The reason for low temperature and brittleness of PPR pipes

The application of PPR pipes is more and more general in nowadays. And it has played a very important role in pipe industry because of its advantage and feature. It is atactic polypropylene,namely -type polypropylene. It is obtained by random copolymerization of propylene monomer and a small amount of ethylene monomer under heating, pressure and catalyst. Ethylene monomer is randomly distributed in the long chain of propylene, ethylene monomer is generally controlled between 3-5%. The ethylene content and the polymerization of ethylene and propylene determine the characteristics of cold brittleness. In the case of low temperature, especially in the winter construction process, the flexibility at low temperature is reduced and the rigidity is enhanced, so the performance is brittle. Under the action of external force or too large accidental load, the cracking of the pipe may occur. It will bring inconvenience.Then the relevant national norms on this issue made a clear request. In winter construction, attention should be paid to the characteristics of low temperature and brittleness of PPR pipeline, and the corresponding construction scheme should be worked out.