1, polypropylene is a non-toxic, tasteless and odorless high crystalline polymer with a density of only 0.90-"0.9 1g/cm3, which is one of the lightest varieties of all plastics at present.

2. Polypropylene also includes a copolymer of propylene and a small amount of ethylene. Usually a translucent colorless solid, tasteless and nontoxic.

3. Due to its regular structure and high crystallinity, its melting point can reach 167℃. Its outstanding advantages are heat resistance and corrosion resistance, and the product can be sterilized by steam. Low density, it is the lightest general plastic. The disadvantages are poor impact resistance at low temperature and easy aging, but they can be overcome by modification respectively.

4. The chemical stability of polypropylene is very good, except that it can be corroded by concentrated sulfuric acid and concentrated nitric acid, and it is relatively stable to other chemical reagents. However, low molecular weight aliphatic hydrocarbons, aromatic hydrocarbons and chlorinated hydrocarbons can soften and swell polypropylene, and at the same time, its chemical stability is improved with the increase of crystallinity, so polypropylene is suitable for making various chemical pipelines and fittings with good anticorrosion effect.