Development of novel applications of crosslinked elastomer scrap.

摘要

This study focuses on the environmental effect of scrap rubbers, originated from scrap tires, shoe soles and roofing material, to the ground water and the air. It was concluded that although a wide application of scrap rubber in the civil engineering field is feasible, caution and complementary regulation are urgently needed.; A more important and practical alternative, the employment of scrap rubber in thermoplastic elastomers, a family of new materials, was initiated and studied systematically. It was found that the melt flow index (MFI) of the thermoplastic material is very critical for the scrap rubber/thermoplastics blending and that, among others, the size of rubber particle and the residence time also play important roles.; Furthermore, chemical modification was studied in order to promote a good compatibilization between the scrap rubber and the thermoplastic material. It is concluded that a radical initiated process can greatly improve the mechanical properties of the resulting blend, specifically EPDM/PP blends. Lewis acids, chemicals to promote the Friedal-Crafts reaction between the rubber particle and the plastics, and phenolic resin were employed with appreciable improvement in the mechanical properties in SBR/PP blends.; A study of the controlling factors in the scaling-up for the scrap rubber/PP blending was performed. It is concluded that the mechanical properties of extruded composites from the twin-screw extruder can be predicted based on the studies performed in the batch mixer, provided that the residence times in both processes are comparable.