SLOW CRACK GROWTH RESISTANCE OF NON-VIRGIN POLYMERS

Papers # 2018 Las-Vegas

In order to improve the circular economy of polymers in terms of sustainability and reduced carbon footprint, the increased use of recyclates has become a topic of major importance. Due to their long design lifetimes, pipe applications represent an excellent opportunity to create added value to non-virgin polymers. In this context, special attention must be paid to the resistance of such materials against slow crack growth (SCG) which is the essential material property for structural long-term performance of 50 years or even more. The current paper demonstrated the applicability of the Cyclic Cracked Round Bar (CRB) Test according ISO 18489 for a quick and sensitive SCG characterization and material ranking of different non-virgin PE, PP and PVC. Moreover, by systematical mixing of PE and PP it is shown that already a small amount of polymeric impurity has a big impact on the long-term relevant resistance against SCG.

Related keywords : Slow crack growth, lifetime, recyclates, testing, sustainability, circular economy.
Please note that the whole article content is available on PPCA website onlySource : 2018 Las-Vegas


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