INFLUENCE OF CROSS-LINK STRUCTURE ON IMPA CT STRENGTH OF ABS

Viscoelastic behavior and impact strength were examined for model ABS resins for various gel contents in dispersed polybutadiene particles a nd also grafting degree. ABS resins with the gel content of 50% and 70 % showed an impact strength which increased with the grafting degree. However, ABS resins with the gel content of 80% had a low value indepe ndent of the grafting degree. Electron microscopic observation and H-1 spin-spin relaxation measurements suggested that a crosslinking react ion was induced in the polybutadiene particle with the gel content of 80% by radicals due to an initiator for the graft reaction. GPC experi ments also suggested that the polybutadiene particle with the gel cont ent of 80% had more branches than other polybutadine particles had. Th us, the crosslinking and the degree of branching influenced the viscoe lastic behavior and impact strength effectively.