Material Science RCP
Plastic Pipes Conference Association # 2006 Washington DC
Krishnaswamy, Leevers, Lamborn, Sukhadia, Register, Maeger
The influence of molecular architecture on the rapid crack propagation (RCP) resistance of a wide variety of high-density polyethylene (HDPE) pipes was investigated. It was concluded that high molecular weight, high crystallinity and a relatively narrow molecular weight distribution are important architectural attributes for RCP resistance. The ductile-brittle transition temperature, as measured on compression-molded specimens using the razor-notched Charpy impact test, appears to be a reasonably good indicator of the RCP resistance of the resultant pipes. Finally, the uniformity of carbon black dispersion was also found to influence the RCP performance of the pipe.
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