Neutral polymers, solubilization

Preteatment with pectinases improves meehanieal debarking of wood significantly. In addition to polygalacturonase, enzymes hydrolysing the neutral polymers in cambial tissue (arabinanase, galactanase, and glucanase) are needed for effective solubilization of spruce cambium. 

Dawson, D.M., Melton, L.D., and Watkins, C.B. 1992. Cell wall changes in nectarines (Primus persica) Solubilization and depolymerization of pectic and neutral polymers during ripening and in mealy fruit. Plant Physiol. 100 1203-1210. 

Hydrogenation of polymers results in better thermal and oxidative stability, and several attempts were made to employ homogeneous catalysis for this purpose. An ABS copolymer was reduced in the form of an aqueous emulsion with neutral and cationic Rh(I) complexes. The slightly water-soluble cationic complex was more efficiently built into the micelles of the anionic detergents used for polymer solubilization and this resulted in better conversions, e.g., 70% in contrast to 20% with [RhCl(PPh3)3] [76],... 

Uses Humectant, solubilizer, lubricant, fixing agent, vise, control agent for cosmetics and toiletries Features Neutral polymer... 

Resin Solubilizers. In general, water-soluble resins ate amine salts of acidic polymers. Water-soluble coatings formulated with AMP-95 and DMAMP-80 exhibit superior performance (15,16) (see Water-SOLUBLE polymers). AMP-95, used in conjunction with associative thickeners (17) or hydroxy-ethylceUulose, provides for the most efficient utilization of such thickeners. It also is the neutralizer of choice for use with hair spray resins. 

The opposite effect on quenching by neutral molecules when small amounts of detergent are added to aqueous solutions of 3 could be attributed to several possible factors. First, the addition of detergent to the polymer may help in affording a more hydrophobic environment in its vicinity that may enhance the polymer-small molecule association. Also, since surfactants such as DTAB are well known to solubilize organic molecules in water, it appears reasonable that clusters of the detergent may combine with the neutral quenchers and function as chaperones to increase their effective solubility and thus enhance the complex formation with the polymer. 

The water-solubilfeed polymers lie between tiie latexes and polymer solutions i. e., between tiie colloidal and molecular sizes. These water-solubilized polymers are often prepared by the neutralization of carboxyl-containing latex particles with base, to give swelling and partial disintegration of the particles. 

Enteric polymers can be coated from aqueous latexes or from aqueous solutions that are produced by solubilizing the polymer via pH neutralization with the addition of an alkali or organic base. Typical neutralizing agents used to create aqueous solutions of enteric polymers include ammonia sodium hydroxide, triethanolamine 2-amino-2-methyl-1-propanol and ammonium hydrogen carbonate. In most cases acid preireal-ment is required to convert the enteric polymer from its salt state back to the neural state to achieve enteric functionality of the polymer however, it has been reported that acid... 

A review (13) of water-based inks points out that ink vehicles must have "tack" for printability and that high solution viscosities are requited to give this tack. The viscosity of most latexes is too low to give this tack, so water-soluble or water-solubilized polymers are usually used. Upon drying, however, these polymers must no longer be soluble in water. Therefore, most water-based ink vehicles are ammonium hydroxide-neutralized alkaline solutions of carboxyl-containing polymers when the solution is dried, the ammonia evaporates, leaving the polymer in its water-insoluble carboxyl form. 

When the polymer acids are treated with metallic bases the bulk and solution properties of the neutralized products are changed markedly. In bulk the neutralized products behave as if they are covalently cross-linked. In fact, they are not covalently cross-linked since they are soluble in mixtures of hydrocarbon and polar solvents (12). Nevertheless, their solution behaviors are so significantly different from those of the base polymers and the polymeric sulfonic acids that effective neutralization is not a simple operation. If solutions containing the free polymeric sulfonic acid are treated with an aqueous solution of neutralizing agent, a gel results which prevents effective neutralization and processing. The metal sulfonates are solubilized through the inclusion of a polar cosolvent such... 

Solubilizable Dispersions (19). The chemistry of solubilizable acrylic dispersions is a hybrid of emulsion and water-reducible technology. These polymers are synthesized by emulsion techniques but contain acidic or basic functionality that renders them water soluble upon neutralization with an appropriate titrant. For example, if the solubilizing functionality is acidic, the polymer will behave like an emulsion below a certain critical pH range, like a highly swollen emulsion within the critical pH range, and like a true water-soluble polymer at sufficiently high pH values. Such polymers offer a favorable balance of properties for many coating applications. 

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