrylic polyurethane and vinyl acetate emulsions, formulated to balance hot tack, seal strength and block resistance. PureSeal cold seals and heat-activated adhesives can be formulated to perform on various substrates and at specific adhesion values, FDA regulations, sterilization methods and other compounded organoleptic requirements.
They can be used in gravure, flexographic, roll, rod and pattern coating applications. Whatever your needs, Ashland has a product for you. We can customize our products to meet your specific requirements. This adhesive was specifically designed as a fast cure system with final bonds obtained within 48 hours under ambient conditions without the need of a hot room post-cure. Composed of two components, it is used in food and industrial flexible packaging applications that require an aliphatic polyurethane chemistry to prevent the formation of aromatic amine extractables or require high resistance to UV weatherability.
Purelam has been formulated to exhibit exceptional performance when applied to metalized films or aluminum foil. Purelam is FDA compliant and is typically used in flexible packaging markets for products such as snacks, meats, confectionery and cheeses. From overprint varnishes to adhesives, we offer a wide range of products to fit the most demanding applications including high scuff resistance, low migration and chemical resistance. They are specifically formulated to provide excellent coefficient of friction COF stability, without the need to add an external slip additive package.
Purethane adhesives have very low odor retention. They can be used either as a one-component or two-component systems for applications where moderate to high levels of moisture, temperature, and chemical resistance are required. Water and Butylene Glycol and Dipeptide It helps protect skin from environmental stresses and prevents loss of skin resiliency. Preservation system: preservative-free Recommended use level: 0. Blood Safety. Rad-Sure is available in two types: Gamma and X-Ray.
Gamma is compatible with Cesium or Cobalt radiation sources and X-Ray is compatible with x-ray irradiators that utilize x-rays generated from kVp sources that are filtered through 0.
When attached to blood products, Rad-Sure blood irradiation indicators show whether the blood products have been irradiated. Product Features: indicators can now be stored at room temperature! FDA listed medical device. For more information about Rad-Sure or how to order, contact us. The unique design features three windows that, once exposed, can transfer from the illumination container to the final storage containers, following the path of the product.
They should not be used as dosimeters to measure the dose delivered by the illuminator. These products are easy to use, shear-tolerant, shear-thinning and effective at low use levels. The performance characteristics and benefits of the polymers allow formulators to develop a range of efficacious and appealing personal care products.
A unique blend of phytosterols and phytostanols derived from coniferous trees, which is proven to block the absorption of cholesterol from the gastro-intestinal tract. Phytosterols and phytostanols compete with cholesterol for absorption in the small intestine. This, in turn, reduces dietary cholesterol absorption.
Overuse of sterols, however, leads to high levels of sterols in the blood, which have been associated with atherosclerosis. Phytostanols, like phytosterols, reduce cholesterol absorption but do not increase blood sterol content. This product is not intended to diagnose, treat, cure, or prevent any disease.
Phenoxyethanol and Iodopropynyl Butylcarbamate. This tried and true preservative delivers efficient antimicrobial power to a wide variety of personal care products. Balanced, synergistic and boasting broad-spectrum protection, Rokonsal J preservative is compatible with many other cosmetic ingredients. Approved for use in most countries, and available for sale in EMEA, this preservative is effective at low doses and can also be used to bolster other preservatives.
This tried and true classic preservative delivers efficient antimicrobial power to a wide variety of personal care products. Balance, synergistic and boasting broad-spectrum protection, Rokonsal KS-4 preservative, approve for use in most countries and is available for sale in EMEA, is effective at low doses and can be used to bolster other preservatives. This tried and true classic delivers efficient antimicrobial power to a wide variety of personal care products. Balanced, synergistic and boasting broad-spectrum protection, Rokonsal LJ-1 is compatible with many other cosmetic ingredients.
It's sold in EMEA and approved for use in most countries, Rokonsal LJ-1 preservative, like other classic preservatives, is effective at low doses and can also be used to bolster other preservatives. Approved for use in most countries, Ashland's family of classic preservatives are effective at low doses and can be used to bolster other preservatives. The Giant Kelp is sustainably sourced and eco-harvested from the wild off the coast of California. The process is solvent-free, consumes minimal energy and creates virtually no waste. Regeneration, nutrition and barrier functions are the three properties of the Giant Kelp seaweed.
The condurango name comes from condur-angu, a condor vine used by the large condor eagles as anti-venom against snake bites. Condurango is a bitter herb known worldwide for its detoxifying properties. It is commonly used in nutraceuticals and homeopathy. The bark is rich in cinnamate derivatives, which are known for their anti-inflammatory properties.
Stress is universally ranked as a key negative influence on wellbeing. Many relate their stressful lives with negative changes to their skin appearance. Additionally, increased exposure to pollution has resulted in health-conscious consumers looking for anti-stress solutions. Specialty and Industrial Coatings Intermediates and Solvents. In addition to their excellent solvency, our engineered solvents are formulated for low VOC and low toxicity.
They are effective replacements for methylene chloride, acetone, MEK and halogenated solvents. These products produce a well defined amount of homogeneously distributed microscopic air bubbles in building mortars. This reduces the density of the wet mortars and improves workability. In addition, the small air void system can improve freeze-thaw durability while minimally influencing the final strength. Food Packaging Tapes and Labels. Sorez HS polymers forms a water-soluble film on most surfaces that reduces the ability of soil to stick enabling easier cleaning.
In addition, the polymer film helps enhance the appearance of freshly cleaned surfaces. It is a two-component system compatible with typical coating processes. It delivers good lithium ion permeability and minimizes negative effects on cell electrochemistry cycling or rate study. As a leading supplier of a wide range of specialty ingredients, Ashland provides binders to the lithium ion battery LiB industry. A primary purpose of the ceramic-coated separator in lithium ion batteries is to increase temperature tolerance and to provide mechanical stability.
Heat shrinkage of the separator film can profoundly affect the lifespan and safety of lithium ion batteries. The ceramic coating on the separator provides a safety benefit to the cell by providing a heat-resistant layer. As a leading supplier of a wide range of specialty ingredients, Ashland has complemented its range of binders to include dispersants for the lithium ion battery LiB industry. Soteras MSi binder is a unique water-based binder for high-capacity silicon-based anodes in lithium ion batteries.
Combined with these silicon technologies, the Soteras MSi binder helps lithium ion battery cell producers increase capacity by up to 30 percent. Flexible and strong, Soteras MSi binder is compatible with current industry processing requirements. The Soteras MSi binder offers good electrochemical stability, enabling producers to design batteries with a wider voltage range than they can with conventional binders. The binder also has good slurry properties, which facilitate smooth coated surfaces on the collector and help prevent battery failure.
The binder of choice for silicon-containing anodes. Soteras MSi binder has better capacity retention in all three types of silicon-based anodes. The Soteras MSi binder also outperforms the conventional binder at high charge rates. And its superior adhesion contributes to longer cycle life. The Soteras MSi binder is a two-component system, added at a powder to liquid ratio. Suggested dosage is 2. The resulting gels have good shear, temperature and UV-A radiation stability. Sterin provides positive visual verification that the insects have been irradiated to the specified minimum dosage.
Ashland has been manufacturing irradiation indicators for over 25 years that are used around the globe. When attached to containers containing insects, Sterin irradiation indicators show whether the insects have been irradiated. Product Features: Sticks to the inside of the container Easy to use: just peel, stick, irradiate, and read Reduces operator errors by providing a positive, visual verification of irradiation Enhances quality assurance Meets cGMP requirements Sterin is available for doses of 70 Gy, Gy, Gy, and Gy.
Contact us for other doses. For more information on Sterin or how to order, contact us. They should not be used as dosimeters to measure the dose delivered by the irradiator. HEC is commonly considered as a fluid-loss additive. Hydroxycarboxylic Acids. The hydroxycarboxylic acids are well known for their antioxidant and sequestering properties that benefit cement-slurry performance.
The antioxidant property improves the temperature stability of soluble compounds such as fluid-loss additives. Commonly used hydroxycarboxylic acids and their derivatives are citric acid, tartaric acid, gluconic acid, glucoheptonate, and glucono-delta-lactone. The commonly used hydroxycarboxylic acids are generally derived from naturally occurring sugars. Organophosphonates, with a few exceptions, are the most powerful retarders used in cement. These materials are not widely used in well-cementing applications because of the low concentration required, difficulty of accurate measurement, and sensitivity to concentration.
Synthetic Retarders. The term synthetic retarder is a misnomer in that the previously mentioned retarding compounds are all, in effect, man-made. However, the term synthetic retarder has been applied to a family of low-molecular-weight copolymers. These retarders are based on the same function groups as those of conventional retarders e. Two common synthetic retarders are maleic anhydride and 2-Acrylamidomethylpropanesulfonic acid AMPS copolymers. Inorganic Compounds. The retardation mechanism of inorganic compounds on cement hydration is different from that for the previously discussed retarders.
At higher temperatures, the borate is a less-powerful retarder than at lower temperatures; however, it exerts a synergistic effect with other retarders such as lignosulfonates, whereby the combination provides better retardation than either retarder alone. ZnO is a strong retarder when used alone. It is normally used for the retardation of chemically extended cements. Salt as a Retarder. The gelation is evident in the thickening-time viscosity profile of saturated salt slurries by a sudden increase in Bearden units of consistency that then levels off before set. Saturated salt slurries are useful for cementing through salt domes.
They also help protect shale sections from sloughing and heaving during cementing and aid in preventing annular bridging and the lost circulation that could result. Saturated salt cements are also dispersed, and salt reduces the effectiveness of fluid-loss additives. In many parts of the world, severe lost circulation and weak formations with low fracture gradients are common. These situations require the use of low-density cement systems that reduce the hydrostatic pressure of the fluid column during cement placement.
Consequently, lightweight additives also known as extenders are used to reduce the weight of the slurry. There are several different types of materials that can be used. These include physical extenders clays and organics , pozzolanic extenders, chemical extenders, and gases. Any material with a specific gravity lower than that of the cement will act as an extender. These materials, in general, decrease the density of cement slurries by one of three means. The pozzolanic and inert organic materials have a lower density than cement and can be used to partially replace cement, therefore lowering the density of the solid material in the slurry.
In the case of the physical and chemical extenders, they not only have a lower density but also absorb water, thus allowing more water to be added to the slurry without producing free fluid or particle segregation. The gases behave differently in that they are used to produce foamed cements that have exceptionally low density with acceptable compressive strengths.
In many lightweight slurries, it is common to use a combination of the different types of material. Pozzolan slurry designs almost always incorporate bentonite, and gases generally have a chemical extender to stabilize the foam. Lightweight additives also increase the slurry yield and can result in an economical slurry. Physical Extenders. These are particulate materials that function as cement extenders by increasing the water requirements or by reducing the average specific gravity of the dry mix.
There are two general classes of materials that fall into this category: clays and inert organic materials. The most commonly used clay material is bentonite, although attapulgite is also used. The commonly used inert organic materials are perlite, gilsonite, ground coal, and ground rubber. Bentonite Gel. The montmorillonite content of bentonite is the controlling factor in its effectiveness as an extender; hence, it is one of two extenders that are covered by an API specification.
Bentonite can be added to any API class of cement and is commonly used in conjunction with other extenders. Bentonite is used to prevent solids separation, reduce free water, reduce fluid loss, and increase slurry yield. It may be dry-blended with the cement or prehydrated in the mixing water. Laboratory testing is advised to determine the proper gel concentration and mixing procedure for prehydrated bentonite.
Tech grade or "mud gel" should not be substituted for cement-grade bentonite. Lignosulfonate is commonly used as a dispersant and retarder in high-gel cements to reduce the slurry viscosity. Attapulgite Salt Gel. This is a more effective extender than bentonite in seawater or high-salt slurries, but it is not regulated or does not have a specification. It produces many of the same effects as bentonite, except that it does not reduce fluid loss. A disadvantage of attapulgite is that because of the similarity of the fibers to those of asbestos, its use has been prohibited in some countries.
Granular forms are available that may be permitted as a replacement. Expanded Perlite. Expanded Perlite is a siliceous volcanic glass that is heat-processed to form a porous particle that contains entrained air. Because of its low crush strength, the water requirement for perlite-containing slurries must be increased to allow for slurry compressibility under downhole conditions. Volume loss must also be taken into effect in fill-volume calculation. This is an asphaltic material, or solid hydrocarbon, found only in Utah and Colorado.
It is one of the purest naturally occurring bitumens. The low densities obtainable with gilsonite result from its low density 1. Because gilsonite is an organic material, it is highly buoyant and will float out of the slurry unless inhibited. Crushed Coal. Crushed coal is used for the same purposes as gilsonite i. Its density is slightly higher 1. The addition of bentonite to prevent separation is normally not required.
Ground Rubber. This is a low-cost alternative to gilsonite and may be used in similar applications. The density of ground rubber is slightly higher 1. The physical properties are more variable than gilsonite and are dependent upon material source. One major advantage of ground rubber is its low cost. At present, there are no environmental issues with ground rubber when utilized in a cement system. A number of pozzolanic materials are available for use in producing lightweight cement slurries.
These can be either natural or artificial and include fly ash, DE, microsilica, metakaolin, and granulated blast-furnace slag. In comparison with other additives, pozzolanic materials are usually added in large volumes. Fly ash, for example, can be mixed with cement in ratios of fly ash to cement that range from to , based on an "equivalent sack" weight that is, where a sack of fly ash has the same absolute volume as that of a sack of cement. Pozzolanic materials have a lower specific gravity than that of cement, and it is this lower specific gravity that gives a pozzolanic-Portland-cement slurry a lower density than a Portland-cement slurry of similar consistency.
Depending on the density, pozzolanic cements also tend to give a set cement that is more resistant to attack by formation waters. Fly Ash. Fly ash is by far the most widely used of the pozzolanic materials. There is, however, a need for a third category, based on the performance of different fly ashes. In reality, there is a much greater relationship between CaO content and performance. Fly ashes are generally composed of amorphous glassy particles that are spherical in shape. It is this fly ash that is covered by the API specifications.
The major advantages of the Class F fly ash are its low cost and abundance worldwide. The performance characteristics of a Class F fly ash vary little from batch-to-batch from a given source. This produces significant variations in performance characteristics, and because of this, different sources of Class F fly ashes should be tested before use. Specific gravities also must be determined. Some power plants produce Class F fly ashes with a high-carbon content because of poor burning. These should be avoided for oilwell cementing because they can cause severe gelation problems.
The use of Class C fly ash, as an extender for well cementing, is relatively limited. This is, in part, because of the limited availability of Class C fly ash and the considerable variability that exists not only between sources but also to a large extent between batches from a given source. Microspheres are used when slurry densities from 8. They are hollow spheres obtained as a byproduct from power generating plants or are specifically formulated. The byproduct microspheres are essentially hollow fly-ash glass spheres. They are present, typically, in Class F fly ashes, but usually in small amounts.
However, they are obtained in substantial quantities when excess fly ash is disposed of in waste lagoons. The low-density hollow spheres float to the top and are separated by a flotation process. These hollow spheres are composed of silica-rich aluminosilicate glasses typical of fly ash and are generally filled with a mixture of combustion gases such as CO 2 , NO x , and SO x. The synthetic hollow spheres are manufactured from a soda-lime borosilicate glass and are formulated to provide a high strength-to-weight ratio—they are typically filled with nitrogen. The synthesized microspheres provide a more consistent composition and exhibit better resistance to mechanical shear and hydraulic pressure.
The primary disadvantage of most microspheres is their susceptibility to crushing during mixing and pumping and when exposed to hydrostatic pressures above the average crush strength. This can lead to increased slurry density, increased slurry viscosity, decreased slurry volume, and premature slurry dehydration. However, crushing effects can be minimized by the suitable choice of microspheres. These effects can be predicted and can be taken into account in slurry design calculations to produce a slurry having the required characteristics for the well conditions.
Lightweight systems incorporating microspheres can provide excellent strength development and can help control fluid loss, settling, and free water. Microsilica, also known as silica fume, is a finely divided, high-surface-area silica that can be obtained as a liquid or powder. In the powder form, it can be either in its original state, densified, or pelletized. Microsilica typically has a specific gravity of approximately 2. Microsilica particles are also considered to impart beneficial physical properties to the slurry. Because of their fineness, they are believed to fill in the voids between the larger cement particles, resulting in a dense, solid matrix, even before any chemical reaction between the cement particles has occurred.
The physical and chemical properties of the microsilica make it very useful for a variety of applications other than as an extender. These include compressive-strength enhancement for low-temperature lightweight cement, thixotropic properties for squeeze cementing, lost-circulation, gas migration, and a degree of fluid-loss control. The one disadvantage of microsilica is the cost.
Originally considered to be a waste product, with its increased usage in the construction industry over the last decade, it has become more of a specialty chemical. Also, with fluctuations of supply and demand, there is a question of having a constant supply of a good source of the product. Diatomaceous Earth. DE is a natural pozzolan composed of the skeletons of microorganisms diatoms that were deposited in either fresh water or seawater. Several materials are effective as chemical extenders.
In general, any material that can predictably accelerate and increase the concentration of the initial hydration products is effective as a chemical extender. Sodium Silicate. This is the most commonly used chemical extender for cement slurries. Sodium silicate is five to six times as effective as bentonite on an equivalent concentration basis. Unlike the physical or pozzolanic extenders, sodium silicate is highly reactive with the cement. Sodium silicate is available in both dry and liquid forms, making it readily adaptable to onshore and offshore applications.
The solid form is sodium metasilicate Na 2 SiO 3 , and it is typically dry-blended with the cement at a concentration of 1 to 3. It is not as effective if dissolved directly in the mix water unless CaCl 2 is dissolved in the water first. If a liquid system is desired, it is better to use the liquid form. Liquid sodium silicate is normally used in seawater applications at a concentration of 0.
The two main advantages of sodium silicates as extenders are their high yield and low concentration of use. For improved bonding applications, where increased expansion 0. Foamed cement is a mixture of cement slurry, foaming agents, and a gas. Foamed cement is created when a gas, usually nitrogen, is injected at high pressure into a base slurry that incorporates a foaming agent and foam stabilizer. Nitrogen gas can be considered inert and does not react with or modify the cement-hydration-product formation. Under special circumstances, compressed air can be used instead of nitrogen to create foamed cement.
In general, because of the pressures, rates, and gas volumes involved, nitrogen-pumping equipment provides a more reliable gas supply. The process forms an extremely stable, lightweight slurry that looks like gray shaving foam. When foamed slurries are properly mixed and sheared, they contain tiny, discrete bubbles that will not coalesce or migrate. Because the bubbles that form are not interconnected, they form a low-density cement matrix with low permeability and relatively high strength.
Virtually any oilwell-cementing job can be considered a candidate for foamed cementing, including primary and remedial cementing functions onshore and offshore, and in vertical or horizontal wells. Although its design and execution can be more complex than standard jobs, foamed cement has many advantages that can overcome these concerns. Foamed cement is lightweight, provides excellent strength-to-density ratio, is ductile, enhances mud removal, expands, helps prevent gas migration, improves zonal isolation, imparts fluid-loss control, is applicable for squeezing and plugging, insulates, stabilizes at high temperatures, is compatible with non-Portland cements, simplifies admix logistics, enhances volume, has low permeability, is stable to crossflows, and forms a synergistic effect with some additives, which enhances the property of the additive.
The disadvantage of foamed cement is the need for specialized cementing equipment both for field application and for laboratory testing. Weighting agents or heavyweight additives are used to increase slurry density for control of highly pressured wells. The main requirements for weighting agents are that the specific gravity is greater than the cement, the particle size distribution is consistent, they have a low water requirement, they are chemically inert in the cement slurry, and they do not interfere with logging tools.
Hematite Fe 2 O 3. This is the most commonly used weighting agent. Hematite is a brick-red, naturally occurring mineral with a dull metallic luster. The specific gravity of hematite ranges from 4. Ilmenite FeO TiO 2. This is not as commonly used as hematite, although it has some advantages over hematite. It resembles magnetite in appearance but has only a slightly magnetic character. The specific gravity ranges from 4. Hausmannite Mn 3 O 4. Hausmannite is being used increasingly because of its unique properties that address many of the disadvantages encountered with the other weighting agents.
Hausmannite is a dark brownish-black material that is a byproduct mineral from the processing industry. The specific gravity range or Mohs hardness has not been well established. Because the average particle size of hausmannite is much smaller than that of cement, it allows the material to fit within the cement pore matrix, displacing entrained water, resulting in a lower viscosity and significantly more-stable slurry. The main disadvantage is that it is not readily available in all geographic regions, so the additional shipping cost can make it cost-prohibitive.
Barite BaSO 4 Barite is not normally used in cementing as a weighting agent because of its high surface area and high water demand. It is a soft, light gray, naturally occurring nonmetallic material. The specific gravity ranges from approximately 4. Dispersants, also known as friction reducers, are used extensively in cement slurries to improve the rheological properties that relate to the flow behavior of the slurry. Dispersants are used primarily to lower the frictional pressures of cement slurries while they are being pumped into the well.
Converting frictional pressure of a slurry, during pumping, reduces the pumping rate necessary to obtain turbulent flow for specific well conditions, reduces surface pumping pressures and horsepower required to pump the cement into the well, and reduces pressures exerted on weak formations, possibly preventing circulation losses. Another advantage of dispersants is that they provide slurries with high solids-to-water ratios that have good rheological properties. The concept can also be used to design low-density slurries in which the high-solids contents include lightweight extenders.
Dispersants have been extensively studied.
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It is generally agreed that the dispersants minimize or prevent flocculation of cement particles because the dispersant adsorbs onto the hydration cement particle, causing the particle surfaces to be negatively charged and repel each other. Water that otherwise would have been entrained in the flocculated system also becomes available to further lubricate the slurry. Polyunsulfonated Napthalene PNS. The benefit of using PNS is that improved rheological properties can be obtained, and slurries can be pumped with reduced frictional pressures.
PNS can also allow higher solids-to-water ratio slurries to be designed with improved properties. Citric acid is also used as a dispersant in salt- and seawater cement slurries. The concentration of use is limited by the temperature and thickening time desired, although concentrations of 0. FLAs are used to maintain a consistent fluid volume within a cement slurry to ensure that the slurry performance properties remain within an acceptable range. The variability of each of these parameters is dependent upon the water content of the slurry. For example, if the water content is greater than intended, the following will normally occur: thickening time, fluid loss, free fluid, sedimentation, permeability, and porosity will be increased; and density, viscosity, and compressive strength will be decreased.
If the water content is less than intended, the opposite will normally occur. The magnitude of change is directly related to the amount of fluid lost from the slurry. Because predictability of performance is typically the most important parameter in a cementing operation, considerable attention has been paid to mechanical control of slurry density during the mixing of the slurry to assure reproducibility. Of equivalent importance is the slurry density during displacement, which is directly related to fluid-loss control.
Cement slurries are colloidal suspensions consisting of distinct solid and liquid phases. During the cementing operation, there are several opportunities for the fluid phase to separate from the cement slurry. This can occur when the slurry is passing through small orifices or ports, and within the annulus. When the slurry is passing through orifices, the fluid phase can be accelerated, resulting in particle bridging. In a wellbore annulus, fluid can be displaced from the slurry while it is passing though constricted areas, or to the formation, resulting in an increase in the ECD, which can lead to formation fracture lost circulation or flash set dehydration.
After placement, the fluid phase will filter to permeable formations, resulting in a reduction in the slurry volume and effective hydrostatic pressure, creating the potential for the migration of formation fluid into and through the cement column. FLAs are, therefore, used to prevent solids segregation during placement and to control the rate of fluid leakoff in the static state.
This value is excessive for most cementing operations, where permeable formations are encountered or where long columns of cement will be used. The amount of fluid-loss control required for a particular operation varies widely and is largely dependent upon the slurry density, the water content, the formation properties, and annular clearance.
Several materials are effective as FLAs. The materials that are currently in use can be loosely categorized in two groups according to their solubility characteristics: water-insoluble and water-soluble. With the exception of bentonite, the water-insoluble materials are polymer resins. All of the water-insoluble materials function as permeability reducers. The water-soluble materials are modified natural polymers, cellulosics, and vinylinic-based polymers.
The polymeric materials, whether water-insoluble or -soluble, are all synthetic manmade materials. The action of FLAs depends on their solubility. The water-insolubles function by reducing the permeability of the filter cake developed. Bentonite is not typically used as the primary fluid-loss agent in normal-density slurries. Fluid-loss control, obtained through the use of bentonite, is achieved by the reduction of filter-cake permeability by pore-throat bridging. Fluid-loss rates can be erratic because of the concentration of use at a given density, variations in platelet disassociation caused by shear, and stacking arrangement in the filter cake.
Microsilica imparts a degree of fluid-loss control to cement slurries because of its small particle size of less than 5 microns. The small particles reduce the pore-throat volume within the cement matrix through a tighter packing arrangement, resulting in a reduction of filter-cake permeability. PVA is a white to cream-colored powder with a density range of 1. It is a water-soluble polymer derived from polyvinyl acetate and is chemically reactive with acids and alkalis. It is not listed in the water-soluble polymers section because it loses solubility in alkaline environments such as the aqueous phase of a cement slurry.
PVA also provides gas-migration control and enhances cement bonding and acid resistance. Synthetic Latex. This is an oil-in-water emulsion system consisting of a dispersed phase of a water-insoluble elastomer, surfactants, and a water exterior phase. These emulsions are characterized by their milky-white appearance. The most common emulsion used is styrene-butadiene rubber SBR , which provides exceptionally low fluid-loss control, gas-migration control, and acid-solubility resistance. The surfactant system plays a key role in the use of latex in well-cementing applications.
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In cement slurries, the emulsion system readily disperses and exhibits time-, shear-, and temperature-dependent stability. The surfactant system also acts as a dispersant in the cement slurry, resulting in low slurry viscosity. Control of emulsion stability is critical to slurry performance because the rate of inversion of the emulsion controls slurry viscosity and thickening time. Inversion of the emulsion system results in an almost instantaneous conversion to a rubberized mass set that is reported as the pumping time for the slurry.
Two forms of derivatized cellulose have been found useful in well-cementing applications. The usefulness of the two materials depends on their retardational character and thermal stability limits. Hydroxyethyl Cellulose. HEC is typically used at a concentration of 0. Carboxymethyl Hydroxyethyl Cellulose. Since the s, a significant amount of work has been performed concerning synthetic copolymers for use in cement slurries.
Polyvinyl Pyrrolidone PVP. This is a nonionic polymer that is typically used as a fluid-loss enhancer in conjunction with sodium naphthalene sulfonate condensed with formaldehyde SNFC to improve the performance of other polymers. Surfactants are surface-active agents that may be used to modify the interfacial tension between two liquids or between a liquid and a solid. Low-molecular-weight polymers such as SNFC and lignosulfonate are surfactants.
The choice of the proper surfactant can have a significant effect on the FLA itself and its interaction with cement particles. Surfactants can be used to accelerate or retard the solubility or wettability of polymers. Cement slurries can be lost to the formation and not circulated back to the surface during completion of a wellbore. This is defined as lost circulation. It should not be confused with the volume decrease resulting from fluid-loss filtration.
Lost circulation tends to occur in three basic formation types:. In many cases, lost circulation occurs during drilling with loss of drilling fluids, and actions can be taken at that time to combat the lost circulation. At other times, difficulties may be encountered during drilling, indicating potential lost-circulation problems, and measures can be taken to prevent their occurrence during cementing. Typically, there are two steps in combating lost circulation: reducing slurry density and adding a bridging or plugging material.
Additives for prevention of lost circulation can be separated into three basic groups: bridging materials, rapid-setting or thixotropic cements, and lightweight cementing systems. Most bridging materials are considered to be chemically inert with respect to cement hydration. Fibrous materials are, in general, used for controlling lost circulation in highly permeable formations where the fibers form a mat over the surface.
The most common flake material is cellophane. Cellophane flakes act by forming mats or bridges over very narrow fractures. Concentration range of cellophane is usually from 0. Granular materials are most frequently used and include gilsonite, perlite, and coal. These coarse particles are typically used for large fractures and cavernous or vuggy lost-circulation formations. As the cement slurry enters the formation, these large granular particles, in principle, become trapped and block off the opening.
Rapid-setting and thixotropic cements are the preferred means for lost-circulation control in large cavernous or vuggy formations where bridging materials are no longer effective. These cements are usually designed to set up in the lost-circulation zone, ultimately plugging it off. Rapid-setting cements include both quick- and flash-setting formulations. These cements generally give thin slurries but have very rapid setting times. The quick-setting cements will set up while being displaced or shortly after entering the lost-circulation zone, whereas the flash-setting cements form semisolid materials when mixed with water or water-based drilling fluids.
Thixotropic cements have a low viscosity during mixing and placing, but when they enter the formation and are no longer subjected to shear, they gel and become self-supporting. It is often more effective to solve lost circulation by combining the bridging materials with rapid-setting or lightweight systems. The choice of system and the bridging material depends on the type of formation, the size of the lost-circulation zone, the fracture pressure gradient, and the downhole temperatures and pressure, as well as economics. In well-cementing applications, the maintenance of a consistent column of cement is critical to assure proper zonal isolation.
Because of rheological demands and the need for silica or weighting agents in some applications, this is not always possible with conventional materials. It is necessary, therefore, that an additional additive be incorporated into the cement slurry to address the potential problem of particle sedimentation. This group of additives is known as free-water-control additives. Sodium silicate may be used to control free water in normal- and low-density cement slurries. Typically, approximately 0. Biopolymers impart the unique characteristics of thinning at higher shear rates and viscosifying at lower shear rates.
This yields slurries that will more readily go into turbulent or upper laminar flow yet have sufficient low shear to prevent sedimentation. Xanthan gum and Welan gum both provide these characteristics and are typically used at an active concentration of approximately 0. Synthetic Polymers. Synthetic polymers of high molecular weight, which are resistant to alkaline hydrolysis, have been found to be effective as free-fluid-control additives at temperatures where sodium silicate and biopolymers are not effective.
They are typically used at an active concentration of approximately 0. Expansive cements are used primarily for obtaining effective zonal isolation by improving the bond between the cement and the pipe and the cement and the annulus. Good zonal isolation is essential to prevent loss of production, control gas migration, provide protection from corrosive formation waters, reduce water production, and improve confinement of stimulation treatments. The root causes are usually associated with drilling-fluid properties and displacement mechanics, casing expansion and contraction caused by thermal stresses or internal pressures, fluid loss from the cement, and hydration volume reduction during setting of cement.
Expansive cements expand slightly after the cement has set and fill in the void spaces. Because of the restraints imposed by the casing and formation, any additional expansion will occupy the space provided by the internal cement porosity, resulting in a reduction in porosity. The two principal types of expansive additive or cement are post-set crystalline growth or chemical expansion and in-situ gas generation. Crystalline-Growth Additives. The expansion mechanism is the growth of the crystals within the solid cement matrix. These crystals have a greater bulk volume than the original solids from which they form and, as such, cause a wedging action because of the internal pressure of crystalline growth, forcing the solid matrix apart.
Crystal-growth expansion is unilateral in that restraint in one direction does not increase expansion in other directions. The amount of expansion is dependent on a number of factors that include amount of additive, curing time and temperature, and, in some cases, cement-slurry composition. Cement slurries containing high concentrations of salt NaCl, KCl, or CaCl 2 have a long reputation for contributing to expansion.
Salt also contributes to bond improvement by preventing dissolution of the salt formation. In-Situ Gas Generation. Expansion resulting from in-situ gas-generating additives occurs before set while the cement is still in the plastic state. The most common in-situ gas-generating additive is aluminum powder, although zinc, iron, and magnesium are possible alternatives. The expansion is caused by the reaction with alkali and water present in the cement aqueous phase to produce microsized bubbles of H 2 gas.
Expansive forces that are a direct function of the gas generated compensate for any volume losses caused by hydration volume reduction or fluid loss and increase the pressure of the cement against the pipe and formation. Because of the compressibility of the gas, the amount required is more dependent on the hydrostatic pressure of the slurry than on the downhole temperature. Concentrations generally range from 0. Several additives are used that do not fit in any of the preceding categories.
These additives can be used frequently as in antifoam additives or in more-specialized cases, such as mud decontaminants, radioactive tracers, dyes, fibers, and cement for CO 2 resistance. Antifoam additives are frequently used to decrease foaming and minimize air entrainment during mixing.
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Foaming is a secondary effect, often caused by a number of additives. Excessive foaming can result in an underestimation of the density downhole and cavitation in the mixing system. Slurry density is usually measured with a densitometer during mixing to proportion the solids and water to obtain the desired density. When a slurry foams, the entrapped air is also included in the density measurement, and because air compresses under pressure, the actual density downhole becomes greater than that measured on the surface.
Another effect of foaming is that if severe, it can cause cavitation of the pumps and ultimately lead to loss of hydrostatic pressure. The concentration of foaming additive required to be effective is very small, typically less than 0. Antifoam additives consist primarily of polyglycol ethers or silicones or a mixture of both, and may also include additional surfactants. Polypropylene glycol is the most common polyglycol ether used and is favored for its low cost.
It is effective in most situations, although, typically, it has to be added before mixing. In some cases, it can interact with other additives and cause increased foaming. The silicone antifoam additives are a suspension of very fine particles of silica dispersed in a silicone base and can also exist as an oil-in-water emulsion. They can be used both before and during mixing and are highly effective as antifoam additives.
Paraformaldehyde or a blend of Paraformaldehyde and sodium chromate is sometimes used to minimize the cement retarding effects of various drilling-mud chemicals in the event a cement slurry becomes contaminated by intermixing with the drilling fluids. A mud decontaminant consisting of a mixture of paraformaldehyde and sodium chromate neutralizes certain mud-treating chemicals. It is effective against tannins, lignins, starch, cellulose, lignosulfonate, ferrochrome lignosulfonate, chrome lignin, and chrome lignite.
Mud decontaminants are used primarily in openhole plugback jobs and liner jobs and for squeeze cementing and tailing out on primary-casing jobs. Radioactive tracers are added to cement slurries as markers that can be detected by logging devices. They were originally used to determine the location of fill-up or cement top and the location and disposition of squeeze cement, although, now, temperature surveys and cement-bond logs fulfill this function.
Radioactive tracers are still occasionally used in remedial cementing to locate the slurry after placement, if required, and for tracing lost circulation. Radioisotopes are controlled and licensed by the U. Nuclear Regulatory Commission and various state agencies and cannot be used indiscriminately. Small amounts of indicator dye can be used to identify a cement of a specific API classification or an additive blended in a cementing composition. When the dyes are used downhole, however, dilution and mud contamination may dim and cloud the colors, rendering them ineffective.
Conventional Portland cement, mixed at normal density, has low ductility, making it somewhat brittle. This makes it susceptible to post-cementing stresses. Synthetic fibrous materials are frequently added to make the cement more ductile and to reduce the effects of shattering or partial destruction from perforation, drill-collar stress, or other downhole forces.
Fibrous materials transmit localized stresses more evenly throughout the cement and, thus, improve the resistance to impact and shattering. Nylon, with fiber lengths varying up to 1 in. Note: The slurry to be tested should include surface time required if batch mixed and calculated time to bottom.
The methods of testing cement for downhole application are based on performance testing. This type of mortar comprising at least one polyvinyl alcohol PVA is well adapted to the implementation of surface coatings, and gives higher performance in surface hardness properties than mortars of prior art comprising redispersable powders EVA and casein combined with lime, as will become clearer on reading the examples. The term polyvinyl alcohol as used herein is understood to mean the molecular structures represented in diagram form below,.
A most preferred dense mortar comprises 0. Because of the alkaline hydrolysis reactions polyvinyl alcohols can only be used at high concentrations e. Preferred compositions of mortars comprising the combination of a PCP and a resin of the PVA type are given in examples 8, 9, 10 and The ettringite binder according to the invention makes it possible to obtain excellent ettringite formation yields and therefore, a good hardening kinetics without requiring, for the mortar formulation, any complementary source of calcium ions. Another advantage when omitting such a complementary calcium source, which can be either lime, or Portland cement, is that mortar compositions are obtained having more regular performance on the important criteria of the application, Portland cement having in particular a quite variable minor species content, the impact of which on the ettringite formation is decisive.
Thus, preferably, mortars comprising the ettringite binder according to the invention do not comprise either Portland cement or hydraulic lime. It could be obtained under the form of one or more molten or sintered clinkers able to contain crystallized phases or amorphous phases or result from a mixture of various mineral compounds comprising calcium aluminates, obtained in turn through baking or not. The oven to be used can be any oven conventionally used for manufacturing clinkers, such as reverberating furnaces, tunnel furnaces, rotary furnaces or electrical furnaces, either with induction or electric arc.
The calcium sulphate that is appropriate for the binder can originate from anhydrides, gypsum, hemihydrates and mixtures of these, preferably gypsum, hemihydrates and mixtures of these. The purpose of the complementary rheological additives is to improve the starting rheology of the mixed mortar; these can be casein or water-soluble polymers, the function of which is to limit the segregation, such as cellulose ethers, but also welan gums and polysaccharides. These preferably represent 0. The setting regulator additives can be setting accelerators or setting retarders.
Preferably, tartaric acid can be used, in combination with sodium gluconate as a setting retarder. The dry mortar according to the invention makes it possible to obtain a moist mortar by mixing with water. Another object of the invention is the use of an ethylene polyoxide polycarboxylate PCP for the formulation of a mortar according to the invention. Smoothing coatings are produced with mineral compounds of calcium aluminates and calcium sulphates according to the invention. The compositions of the tests 1 to 6 are given in Table 1.
To make the comparison easier, the resin and PCP compositions are given in Table 2, and the performance of mortars of prior art and mortars of the invention are given in Table 3. In Table 1 the total quantity, by weight, of alumina in the binder appears. The concentrations and characteristics of the poly alkylene oxide comb polymers and the structuring polymers are given in the tables of examples that follow.
EV is a resin marketed by Elotex. REZ is a resin marketed by Wacker. The results are summarised in Table 3. The gelation time and the self-spread are measured according to the operating protocol described in the technical guide for the technical notification and the P classification.
Rc 2 h00 represents the measurement made 2 hours after putting the dry mortar with the mixing water; Rc 28 days is the value obtained after 28 days. The adherence when dry is measured with a Sattec dynamometer according to the operating protocol described in the technical guide for the technical notification and the P classification. The measurements after action of water are carried out on models conditioned for 7 days in laboratory atmosphere, immersed for 24 hours in water then reconditioned for 7 days in laboratory atmosphere before measuring.
The tests of resistance to wear by abrasion are carried out using a Taber machine T. Taber Industries, Bryant St. Box , North Tonawanda, N. The grinding wheels used have the following characteristics: Calibrade H diameter 50 mm, band width 13 mm. A weight of g is applied to each of the two grinding wheels added to which is the weight of the support arm, which is g. Thus the total weight on each wheel is equal to g. The sample is made of a disc with a diameter of mm, 10 mm thick, with a hole drilled in the centre to centre it on the test turntable.
The sample is weighed in the test laboratory atmosphere, after being blown with compressed air. The tests are carried out in laboratory atmosphere, i. The grinding wheels are put into contact with the disc, under the pressure of the weights, and the disc undergoes several series of rotations: n revs, then stoppage, dismantling the disc and the grinding wheels, cleaning the grinding wheels and the disc by blowing with compressed air, then weighing the disc. First there are 3 series of 50 revs, followed by a series of revs and a final one of revs. The absolute loss of mass depending on the number of revs makes it possible to evaluate the wear resistance of the material.
For the sake of simplicity in the presentation of results, the loss of mass after revs only is indicated in the examples. It is calculated from the measurement of the depth of penetration into the material of a steel bead of a known diameter under a given load. The bead diameter is 5.
The load is increased progressively and the depth of penetration is measured using a lens fitted with a reticle integrated into the device. The measurement after humidifying the surface is carried out according to the operating protocol described in the technical guide for the technical notification and the P classification. It can be observed that a mortar according to the invention comprising 0.
The mortar according to the invention, also has better performance than a mortar produced with typical ternary ettringite binders containing of a casein based fluidiser and 3. Levelling coats were created the characteristics of which are given in Table 1. The concentrations and types of resins and PCP based fluidisers are given in Table 4. The properties of compositions according to the invention tests 8 to 11 have been compared to a known levelling coat 7. The results are summarised in Table 5. For all the criteria of mechanical properties the performance obtained with PCP levels from 0.
The total porosity and the developed surface of the pores for mortars 3 and 11 according to the invention, and mortar 7 of prior art were compared in Table 6. These values come from measures carried out after 28 days with a Mercure intrusion porosity meter marketed by Micrometrics Instrument Corporation.
It is observed that, the combination of binary ettringite binder with a PCP and low concentrations of structuring polymers, is characterised by better hydration efficiency more hydrates formed leading to a hardened material with lower porosity than mortars produced according to prior art. The surface hardness when dry FIG. It can be seen FIGS. The wear resistance of mortars with test formulations 3 and 8 to 11 was compared to that of known mortars of test formulation 7 FIG.
The more wear resistant the sample tested the lower the loss of mass. It can be seen in FIG. The adherence when dry FIG. Formulas of the invention exhibit values of adherence to the support when dry that are equivalent to that of known mortars despite very low concentrations of structuring polymers, and markedly better performance after the action of water.