Structure Development in Melt Spinning Polypropylene-EPM Blends and Dynamically Vulcanized Polyolefin TPEs

Abstract

Abstract Polypropylene blends, both mechanical blends and a dynamically vulcanized blend, have been melt spun into fibers. Melt spinning was carried out through air and in ice water. Melt spun filaments were characterized by wide angle x-ray diffraction (WAXS), birefringence and differential scanning calorimetry (DSC) measurements. Generally, the polypropylene crystalline orientation-spinline stress relationship is the same for the homoploymer, the blends and the dynamic vulcanizate. However, the blends and the dynamic vulcanizate have much lower birefringence apparently due to a lack of orientation in the rubber phase. It was shown that the PP contribution to the birefringence for all the systems is the same at the same spinline stress.