Preparation of polyoxymethylene/methyl vinyl silicone rubber/thermoplastic polyurethane ternary thermoplastic vulcanizates with good toughness properties

Abstract

Novel thermoplastic vulcanizates (TPVs) based on polyoxymethylene (POM) and methyl vinyl silicone rubber (MVQ) have been prepared by dynamic vulcanization process through a batch mixer. During the preparation of TPV blends, Di-(tert butyl peroxyisopropyl) benzene (BIBP) was used as the curing agent in order to make MVQ cross-linked and Thermoplastic polyurethane elastomer (TPU) was used to coat MVQ for improving the compatibility of MVQ and POM. In order to understand the influence of different compositions on TPV blends, five groups of experimental processes were described in detail. During these experiments, the amount of POM was reduced from 70 phr to 30 phr, that of MVQ was gradually increased from 18 phr to 42 phr, and TPU was increased from 12 phr to 28 phr. In addition, the morphology and properties of TPVs were studied by differential scanning calorimetry, Fourier transform infrared, SEM, dynamic mechanical analysis, and mechanical tests. The mechanical testing results showed that with the decrease in amount of POM and increase in the total amount of MVQ and TPU, the tensile strength of the TPV blends gradually was decreased, and the elongation at break was increased accordingly from 35.2 ± 6% of pure POM to 142.8 ± 11% of sample 5#.