Thermoplastic vulcanizates based on compatibilized polyurethane and silicone rubber blend

摘要

The polyurethane (PU)/silicone rubber dynamic vulcanizated elastomer was prepared using Pt catalyst and organohydrido silicone compound as cross-linking agent. The effect of segmented PU modified by hydroxyalkyl functional polydimethylsiloxane (Si-PU) as a compatibilizer was investigated. It is found that simple blend shows co-continuous structure and worse mechanical properties. After dynamic vulcanization, the elongation at break improved to 745.8% when the contents of catalyst and cross-linking agent are 0.12 phr and 1.65 phr, respectively. The introduction of Si-PU in 4.5 phr further improves the value to 942.6% and the sizes of cross-linked rubber dispersed in the continuous PU matrix are less than 8 urn. Si-PU copolymer shows better compatibilization effect.