Effect of different waste plastic modifiers on conventional asphalt performance: optimal preparation parameters determination and mechanism analysis.

The typical treatment of waste plastics has become a global environmental problem. In light of recent developments, waste plastics used as asphalt modifiers offer an efficient approach to solve this problem. This paper studied the effects of three kinds of waste plastic-modified asphalts (WPMA), with polypropylene (PP), polyethylene (PE) and ethylene-vinyl acetate copolymer (EVA) as their respective modifiers, on the conventional asphalt performance. Furthermore, an orthogonal experimental design (OED) was used to determine the preparation parameters of WPMA. Thereafter, thermogravimetric-differential scanning calorimetry (TG-DSC) and Fourier transform infrared spectroscopy (FTIR) were employed to expound the mechanism of WPMA. It was then subsequently ascertained that the optimum preparation parameters of PP-modified asphalt (PPMA) and PE-modified asphalt (PEMA) were 170 °C, 3000 rpm, and 30 min, while the optimum preparation parameters of EVA-modified asphalt (EVAMA) were 180 °C, 3000 rpm, and 30 min. In addition, WPMA displayed better high-temperature performance and are inherently more suitable for pavement in high-temperature regions. Ultimately, this study will effectively solve the disposal of waste plastic and promote the research and application of WPMA in the future.

Analysis of the Influence of Production Method, Plastic Content on the Basic Performance of Waste Plastic Modified Asphalt.

The sustainable reuse of waste plastic as an alternative construction material has numerous environmental and economic advantages. New opportunities to recycle waste plastic in asphalt for road construction would mitigate landfill issues and significantly reduce global carbon emissions. With a clear aim to contribute to a more efficient reuse of waste plastic, this paper reutilized two types of waste plastic (polypropylene (PP) and polyethylene (PE)) as asphalt modifiers to improve the performance of asphalt pavement as well as to achieve the purpose of sustainable recycling waste plastic. Therefore, the optimal preparation parameters of plastic-modified asphalt were recommended by the orthogonal test. Then, the dispersion and modification mechanisms of plastic particles in plastic-modified asphalt were further studied by Fourier Transform Infrared Spectroscopy (FTIR) and Thermogravimetric Differential Scanning Calorimetry (TG-DSC). The results show that the asphalt containing PP and PE shows better overall performance at high temperatures compared with the base asphalt. Furthermore, PE-modified asphalt and PP-modified asphalt exhibited optimal properties when prepared at 3000 rpm for 30 min at 170 °C. Moreover, the results of the expansion mechanism show that the main reaction process of plastic asphalt is a physical change. Finally, PP-modified asphalt and PE-modified asphalt generally perform well and are suitable for high-temperature areas. Consequentially, the results of this research promote the recycling of waste plastic, ultimately advocating the recycling of waste materials and environmental protection of pavement construction.

Compound reutilization of waste cooking oil and waste engine oil as asphalt rejuvenator: performance evaluation and application.

The comprehensive utilization of waste cooking oil (WCO) and waste engine oil (WEO) is of great significance to build a sustainable society because recycling WCO and WEO to develop a rejuvenator for asphalt pavement not only aids the reduction of environmental pollution, but also brings about significant benefits to the Earth's sustainable development. With a clear aim to contribute to a more efficient reuse of the waste oils and recycled asphalt mixtures, this paper develops a high-efficiency compound rejuvenator and determines the optimal combination of its main constituents (WCO and WEO) through orthogonal tests. Furthermore, the performance of the rejuvenator is verified by means of the four-fraction test and the traditional asphalt performance tests (penetration, ductility, softening point). These tests confirm the regeneration efficiency of the compound rejuvenator, and the optimum dosage of the compound rejuvenator is found of 7%. Subsequently, the mechanism of the compound rejuvenator in aged asphalt is examined, and following the application of the compound rejuvenator, it was concluded that the reclaimed asphalt pavement (RAP) could be maximized by 45%. Consequentially, the results of this research promote the recycling of WEO, WCO, and waste asphalt pavement materials, ultimately advocating the sustainability of pavement construction.