Methods of identifying different plastics
1. Density method: By examining the density of various plastics and using liquid as a medium to see their ups and downs, the category of plastics can be roughly distinguished. Assuming that plastics can float on the surface in water, it can be determined that the raw material is not PVC.
2. Combustion method: observe the color of the flame and the smell and smoke emitted during burning by burning plastic. Generally, the burning flame of polyolefin materials is mostly blue or light blue, the smell is relatively mild and light, and the smoke is white, and most of them are Benzene or chlorine is easy to emit black smoke after burning, and the smell is strong, ABS is just that. In addition, such as PE and PP have dripping burning phenomenon, while PVC etc. have no dripping burning, but have self-extinguishing phenomenon.
3. Optical method: Identify by observing the transparency of raw materials. Commonly used transparent raw materials are: PS, PC, PMMA, AS; semi-transparent raw materials are: PE, random copolymer PP, homopolymer PP, soft PVC, transparent ABS, etc. , The other raw materials are basically opaque.
4. Color discrimination method: Generally speaking, raw materials without additives, if they contain double bonds, the color will be slightly yellow, such as ABS, because of the copolymerization of butadiene, the polymer still contains double bonds after polymerization. Therefore, it will be slightly yellow.