Polyvinyl Chloride (PVC) (CAS: 9002-86-2) is a thermoplastic polymer that is widely used in many industries due to its unique properties, such as durability, strength, and resistance to chemical and environmental degradation. It is commonly used in the construction industry for pipes and fittings, as well as in the production of window frames and electrical cables. PVC is also used in the manufacturing of clothing, upholstery, and inflatable products.

It is the world’s third-largest thermoplastic by volume after polyethylene and polypropylene.

It is a white, brittle solid material available in powder form or granules. PVC is now replacing traditional building materials in several applications. These materials include wood, metal, concrete, rubber, ceramics, etc. in several applications. This is due to its versatile properties such as:

• lightweight,
• durable,
• low cost, and
• easy processability.

What are the basic forms of PVC?

Polyvinyl Chloride is widely available in two broad categories: Flexible and Rigid. But there are more types like CPVC, PVC-O and PVC-M.

Plasticized or Flexible PVC (Density: 1.1-1.35 g/cm3): Flexible PVC is formed by the addition of compatible plasticizers to PVC which lower the crystallinity. These plasticizers act like lubricants resulting in a much clearer and flexible plastic. This type of PVC is sometimes called as PVC-P.

Unplasticized or Rigid PVC (Density: 1.3-1.45 g/cm3): Rigid PVC is a stiff and cost-effective plastic. It shows high resistance to impact, water, weather, chemicals and corrosive environments. This type of PVC is also known as UPVC, PVC-U or uPVC.

Chlorinated Polyvinyl Chloride or perchlorovinyl: It is prepared by chlorination of PVC resin. High chlorine content imparts high durability, chemical stability and flame retardancy. CPVC can withstand a wider range of temperatures.

Molecular Oriented PVC or PVC-O: It is formed by reorganizing the amorphous structure of PVC-U into a layered structured. Bi-axially oriented PVC has enhanced physical characteristics (stiffness, fatigue resistance, lightweight, etc.).

Modified PVC or PVC-M: It is an alloy of PVC formed by addition of modifying agents, resulting in enhanced toughness and impact properties.

What are the key properties of PVC?

PVC is a very versatile and cost-effective material. Its main properties and benefits include:

• Electrical Properties: PVC is a good insulation material. Thanks to its good dielectric strength.

• Durability: PVC is resistant to weathering, chemical rotting, corrosion, shock, and abrasion. It is the preferred choice for many long-life and outdoor products.

• Flame Retardancy: Because of its high chlorine content, PVC products are self-extinguishing. Its oxidation index is ≥45. Antimony trioxide has been extensively used in combination with phosphate ester plasticizers. This gives excellent fire performance and mechanical properties.

• Cost/Performance Ratio: PVC has good physical as well as mechanical properties. It also provides excellent cost-performance advantages. It has a long life span and needs low maintenance.

• Mechanical Properties: PVC is abrasion-resistant, lightweight, and tough.

• Chemical Resistance: PVC is resistant to all inorganic chemicals. It has very good resistance against diluted acids, diluted alkalis, and aliphatic hydrocarbons. Some grades are attacked by:

• ketones and esters,
• chlorinated and aromatic hydrocarbons,
• aromatic ethers and amines, and
• nitro-compounds