Devulcanization of Ground Tire Rubber Powder by Reactive Mixing Process; Effect of Modifier

Scrap tires, as the post-consumer waste, have been subjected to incineration or landfill. However, these methods result in severe environmental problems such as air pollution. Recycling of waste rubber is becoming a more serious issue that the rubber industry faces in recent years due to crosslinked molecular structures of the vulcanized rubber which prevents further processing. Devulcanization of waste rubber and reuse it like the virgin rubber or serve as a substitute for virgin rubber is considered as an optimum method to resolve the problem. In this work, high shear stress and high temperature in the presence and absence of the residue substance of crude oil refineries as the modifier was employed to devulcanize rubber powder. Devulcanization process was carried out in an internal mixer at temperature of 2000C and rotor speed 90 rpm and in presence of different amount (0, 10, 20, 30, 40 and 50%) of modifier. Performing Fourier Transform Infrared (FTIR) test on the mixed product revealed devulcanization of the rubber. The yield of devulcanization was investigated by measuring crosslink density of the product through using swelling test and Florry Rheiner equation. The obtained results showed that increase in the amount of the used modifier resulted in higher reduction of crosslink density

کلیدواژه ها:

Rubber Powder ، Modifier ، Internal Mixer ، Devulcanization