Assessment of Plastic Waste Modification to Asphalt Materials Using the Wet Process

In 2017, China passed the National Sword Policy that established a policy to no longer import plastic waste from other countries. Before 2017, China imported approximately 45% of the world’s waste plastic. The had a significant impact on how the U.S.A. and other countries around the world handled the tremendous surplus of plastic waste. Research studies as late as the 1970s demonstrated that plastic may be utilized as an asphalt modifier when properly dosed and controlled, although limited recent data exists utilizing the mixture design and testing procedures of today. A research study was conducted to evaluate three different processed waste plastic materials using a wet process. The wet process is defined as the waste plastic being added and blended with the asphalt binder before addition to the asphalt mixture. The different processed waste plastics were blended at three different dosage rates with conventional and research grade asphalt binder characterization conducted. The asphalt binder testing was used to identify the best waste plastic material and dosage rate that was used in an asphalt mixture design subjected to various asphalt mixture performance tests. The results of the study that the indicated plastic type and dosage rate had a significant impact on performance. Overall, the study showed that certain plastic types will be detrimental to asphalt binder and mixture performance, while others may be used to provide performance improvements.