How to identify high quality uhmw polyethylene sheet?
Uhmw polyethylene sheet has excellent wear resistance, good low temperature impact resistance, self-lubricating, non-toxic, water and chemical resistance, heat resistance is worse than general PE, outer surface hardness, rigidity, creep resistance is not as good as general Engineering plastics, the expansion coefficient is too large. uhmw sheet has poor fluidity and high viscosity in molten state. It is a rubber-like high-viscosity elastomer. It can only be formed by pressing and sintering methods in the early stage, and can also be processed by extrusion, injection molding and blow molding.
At present, there are many types of uhmw polyethylene sheet on the market, and the quality is uneven. But how to identify high-quality ultra-high molecular weight polyethylene wear plates from these products? This should be the most concerned issue for the majority of users.
1. Bending and Resolving Method: Cutting a small strip of product and then repeatedly folding the UHMWPE sheet by hand will have excellent toughness and will not break if it is broken into other products.
2. Fingernail scratching method: The product with the closest appearance to the uhmw polyethylene sheet is the high-density polyethylene sheet, which can only be distinguished by scratching. The ultra-high molecular weight polyethylene sheet has higher molecular weight and higher hardness. The uhmwpe board is less rigid. If it is scratched with a nail, it is a uhmw polyethylene sheet.
3. Water-floating method: The ultra-high molecular weight polyethylene wear-resistant lining plate should be floating in the water between 0.93-0.98. If it is submerged, it is neither ultra-high molecular weight polyethylene sheet.
The wear resistance of uhmw polyethylene sheet is the crown of plastic and exceeds some metals. Compared with other engineering plastics, the abrasive wear index of UHMWPE is only 1/5 of PA66, 1/10 of HEPE and PVC; compared with metal, it is 1/7 of carbon steel and 1/27 of brass. Such a high wear resistance makes it difficult to test the degree of wear resistance by the general plastic abrasion test method, and thus a mortar abrasion test device is specifically designed. The wear resistance of UHMWPE is proportional to the molecular weight, and the higher the molecular weight, the better the wear resistance.
