Polyethylene having a molecular weight of 1.5 million or more is referred to as "ultrahigh molecular weight polyethylene (UHMW-PE)". Only ultra-high molecular weight polyethylene (UHMW-PE) with a molecular weight of more than 1.5 million is widely used as an engineering plastic because of its excellent physical properties.
Ultra High Molecular Weight Polyethylene (UHMW-PE) is the only new thermoplastic engineering plastic that combines many excellent properties:
1, wear resistance:
(In all current engineering plastics, UHMW-PE has the best wear resistance, the most eye-catching, even more than many metal materials (such as carbon steel, stainless steel, bronze, etc.) UHMW-PE wear resistance than nylon (PA 66 and PTFE are 4 times higher, 7 times higher than carbon steel, and 20% higher than steel pipe transmission efficiency. UHMW-PE pipe has a service life of 4-6 under strong corrosion and high wear conditions. Double, and improve the transmission efficiency by 20%, fully demonstrating the superiority of “energy saving, environmental protection, economy and high efficiency”
2, impact resistance: UHMW-PE impact resistance is the first in plastics, impact strength is among the best in all engineering plastics. Whether it is a strong external impact or internal pressure fluctuations, it is difficult to crack it.
3, anti-aging: stable performance, good aging resistance, ground and underground can be buried, 50 years without aging. According to the ASTM method (load 4.6kg/cm2), the heat distortion temperature is 85 ° C, the use temperature can reach 90 ° C, in special cases, it is allowed to use at higher temperatures.
4, electrical performance: large volume resistance, up to 1017-18SL-CM,
(>1E12ohm), breakdown voltage up to 50KV/MM, dielectric constant is 2.3. Suitable for use as structural materials for electrical engineering over a wide range of temperatures and frequencies
5, self-lubricating: has a very low coefficient of friction (0.05-0.11), so the self-lubricating is excellent, the dynamic friction coefficient can be seen from the table is 1/2 of PA66 and POM under water lubrication conditions, under no lubrication conditions Second only to self-lubricating, the best polytetrafluoroethylene (PTFE), when it is operated in sliding or rotating form, is more lubricious than steel and brass added lubricants, so it is known as cost performance in the field of tribology. Ideal friction material
6. Chemical resistance: It has excellent chemical resistance. In addition to strong oxidizing acid, it can withstand various corrosive media (such as acid, alkali, salt) and organic media at a certain temperature and depth. Except for hydrazine solvent, it is stable in concentrated hydrochloric acid at 80 ° C, concentrated sulfuric acid at 75%, and nitric acid at 20%. After immersing for 30 days in 80 organic solvents at 20 ° C and 80 ° C, there is no abnormality in appearance and almost no change in other physical properties.
7. Impact energy absorption: UHMW-PE has excellent impact energy absorption, and the impact energy absorption value is the highest among all plastics, so the noise damping is very good and has excellent noise reduction effect.
8. Low temperature resistance: UHMW-PE has excellent low temperature resistance and is ductile at liquid helium temperature (-269 °C), so it can be used as a low temperature resistant component for the nuclear industry. It is worth noting that it also maintains excellent impact strength in liquid nitrogen (-196 ° C), a feature not found in other plastics.
9, health non-toxic: UHMW-PE health and non-toxic. In the food processing industry, UHMW is utilized for its self-lubricating properties, easy purification, low odor, taste transfer and boiling water resistance. It is fully compliant with the standards of the Japan Health Association and is approved by the US Food and Drug Administration and the US Department of Agriculture and has met FDA and USDA requirements. Can be used to contact food and medicine, and can replace expensive stainless steel materials
10, non-stick: UHMW-PE surface adsorption is very weak, its adhesion resistance is second only to the non-sticky PTFE in plastic, so the surface of the product is not easy to adhere to other materials.
11. Water repellency: UHMW-PE has a very low water absorption rate, generally less than 0.01%, which is 1% of PA66. Therefore, it does not need to be dried before molding, and the product will not change in size due to moisture absorption in a humid environment.