A novel thermoplastic elastomer by reaction-induced phase decomposition from a miscible polymer blend

A miscible polymer/polymer system, poly(vinylidene fluoride) (PVDF)/acrylic rubber (ACM), was subjected to dynamic vulcanization to yield an oil- and heat-resistant thermoplastic elastomer (TPE). The morphology of the TPE has been investigated by small-angle X-ray scattering (SAXS), dynamic mechanical analysis (DMA), and transmission electron microscopy (TEM). It was shown that phase decomposition occurs during the dynamic vulcanization process and that the TPE consists of a PVDF-rich matrix and ACM-rich crosslinked particles of submicron diameter in which PVDF crystal lamellae are well developed. The TPE displayed excellent mechanical properties, namely, high tensile strength, large elongation at break, and excellent strain recovery from the highly deformed state. It also showed excellent oil and heat resistance. The formation of PVDF lamellae in ACM-rich particles may be the reason for the excellent oil resistance.