Modified regeneration of waste plastics

The modified regeneration of waste plastics refers to the modification of waste plastics by chemical or mechanical methods. The modified recycled product has improved mechanical properties and can be used as a higher grade product.

The Industrial Technology Research and Development Laboratory in Takarazuka, Japan, invented a method for processing waste paper and waste polyethylene into synthetic wood. This synthetic wood can be processed like natural wood and has the same texture as natural wood. The Clayton Polymer Research Center in Australia has developed a process for the production of wood substitutes for the construction industry using polyethylene film scrap and waste paper fibers. The process is carried out in a twin-screw extruder. Process temperature Below 200 °C, fiber degradation can be avoided. The appearance, density and mechanical properties of newsprint/polyethylene composites produced by this method are similar to those of hard fiberboards. Standard tools can be used for cutting and forming. The crack resistance during nailing is also good, and the waterproof performance is better than that of hardboard. The "Ainmu" technology of Xishao Zhenfu used dry grinding to achieve the recycling of plastic waste, using recycled waste wood such as PE, PP, PVC, ABS, etc., to produce new types of wood with a wood chip content of more than 50%. The advent of Ein Wood's technology has aroused the concern of all countries in the world, especially the developed countries, and has generated strong repercussions.

In terms of chemical additives, Ciba-Gerky produces a blending aid containing antioxidants, co-stabilizers, and other active and non-active additives that can restore the performance of recycled materials to the original level; there are also people in the Netherlands. Developed a new chemical compatibilizer that can bond recycled plastics containing different polymers together. The United States reported that Solid State Shear Pulverization (S3P) is used for mechanical processing. Without heating and melting, the resins can be sheared at the molecular level to form mutually compatible blends. Most of the blends are Consisting of HDPE and LLDPE, the ultimate tensile strength and flexural modulus are comparable to those of HDPE and LLDPE. Solid-phase shear extrusion, reactive blending, multi-sandwich injection molding, and reactive extrusion in the last two years have made it possible to recycle waste plastics that are difficult to recycle.