Elastomers optimum dispersion

The compounding technique for latex differs from that of dry mbber and is fundamentally simpler. A critical factor of colloidal stabiUty makes necessary that each ingredient is of optimum particle size, pH, and concentration when added as an aqueous dispersion to the latex. Rubber latex is a colloidal aqueous emulsion of an elastomer and natural mbber latex is the milky exudation of certain trees and plants that of greatest commercial importance is the... 

Compatibilization along with dynamic vulcanization techniques have been used in thermoplastic elastomer blends of poly(butylene terephthalate) and ethylene propylene diene rubber by Moffett and Dekkers [28]. In situ formation of graft copolymer can be obtained by the use of suitably functionalized rubbers. By the usage of conventional vulcanizing agents for EPDM, the dynamic vulcanization of the blend can be achieved. The optimum effect of compatibilization along with dynamic vulcanization can be obtained only when the compatibilization is done before the rubber phase is dispersed. 

In many cases, toughening of a brittle polymer can be achieved by introduction of stiffness heterogeneity, viz. incorporation of an elastomer, immiscible polymer, sohd particles, gas bubbles (i.e., foaming or micro-foaming), etc. However, the size and concentration of these heterogeneities should be optimized. For most thermoplastic s the optimum diameter of the dispersed elastomeric particle is d < 3 jj.m and its volume fraction ... 

The surface of the filler must be compatible with the molten polymer or, if a thermoset system, with the uncured system, (i.e., the resin or elastomer), to achieve the optimum rheology and filler dispersion. 

In tire manufacture a certain amount of aggregation produces optimum toughness. A major problem is keeping the carbon black properly dispersed among the several elastomers generally blended for the purpose. 

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