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Waste plastics and rubber have always posed a threat to the environment and a great challenge for disposal. The use of these two waste materials as modifiers for road asphalt provides new road asphalt binders and at the same time provides a new way for waste material resource treatment. Rubber-modified asphalt and plastic-modified asphalt have received widespread attention due to their green and low-carbon characteristics and some performance advantages, but there are still some performance shortcomings that hinder their promotion and application. In order to continue to explore the application of waste materials in the field of road engineering, combined with the performance advantages of both, many scholars began to study the rubber-plastic composite modified asphalt (RPCMA). Therefore, this paper reviewed the different types of waste rubber and plastic, the comprehensive performance of different types of asphalt and its mixture performance, analyzed the modification mechanism of rubber-plastic composite modified asphalt and its performance changes. The results show that rubber-plastic composite modified asphalt is mostly prepared by directly adding modified materials. However, the pretreatment or melt granulation of rubber and plastic will make the performance of rubber-plastic modified asphalt has improved. There is a mutual promotion mechanism between rubber and plastic in asphalt, which makes the performance of rubber-plastic modified asphalt better than that of asphalt obtained by a single modification method (rubber modified asphalt or plastic modified asphalt). In some properties, it can be close to the commercial SBS modified asphalt. The performance of rubber and plastic composite modified asphalt at high temperature has been generally recognized by researchers, but its low-temperature performance is still controversial. Therefore, it is recommended to apply in high-temperature areas. Future work should focus on the development of composite modifiers with stable performance, low cost and ease of use, standardization of modification processes, improvement of low-temperature performance, and monitoring of road performance and environmental impact.

【Objective】The seed germination of Nicandra physaloides was seriously affected by external colloid. The study was conducted in order to explore the effects of different hormone treatments on germination of N. physaloides seeds and increase the seed germination rate.【Method】The seeds of N. physaloides were used as test materials, and the random block method was used to set 4 ℃ low temperature treatment with seeds put on gauze and MS medium treatments of gibberellin (GA3), 6-benzylaminopurine (6-BA) and naphthylacetic acid (NAA), and the results of the four treatments were regularly observed and recorded.【Result】Compared with the normal temperature control, low temperature treatment at 4 ℃ on gauze significantly promoted the germination of N. physaloides seeds, and the highest germination rate was 25% after 48 h of treatment. The germination rate and germination index of N. physaloides seeds treated with 10 mg/L GA3 were 92.00% and 9.58, which were 4.27% and 1.33 higher than those of CK, respectively. The germination rate of the seeds treated with 1 mg/L 6-BA was the highest as 96.63%, and the germination potential of the seeds treated with 2 mg/L 6-BA was the highest as 73.33%, which were 8.9% and 10.07% higher than those of CK, respectively. The germination rate of the seeds treated with 1 and 2 mg/L NAA was 88.86%, but both the germination potential and germination index were lower than CK. Compared with CK, 10 and 50 mg/L GA3 treatment significantly increased hypocotyl length, while 6-BA and NAA treatments significantly decreased hypocotyl length.【Conclusion】Low temperature treatment can significantly promote the germination of N. physaloides seeds, and low concentration hormone treatment on MS medium can improve the germination rate of N. physaloides seeds. Through comprehensive comparison of germination rate, germination potential, germination index and hypocotyl length, the best hormone treatment for N. physaloides seeds is MS + 10 mg/L GA3.

Soft feel coatings applied over plastic substrates are widely used in automotive interiors and consumer products. These coatings provide a luxurious look and leather-like texture to hard plastic surfaces. Traditionally, two-component solvent-based polyurethanes have been used in these applications. In recent years, waterborne polyurethane formulations with lower volatile organic compounds have become the choice for soft feel coatings. In this article, the development of soft feel coatings with waterborne polyurethane technology will be presented. The performance of soft feel coatings based on waterborne polyisocyanates with polyester, acrylic polyols, and/or polyurethane dispersions will be discussed. [ABSTRACT FROM AUTHOR]