Recycling of vulcanized waste rubber through halogenations and amination chemical reactions

摘要

Pollution of the environment with scrap vulcanized rubber causes significant problems, due to the rubber's resistivity to natural conditions. This work deals with the chemical modification of waste vulcanized rubber, especially scrap tires, using chlorination and amination reactions. Chlorination of scrape-powdered tires was carried out in an aqueous and in a non-aqueous medium, passing through a continuous stream of Cl_2 gas. A high yield of chlorinated waste rubber is obtained in the case of the aqueous medium using HOCl and HClO_4 solutions. Amination reactions of the highly chlorinated waste rubber sample were achieved, using different primary, secondary and tertiary amines at 150, 175 and 200°C, for two and three hours respectively. Characterizations of recycled waste rubber are performed using the IR, DSC, and SEM methods. A suggested mechanism of the reactions has been given.