Cellulose ether emulsifier

Auxiliaries. Dispersants ensure that the individual particles in the emulsion paint do not combine to form agglomerates. Protective colloids and emulsifiers are used during emulsion polymerization to ensure that small polymer spheres are formed in the aqueous phase but do not fuse together. They influence film formation of the emulsion paint and can cause foaming. Protective colloids include polyfvinyl alcohols) and cellulose ethers. Emulsifiers include anionic and nonionic surfactants. 

A number of water-soluble cellulose ethers are marketed." Methyl cellulose is prepared by a method similar to that used for ethyl cellulose. A degree of substitution of 1.6-1.8 is usual since the resultant ether is soluble in cold water but not in hot. It is used as a thickening agent and emulsifier in cosmetics, as a paper size, in pharmaceuticals, in ceramics and in leather tanning operations. 

MethoceL [Dow] Cellulose ethers binders, thickeners, film formers, water retention aids, suspending agents, surfactants, lubricants, emulsifier, protective ctdloid for foods, cosmetics, pharmaceuticals, latex paints, construction prods., ceramics, otiier tqrplics. 

Nissan Di anol. [Nippon Oils Fats] Ethoxylated ethers emulsifier and detergoit for animal, cellulosic, and... 

Methyl cellulose n. A cellulose ether in which some of the cellulosic -OH groups have been replaced by -OCH3. The degree of substitution determines properties and uses as thickeners and emulsifiers. Commercially, a granular, white, flakey material, which acts as a water-soluble thickener and stabilizer used in water-based paints. 

Some surfactants (- lignosulfonate) are used to emulsify active ingredients in formulated i. Water-soluble polymers (cellulose ethers, such as - hydroxyethyl cellulose and - carboxymethyl cellulose) promote the adhesion of the active i. on plant leaves and are therefore sometimes added to compounded i. 

For constraction products, cellulose ethers act as thickeners, binders, film formers, and water-retention agents. They also function as suspension aids, surfactants, lubricants, protective colloids, and emulsifiers. In addition, aqueous solutions of certain cellulose ethers thermally gel, a unique property that plays a key role in a variety of applications. 

Methyl cellulose and hydroxyalky methyl cellulose manufacture involves in part Williamson synthesis with methyl chloride and alkoxylation. The various ethers are used primarily in building materials and in industrial applications (O Table 13). Higher grades with greater purities consist of modified vegetable gums, and they find uses in controlled release applications in pharmaceuticals, and in food products and cosmetics where they serve as emulsifiers and texture agents. 

Epichlorohydrin is usually prepared from propene and is mainly used in the manufacture of glycerol and epoxy resins. It is also used in the manufacture of elastomers, glycidyl ethers, cross-linked food starch, surfactants, plasticizers, dyestuffs, pharmaceutical products, oil emulsifiers, lubricants, and adhesives as a solvent for resins, gums, cellulose, esters, paints, and lacquers and as a stabilizer in chlorine-containing substances such as rubber, pesticide formulations, and solvents. 

Methyl and ethyl ethers of cellulose with a degree of substitution (D.S.) of 0.1 to 0.35 are used as emulsifying agents and paper sizes. Hydroxy-ethylcellulose (D.S., 0.5) is also used as a size. Highly substituted ethyl-celluloses (D.S., 2.2 to 2.6) are of great importance in the plastics, film, and lacquer industries. Carboxymethylcellulose (D.S., 0.5 to 0.75) is used as a thickener in foods, and the sodium salt is added to washing powders in which its action in laundering is to prevent redeposition of soil in the fabric. 

Besides vinyl acetate monomer, three other components are neeessary to earry out an emulsion polymerization water, an emulsifier and/or a proteetive eolloid, and a water-soluble initiator. Most commonly, anionic long-chain alkyl sulfonates are used as surfactants in amounts up to 6%. Studies have shown that the rate of polymerization is dependent on the amoimt of emulsifier present, with the rates inereasing as the amoimt of emulsifier is increased up to a certain point and then falling olF as free-radieal ehain transfer to the surfaetant beeomes a serious competing side reaetion [240]. In general, surfactants are used in eombination with a protective colloid. Especially useful as protective colloids are poly(vinyl alcohol), hydroxyethyl cellulose, alkyl vinyl ether-maleic anhydride and styrene-allyl alcohol copolymers, and gum arable. Water-soluble initiators, particularly potassium persulfate, alkali peroxydisulfates, hydrogen peroxide, and various redox systems, are most commonly used. 

Emulsifiers such as methyl cellulose, polyethylene glycol monstearate, polyethylene glycol trimethyl nonyl ether added to prepare stable O/W emulsions of the antifoam if desired... 

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