LAUSR

A mechano-chemical modification process for waste rubber powder (WRP) was investigated in this paper. 2-Mercatobenzothiozole (accelerator M) was introduced as a peptizer to improve plasticity of WRP, and 3-aminopropyltriethoxysilane (silane coupling agent KH550) was used as a surfactant to further modify the surface of plasticized rubber powder (PRP) to improve interfacial bonding with epoxidized natural rubber (ENR). Infrared spectrums showed that the WRP generated more oxygen-containing groups by mechanical forces in the presence of accelerator M and then grafted amino groups with KH550. The mechano-chemical process with accelerator M changed the structure of WRP obviously shown by sol fraction and microstructure of PRP, which increased the mechanical properties and crosslink density of full rubber powder vulcanizates. After further modified by KH550, the modified rubber powder (MRP) had a positive chemical interfacial bonding with ENR, changing the fracture surface and improving the mechanical properties of vulcanizates. The cure characteristics of the vulcanizates also illustrated that accelerator M and KH550 participated in the vulcanization process increasing the curing efficiency. The best mechanical properties of ENR/MRP vulcanizates were better than the neat ENR vulcanizates. It indicated that the mechano-chemical process with accelerator M and KH550 will be a potential method to reclaim WRP.