Novolac/乙烯-醋酸乙烯酯共聚物共混体系中的反应诱导Spinodal相分离

REACTION INDUCED SPINODAL DECOMPOSITION IN THE BLENDS OF NOVOLAC/EVA

Ｎｏｖｏｌａｃ／乙烯醋酸乙烯酯共聚物共混体系中的反应诱导Ｓｐｉｎｏｄａｌ相分离陈文杰吴坚江明（复旦大学高分子科学系和国家教委聚合物分子工程实验室上海２００４３３）关键词Ｓｐｉｎｏｄａｌ相分离，共混物，光散射，酚醛树脂，固化反应在高分子多相体系中，...

Phase separation during curing reaction in a ternary mixture of Novolac, Poly(ethylene co vinyl acetate) (EVA) and Hexamethylenetetramine (Hexa,curing agent) was investigated by time resolved light scattering.Novolac/EVA system exhibited a Low critical Solution Temperature (LCST) type phase behavior due to H bonding interaction between components.In the early stage of curing,the mixture was in single phase.As the curing reaction proceeded,phase separation took place via spinodal decomposition (SD) induced by the increase in the molecular weight of Novolac.The time variation of q m , the characteristic wavenumber of phase separated structure at which the maximum intensity is located,is quite different from iso quench thermally induced SD. q m is increased slightly with time attributed to the rapid curing reaction and eventually levelled off with gelling.Cocontinuous phase separated structure was ultimately formed during curing reaction.