Reconsideration of the effects of a coupling agent in talcum‐filled plastics

Structure and morphology of talcum-filled polyethylene (HDPE–talc) were studied to examine the nature of beneficial effects of commercial silane coupling agents. Effects of the additive on the structures of the blends with various talc contents were studied through differential scanning calorimetry (DSC) analyses. Mechanism of reinforcement by the flake-like filler were analyzed through both classical treatments and a percolation model. Results suggest that for the studied system, silane had changed properties of the filled plastics, mainly through enhancement in filler dispersion and modification of matrix morphology. Choice of silane as coupling agents was thus questioned for the filled polyolefins with relatively low cost-to-performance ratio. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 67:1227–1236, 1998