INTRODUCTION TO UHMWPE
UHMWPE, short for ultra high molecular weight polyethylene, is also known as high modulus polyethylene (HMPE) or high performance polyethylene (HPPE).
UHMWPE is a thermoplast and has extremly long molecular chains. Despite relatively weak Van der Waals bonds between the molecules, this results in UHMWPE being a very tough material, with the highest impact strength of any thermoplast presently made.
UHMWPE is highly resistant to corrosive chemicals, with exception of oxidizing acids. Furthermore, it has extremely low moisture absortption, a very low coefficient of friction, is self-lubricating and highly resistant to abrasion (15 times more resistant to abrasion than carbon steel.
The simple structure of the molecule gives rise to surface and chemical properties that are rare in high-performance polymers. For example, the polar groups in most polymers easily bond to water. Because olefins have no such groups, UHMWPE does not absorb water readily but is also does not get wet easily, which makes bonding it to other polymers difficult. For the same reason, skin does not interact with it strongly, making the UHMWPE fiber surface feel slipery.