Accelerated weathering testing of polypropylene tank materials

Abstract

Polypropylene expansion tanks have been subjected to accelerated weathering testing according to the developed procedure of accelerated weathering testing. The objective of the study was to determine an arbitrary lifetime of tanks under operating conditions at higher temperatures, humidity, and UV radiation (climate regions of India and Venezuela). As a result of the studies of the polypropylene expansion tanks the following has been established: the failure of the both tank types (A and B) occurred in the area of the weld in the upper and lower part after four arbitrary years of accelerated weathering testing; the stress-strain behaviour in the outer tank walls is influenced by the interior structure of the partitions. The tanks with a larger opening in the partitions feature significant deformations when the inner pressure increases as a result of a higher temperature; the “sensitive indicators” of ageing and failure of the tank material have been found: elongation at break, flexural modulus, and impact strength.