What are the basic forms of PVC film?

Polyvinyl chloride (PVC) is an economical and versatile thermoplastic polymer widely used in the building and construction industry for the production of door and window profiles, pipes (drinking water and wastewater), wire and cable insulation, medical devices, and more. The third-largest thermoplastic material by volume after polyethylene and polypropylene. It is a white, brittle solid material available in powder or granule form. Due to its lightweight, durability, low cost, and ease of processing, PVC is now replacing traditional building materials such as wood, metal, concrete, rubber, ceramics, etc. in a variety of applications.

PVC was first made "unintentionally" by German chemist Eugen Baumann in 1872. He exposed vinyl chloride gas sealed in a tube to sunlight and produced a white solid called PVC. It was not until 1913 that German chemist Friedrich Klatte obtained the first PVC patent for his method of polymerizing vinyl chloride using sunlight. By World War I, Germany was producing many flexible and rigid PVC products for use as a replacement for corrosion-resistant metals.

PVC is widely available in two broad categories: flexible and rigid. But there are many more types like CPVC, PVC-O, and PVC-M.

1. Plasticized or soft PVC (density: 1.1-1.35 g/cm3): Soft PVC is made by adding a compatible plasticizer to PVC to reduce the crystallinity. These plasticizers act like lubricants, resulting in clearer and more flexible plastics. This type of PVC is sometimes called PVC-P.

2. Unplasticized or rigid PVC (density: 1.3-1.45 g/cm3): Rigid PVC is a rigid and cost-effective plastic that is resistant to shock, water, weather, chemicals, and corrosive environments high resistance. This type of PVC is also known as UPVC, PVC-U, or uPVC.

3. Chlorinated polyvinyl chloride or perchloroethylene: obtained by chlorination of PVC resin. High chlorine content imparts high durability, chemical stability, and flame retardancy. CPVC can withstand a wider temperature range.

4. Molecularly oriented PVC or PVC-O: It is formed by the reorganization of the amorphous structure of PVC-U into a layered structure. Biaxially oriented PVC has enhanced physical properties (stiffness, fatigue resistance, lightweight, etc.).

5. Modified PVC or PVC-M: It is a PVC alloy formed by adding modifiers to improve toughness and impact properties.