2017 Volume 29 Issue 3 Pages 67-74
When polyethylene pipes are used for hot water application of tap water and heating, they contain a large amount of antioxidants so that they can endure high temperature for a long time.
In addition, some pipe manufacturers add extra antioxidants to the pipes for the purpose of prolonging the lifetime, but in many cases, the pipes don’t last as long as they expect. These days, when polymerizing the material of PE pipe for hot water application, they are starting to use Metallocene catalyst as an alternative to Ziegler-Natta catalyst, which has been conventionally used as a good method. In this study, we molded the material (non-cross linked) into PE pipe for hot water application and assessed its durability in hot water circulation test, which provides a similar situation to actual usage environment. Then we examined the influence of the resin structure on the speed of the antioxidant consumption based on the results obtained.
