Binders specialty

High purity CA cements are primarily used as binders for high strength refractory castables to form linings up to about 1.0 m thick, as, for example, in iron blast furnaces. Since the 1970s, large monolithic precast CAC castable shapes have found increased usage in a variety of specialty fired shapes that are too expensive to be inventoried. 

Specialty binders may be used in novel or unique forming operations. Cross-linking polymers are used to induce gelation in gelcasting. 

Another factor is the need for thinner viscosity binders. This puts a heavy demand on the water holding property of the starch. A retrograded starch will result from a non-derivative made to a low viscosity. Specialty starches are providing the properties needed... 

Many coatings will use latex as a binder either singly or in combination with starch. Addition of specialty starch allows cost control and depending on the quality demanded, the level of starch can be varied. Many formulas will use 16 to 18 parts of binder based on the clay and frequently ratios of 5 starch and 12 latex are used. 

However, some excipients have multiple functions. For example, microcrystalline cellulose can function as a filler, a binder, and a disintegrant. As seen in Table 7.3, a typical low-dose formulation could include more than 85% filler—binders. Thus, physical and chemical properties for these specialty excipients are extremely important in a low-dose formulation for manufacturability, product performance, and longterm stability. Because the poor physicomechanical properties of components are not altered during manufacture as they are in the wet or dry granulation process, critical material properties and their impact on product quality attributes should be well characterized and understood.23 Discussion in this section will focus on fillers-binders. For those requiring more information on excipients, several excellent books and review articles are available in the literature.24-27... 

The major starch sources are corn, potato, waxy maize, wheat and tapioca. Refined starches are supplied in powder form or as slightly aggregated pearl starch.16 Unmodified (native) starch is rarely used in the paper industry, except as a binder for laminates and in the corrugating process. Most starches for use in papermaking are specialty products that have been modified by controlled hydrolysis, oxidation or derivatization.17... 

Anionic starches are obtained by reaction with phosphoric acid and alkali metal phosphates or by derivatization with carboxymethyl groups.30,31 This modification is primarily used to introduce amphoteric properties into cationic com starch for application on the wet end of the paper machine. Anionic starches with carboxymethyl substitution are used as thickeners in coating colors or as binders in coatings for specialty paper grades. Oxidized starches are inherently anionic but without thickening action. Potato starch already carries sufficient natural anionic charge to provide amphoteric properties after cationization.32... 

Pregelatinized starch is sometimes used as a coating binder,258 but these products are difficult to wet out uniformly and may cause problems due to clumping. Small granules of starch are used in specialty coatings.259... 

E-mail Address karine.boutouta specialchem.com Web Address www.specialchem.com SpecialChem S.A. provides information and services for the specialty coatings industry including plastics, bonding, adhesives, inks, cosmetics and sealants. The website offers industry news, technical articles, a glossary and a database of additives and resins/binders. SpecialChem also offers free technical assistance and web seminars. 

International Specialty Products. Technical literature Flasdone S0630 A binder for direct compression and wet dry granulation 2002. 

Immobile liquids—addition of specialty binders that sorb the granulating solvent, soften, deform, and adhere to particles, then harden during drying. 

Use (Solid) Mechanical rubber products, lining oilloading hose and reaction equipment, adhesive cement, binder for rocket fuels, coatings for electric wiring, gaskets and seals. (Liquid) Specialty items made by dipping or electrophoresis from the latex. (Foam) Adhesive tape to replace metal fasteners for automotive accessories, seat cushions, carpet backing, sealant. 

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