Toshiki SHIMURA, Shinobu KAWAGUCHI Kazumi NAKAYAMA, Tomoko WATANABE, Yoshito OHTAKE
Papers # 2012 Barcelona
To clarify the appropriate acceleration test method and the evaluation index for it, a series of acceleration tests was conducted on commercial poly-propylene (PP) pipe for outside use. Various tests and analyses were carried out on degraded PP pipes and these results were compared with PP pipe that had actually been used outside for about 2 years. The major result obtained were as follows : (1) the degradation mechanism for the PP pipe which was evaluated in this study was the scission of the molecular chain caused by oxidative degradation, (2) Xenon light irradiation and hot water spray exposure and the cycle process were applicable as the accelerated degradation conditions for the target of this evaluation, (3) the Initial Oxidation Temperature (IOT) is a valid lifetime evaluation index which can detect the signs of disintegration in molecular structure and can be obtained by simple analysis.
