Studies on thermal and combustion properties of thermoplastic vulcanizates composites modified by polyhedral oligomeric silsesquioxane

PP/EPDM (TPV) is a common thermoplastic elastomer with excellent performance and a wide range of uses. Polyhedral oligomeric silsesquioxane (POSS) with its own functional organic group (OV-POSS) was used to improve the combustion performance of TPV systems. 1 wt%, 3 wt% and 5wt% OV-POSS were added to TPV respectively, and their mechanical properties and thermal stability were tested. The results showed that the TPV mechanics performance of OV-POSS was slightly reduced, but the thermal stability was improved. Cone test results showed a 53% reduction in the heat release rate of TPV containing 5wt% OV-POSS compared with TPV without adding OV-POSS. The release of CO and CO2 also decreased significantly, and the amount of carbon formation increased from 1.1% to 14.8%. As can be seen from TG-IR analysis, the addition of OV-POSS slows down the thermal decomposition process of hydrocarbons. OV-POSS was added to improve flame-retardant properties and reduces fire risk of TPV.