Effects of plasticizing time on flexural fatigue of soft Poly(vinyl chloride)

In this study, seven gradient plasticizing time at 200°C were set to explore the effects on Bally Flex fatigue of soft poly(vinyl chloride) (PVC). The results showed that the rotational rheometer was well used to characterize the plasticizing process of PVC paste. The optimum plasticizing temperature of soft PVC was about 180°C. Within a certain range of plasticizing time, the glass transition temperature of soft PVC decreased with the extension of plasticizing time, and the Bally Flex fatigue life was prolonged as the plasticizing time extended. When the plasticizing time was 105 s, the plasticization was nearly completed, which can be used as an optimum plasticizing time in terms of manufacturing efficiency and quality. When the plasticization time was 135 s, the degree of plasticization was the highest. The fatigue cycles of Bally Flex and breaking energy (W) at −20°C were 136,000 and 4850 J·m−3, respectively. It was concluded that Bally Flex fatigue life and W had a good positive correlation. Thus, the tensile test can be used as a simple approach to predict the Bally Flex fatigue life trend of soft PVC specimens.