Effects of coupling agents on the mechanical and rheologica properties and mica‐reinforced polypropylene

Dimethylaminoethyl methacrylate (DMAEMA) was investigated as a prospective coupling agent for mica‐reinforced polypropylene. Composites prepared with the widely‐used silane coupling agent, N‐(4‐vinylphenyl) methyl‐N′‐(3‐trimethoxysilylpropyl)ethylenediamine monohydroehloride (Z‐6032), were compared with the amino‐coupled composite. Improvements in the flexural properties at room temperature were observed with the two coupling agents: a 22 percent increase in the strength with the silane compared to a. 16 percent increase with DMAEMA. Cone‐and‐plate viscometry at 220°C showed that the addition of coupling agents greatly, reduces the viscosity of the composite: a 50 percent decease was obtained with the silane‐treated composite and a 20 percent decrease with DMAEMA.