Plastic Pipes Conference Association # 1998 Gothenburg
Nezbedova, Salajka, Kucera
Structural and morphological parameters together with processing conditions determine the type of fracture behaviour of polyethylenes. Long time brittle failure which occurs under low stresses and at room temperature limits the lifetime of polyethylens used as pipes for water and gas distribution. In order to optimise the lifetime of such pipes, it is necessary to apply methods for comprehensive understanding of their structure and fracture properties.
The accelerated PENT and NPT tests were used to determine fracture parameters PE resins. Structural changes during processing conditions were characterised by SIS/DSC method.
The correlation between fracture and structural parameters has been found.
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