Reinking, Mehta, Garrison, Joseph, Schwab
Developments in New Materials # 2006 Washington DC
Bimodal polyethylene (PE) pipe resins have demonstrated a step change in slow crack growth (SCG) and rapid crack propagation (RCP) resistance over conventional unimodal polyethylene resins. Literature shows that homopolymer polyethylene has higher RCP resistance than PE copolymers, which suggests a trade-off between SCG and RCP resistance. Efforts are currently underway to implement specifications for RCP into North American standards. The North American gas industry would like to see critical temperature specifications eventually implemented, which would require even higher resistance to RCP. Results from new technology are presented that demonstrate a step change in the RCP-SCG balance of bimodal polyethylene.