Stabilization of Waste Plastics with Lightly Pyrolyzed Crumb Rubber in Asphalt: Fid-Bau Portal

Stabilization of Waste Plastics with Lightly Pyrolyzed Crumb Rubber in Asphalt

Ma, Yuetan / Zhou, Hongyu / Polaczyk, Pawel / Huang, Baoshan

Modifying asphalt is a potential high‐value application for reusing waste plastics because of high volume usage asphalt in highway construction. However, simply blending hot plastics and asphalt encounters difficulties related to the poor solubility of polymers, which limits the formation of a swollen network with asphalt molecules. The polymer phases also tend to coalesce and separate from asphalt during high‐temperature storage in static conditions. The present study developed a process to stabilize waste plastics in asphalt and improve binder storage stability utilizing lightly pyrolyzed crumb rubber (LPCR). The untreated crumb rubber and LPCR were collected to blend with waste plastics for asphalt modification. The storage stability and rheological properties of modified binder blends were evaluated through cigar tube test and dynamic shear rheometer (DSR) test. Polymer phases and network structures were characterized through optical microscopy. Fourier transform infrared spectroscopy (FTIR) was utilized to investigate the reaction mechanisms of LPCR and its interaction with the asphalt binder system. It was found that the pyrolyzed process improved the rubber solubility and storage stability of modified binder blends. The co‐existence of rigid plastic and soft rubbery regimes in an entangled network provided a promising pathway to improve the mechanical performance of asphalt binder in both high‐ and low‐temperature domains.