Effect of block copolymer coupling agents on properties of mica reinforced polymeric composites

In the systems of mica reinforced polymers based on polystyrene and polypropylene, block copolymers polystyrene-b–polyisoprene-b–polyvinyltriethoxysilane (PS-b–PI-b–PVTOSI) and polystyrene– polyvinyltriethoxysilane (PS-b-PVTOSI) were used as macromolecular coupling agents to treat mica. Compared to common coupling agents, e.g. A-174, A-151 and A-1100, such block copolymer coupling agents can much more effectively improve the interfacial adhesion of mica reinforced polystyrene and significantly increase the mechanical properties of the composites. In a certain range, an appropriate increase in the block lengths of polystyrene and polyvinyltriethoxysilane is desirable for the mechanical properties. The introduction of the middle flexible polyisoprene block and the increase in its length are of advantage to the impact strength of the composites. The good compatibility of the matrix polymer and the block copolymer coupling agent is in favor of the improvement in the interfacial adhesion.