Effects of Multiple Recycling on the Structure and Morphology of SEBS/PP Composites

[摘要] A study of the chemical, mechanical, rheological, and morphological properties of recycled styrene–ethylene–butylene–styrene/polypropylene (SEBS/PP) composites was performed to investigate the viability of the application of these materials as recyclable halogen‐free alternatives to plasticized poly(vinyl chloride). The SEBS and PP were initially compounded in a ratio of 37 and repeatedly recycled. After over ten rounds of recycling, the SEBS/PP composites exhibited no significant changes either in tensile strength or in tensile elongation. However, a reduction in hardness, decrease in the temperature of the onset of thermal decomposition, and significant increase in their melt flow index (MFI) values were observed. Notably, X‐ray scattering measurement and transmission electron microscopy experiments of the SEBS/PP composites indicated that these changes in hardness and MFI originated from morphological changes of the SEBS/PP composites resulting from thermal degradation of the SEBS triblock copolymers that occurred over multiple rounds of recycling.

[学科分类] 化学（综合）

[关键词] Styrene–ethylene–butylene–styrene/polypropylene composites;Recycling;Morphological properties;Melt flow index