PP (Co-Polymer)
Polypropylene copolymer (PPC) is a bit softer than homopolymer but has better impact strength, is also tougher and more durable. Copolymer polypropylene tends to have better stress crack resistance and low temperature toughness than homopolymer at the expense of quite small reductions in other properties.
A large number of end use applications for PP are possible by tailoring grades with specific molecular properties and additives during its manufacture.
PP Homo-Polymer
Polypropylene Homopolymer (PPH) is the more widely utilized than co-polymer and also offers a higher strength to weight ratio and is stiffer and stronger. This combined with good chemical resistance and weldability allows this material to be used in many corrosion resistant structures.
Compared to low or high density polyethylene, it has a lower impact strength, but superior working temperature and tensile strength. Noted for its excellent chemical resistance in corrosive environments, polypropylene provides excellent resistance to organic solvents, degreasing agents and electrolytic attack. It is light in weight, resistant to staining, and has a low moisture absorption rate.
PP Random Co-Polymer
Random copolymer PPs were developed to combine improved clarity and impact strength, and are used in blow moulding, injection moulding, and film and sheet extrusion applications. They are used in food packaging, medical packaging, and consumer products.
This thermoplastic material is produced through the polymerization of propylene, with ethylene links added to the polymer chain. Typical characteristics of Random Copolymer Polypropylene are excellent transparency and gloss, good aesthetics, radiation resistance, a low melting point and seal initiation temperature.