Towards a methodology for designing RCP-resistant polyethylenes using batch scale test methods [PE]

# 2010 Vancouver

This paper outlines a PE100 design methodology which gives central importance to the separate modelling and measurement of plane-strain and plane-stress dynamic fracture resistance. The former is difficult to measure but can be estimated from weight-average molecular weight; the latter is related to high-rate adiabatic tensile deformation which can be estimated from low-rate tensile test data. An overall dynamic crack resistance is then predicted as a function of temperature and pipe wall thickness. Meanwhile, employing a semi-analytical RCP model, the crack driving force is calculated as a function of temperature, pressure and pipe size. The outcome is an estimate of critical pressure as a function of temperature and, hence, of the critical temperature. The entire scheme is demonstrated using a group of experimental resins in the −20 to +10◦ C transition temperature range. Early results indicate the potential of the scheme for guiding PE100 resin design, while highlighting areas in which better modelling is needed.

Please note that the whole article content is available on PPCA website onlySource : 2010 Vancouver


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