Pyridinium High Polymers—A New Class of Oil-Resistant Synthetic Rubbers

Abstract

Copolymers of butadiene and 2-methyl-5-vinylpyridine are readily vulcanized by heating in the presence of organic halides. The number of effective crosslinks can be readily calculated from moduli of swollen stocks using the statistical theory of rubber elasticity. Crosslinking depends upon the amount and activity of the quaternizing agent. However, even at low levels of halide concentration, it appears that several quaternary groupings are necessary for each effective crosslink. Zinc oxide greatly increases the moduli of the swollen copolymer-halide systems. However, sulfur and accelerator alone have little effect on the same system and these agents do not further increase the moduli of the swollen ternary system, copoylmer-halide-zinc oxide.