Polypropylene

There are 3 types of Polypropylene: homopolymer, random copolymer and copolymer. Polypropylene in both configurations offers excellent resistance to moisture and good chemical resistance of acids, alkalis and solvents. However, PP does not resist aromatic hydrocarbons such as benzene and chlorinated hydrocarbons such as carbon tetrachloride.
There are thermal and mechanical differences between the main chemical compositions. In fact, homopolymer polypropylene has a slightly higher density than the copolymer variant (respectively 0,905 and 0,897 g/cm3).This gives it a higher elastic modulus, hardness and resistance against maximal forces.
PP does not resist oxidation at high temperatures.
The PP does not absorb moisture but is permeable to the C02, for this reason is not used in beverage.