A new approach for a fast and relevant evaluation of environmental stress-crack resistance in polyethylene grades [PE]

With the increase of the environmental stress crack resistance (ESCR) of polyethylene pipe grades, the need for a fast, cheap and relevant analytical tool able to evaluate this property is a must. A \"TC138\" working group is actively looking for accelerated test methods and is considering new approaches. Inside Total, an analytical tool has been developed based on the following ideas  : - Thanks to rheological and small-scale mechanical analyses, measurements are available, containing information on polymer structure; - These analyses being sensitive to molecular parameters of importance for the ESCR properties, there must be a link between ESCR and performed small scale measurements. Such link is not precisely established from physico-chemical considerations. However, we have successfully tested that a statistical multivariable analysis allows establishing such correlation. This has been performed using a very broad range of polyethylene grades with various designs and catalyst platforms. The validity and the accuracy of this new approach, its interest both for a production quality control and for new product developments is presented and discussed.