Plastic Pipes Conference Association # 2012 Barcelona
Deslauriers Paul
(Key words : polyethylene, slow crack growth, primary structural parameter) In this paper molecular weight and SCB data obtained experimentally or digitally generated are combined into a single, primary structural parameter (PSP2) and used to rapidly screen the slow crack growth resistance of a variety of polyethylene resins. Our results show that PSP2 values obtained for resins made using different catalysts (both dual and single catalyst systems) and hence, different polymer architectures, correlate well with results obtained from several short-term tests (i.e., Tensile % NDR, PENT, SPNCTL, ESCR) as well as pipe hoop stress data. Furthermore, due to recent advancements in modeling the effects of structure on density, PSP2 values can now be generated for any digital MWD and SCB distributions (what if scenarios). The predictive ability PSP2 values and the use of this parameter to unravel structural affects on SCG in order to better design high performance pipe resins will be presented and discussed.
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