Optimization of the modification technologies of asphalt by using waste EVA from packaging

Packaging wastes not only pollute the environment, but also waste resources. In this study, bags of suits made mainly from ethylene(vinyl acetate) copolymer (EVA), as the modifier, were used to improve the properties of raw asphalt. On the basis of the common physical modification, crosslinking agents and catalysts were added to the raw oil asphalt. The modification technologies were studied carefully. The results showed that crosslinking agents and catalysts could make the polymer react with raw asphalt, thus providing chemical connections between them and forming three-dimensional network structures. As a result, the asphalt performance was improved. In addition, the dosages of the crosslinking agent, modification temperature, and time also had effects on the performance of the modified asphalt. When the ratio of divinylbenzene to asphalt was 0.0125, the ratio of catalyst to asphalt was 0.025, the temperature was 140°C, and the modification time was 2.5 h, the softening point of the asphalt rose from 49.5°C to 63.5°C, and the penetration degree dropped from 68.5 to 39.1 (0.1 mm). The results showed that after the modification with waste EVA, the performance of the asphalt had been significantly improved and stabilized. J. VINYL ADDIT. TECHNOL., 2009. © 2009 Society of Plastics Engineers