Analysis of blending and utilization of waste polypropylene
PP/PE blend: Although recycled PP has higher mechanical strength and modulus than recycled PE, like the new PP resin, the impact resistance of recycled PP is particularly poor in stress crack resistance and poor in low temperature performance. These performance characteristics are determined by the PP aggregate structure and the macromolecular chain structure, and thus can be modified with polyethylene. When recovering PE (LDPE, HDPE) and PP blends, if there are more PP recycled materials, the alloy can be directly prepared; if 10% to 25% HDPE is blended in PP, the modified blend is - At 20 ° C, the falling ball impact strength is more than 8 times higher than PP, and the processing fluidity is increased, which is suitable for injection molding of large containers. Structurally, the addition of PE destroys the crystallization of PP such as large spheroidal crystals, and also reduces the crystallinity of PP; if EPDM is added to the system. (about 5%), can improve the compatibility of PP and PE, the strength is improved; adding a small amount of EPR rubber can also improve the impact properties of the material. PP/PVC blend: For PP regrind containing PVC, some CPE compatibilizer may be added to improve the performance of the blend. Recycling PP can be used to improve the molding fluidity of PVC products. If PVC: PP: EPDM: CPE is 100:10:20:20, the impact strength of the alloy can be maximized. For PE, PP, PVC ternary blends, in addition to the addition of compatibilizers CPE, EPR, alloys can also be prepared by reactive extrusion techniques. For example, the grafting reaction is carried out with maleic anhydride or maleate to increase the capacity. In this method, plasticization, grafting reaction and blending are carried out in a screw extruder, which can be completed at one time, and the screw length-to-diameter ratio of the screw extruder is required to be about 40, and there is an exhaust and a feed port in the middle, and the screw extruder It can be a single screw extruder or a twin screw extruder. Plastic wood products can also be produced by mixing such blends with wood flour. Mini Electric Screwdriver,Easy Out Kit,Home Tool Kit,Durable Screw Driver SUZHOU CREATION SPACE INTELLIGENT TECHNOLOGY CO.,LTD , https://www.mypkey.com