Ultra-high molecular weight polyethylene

UPE, that is, ultra-high molecular weight polyethylene, English name Ultra-high molecular weight polyethylene, is a thermoplastic engineering plastic with a molecular weight higher than 1.5 million. The molecular chain length is 10-20 times that of HDPE, and the longer molecular chain (higher molecular weight) gives UHMWPE the main advantages of toughness, wear resistance, stress crack resistance, etc., because it is a kind of polyethylene, UHMWPE It also has the lubricity, chemical resistance and excellent electrical properties of general HDPE. Its successful development is generally regarded as one of the top ten scientific and technological achievements in the 20th century.

UPE board has excellent wear resistance, good low temperature impact resistance, self-lubrication, non-toxic, water resistance, chemical resistance, heat resistance is better than ordinary PE, the disadvantage is low heat resistance (heat deformation temperature), processing Poor formability, outer surface hardness, rigidity, toughness and creep resistance are not as good as general engineering plastics, and the expansion coefficient is too large. UHMWPE has poor fluidity and extremely high viscosity in the molten state. It is a rubber-like, high-viscosity elastomer. In the early days, only pressing, sintering and other methods can be used for molding, and extrusion, injection molding, blow molding and other methods can also be used for processing. The mechanical properties are higher than that of ordinary high-density polyethylene.

The operating temperature is 100 to 120°C. Good cold resistance, can be used at -180 ℃. The product has a density of 0.935g/cm3, a molecular weight of 8 million, a tensile strength at break of 40MPa, an elongation at break of 350%, and a flexural modulus of 600MPa. Izod notched continuous impact. Wear (MPC method) 20 mm.

UPE board has many excellent properties. However, few people know such excellent engineering plastics. This is mainly due to insufficient research on the melt properties of ultra-high molecular weight polyethylene, and the processing methods are basically backward. According to the sintering process. In recent years, with the continuous development of ultra-high molecular weight polyethylene processing technology, its products have been successfully used in many fields.