Microstructure and properties of bromo-isobutylene–isoprene rubber/polyamide 12 thermoplastic vulcanizate toward recyclable inner liners for green tires

Abstract

We successfully prepared bromo-isobutylene–isoprene rubber (BIIR)/polyamide 12 (PA 12) thermoplastic vulcanizate (TPV) by dynamic vulcanization (DV), and studied the microstructure and properties of BIIR/PA 12 TPV toward recyclable inner liners for green tires, to reduce fuel consumption and carbon emissions. The as-prepared BIIR/PA 12 TPV exhibits good mechanical properties, good elasticity, easy processability and good gas barrier properties. More importantly, our BIIR/PA 12 TPV still exhibits good properties after recycling several times. The mechanism for the formation of the phase morphology and morphological evolution during dynamic vulcanization, and the microstructure–property relationship of BIIR/PA 12 TPV were thoroughly studied to provide guidance for the preparation of high-performance BIIR/PA 12 TPVs toward tire inner liners. As the DV proceeded, the size of the dispersed BIIR particles and the thickness of the PA 12 ligaments decreased, leading to the strengthening of the rubber network. Although the rheological properties slightly deteriorated, the elasticity, the mechanical properties and the gas barrier properties of the TPVs were obviously improved as the DV proceeded.