Polypropylene is a type of thermoplastic polymer resin with the chemical formula C3H6. It is useful in many packaging applications as a structural plastic or as a fiber-type plastic. It is easy to customize, lightweight and very flexible, and has high melting point and a low level of electrical conductivity. Polypropylene (PP) is a versatile thermoplastic – it is the lightest polymers among all commodity plastics, low density, stress-cracking resistant and the list goes on. It is the second-most widely produced volume plastic after polyethylene.

Molecular Structure of polyproplene

Types of Polypropylene

Homopolymers and Copolymers are the two major types of polypropylene available in the market.

• • Polypropylene Homopolymer is the most widely utilized general-purpose grade. It contains only propylene monomer in a semi-crystalline solid form. Main applications include packaging, textiles, healthcare, pipes, automotive and electrical applications.

• Polypropylene Copolymer family is further divided into random copolymers and block copolymers produced by polymerizing of propene and ethane:

1. Polypropylene Random Copolymer is produced by polymerizing together ethene and propene. It features Ethene units, usually up to 6% by mass, incorporated randomly in the polypropylene chains. These polymers are flexible and optically clear making them suitable for applications requiring transparency and for products requiring an excellent appearance.

2. While in Polypropylene Block Copolymer, ethene content is larger (between 5 and 15%). It has co-monomer units arranged in regular pattern (or blocks). The regular pattern hence makes thermoplastic tougher and less brittle than the random co-polymer. These polymers are suitable for applications requiring high strength, such as industrial usages.