Open to two or more interpretations; or of uncertain nature or significance; or (often) intended to mislead. Synonyms: ambiguous; equivocal. Context examples:
Polypropylene, also know as polypropene is a form of plastic just as polyethylene is. What separates polypropylene from polyethylene for starters is the fact that polypropylene can be molded in essence becoming pliable above a certain temperature. When it cools it will return to its solid state.
The major difference between these pipes is basically the difference in material and there properties. PVC, CPVC, UPVC and HDPE are non metalic pipes. They are made from thermoplastic materials. These fall under the category of Plastic pipework. Both pipes and fittings are available in these materials.