Main-Product

CPVC is a PVC Homopolymer that has been subjected to a Chlorination Reaction. Typically, Chlorine and PVC react according to a basic Free Radical Mechanism, brought about by various approaches using thermal and/or UV energy. The Chlorine Content of base PVC can be increased from 56.7% to as high as 74%; typically, most commercial CPVC Resins are measured to contain 63% to 69% Chlorine.^[1]

As the Chlorine Content in CPVC is increased, the glass transition temperature (Tg)—temperature region where the Polymer transitions from hard, glassy Material to a soft, rubbery Material—increases significantly. It’s the additional Chlorine Molecules that protect the Polymer’s Carbon Backbone, which in turn protects its structural integrity against heat. The increased heat resistance allows CPVC to perform at higher operating pressures than PVC.^[1]

CPVC is recognised as an important Engineering Thermoplastic due to qualities such as:^[1]

• High glass transition temperature
• High heat distortion temperature
• Chemical inertness
• Outstanding mechanical, dielectric, and flame and smoke properties
• Relative low cost to manufacture and install

CPVC is used in high-temperature Plastic Pressure Piping System introduced for potable Plumbing in 1959. It has also been used extensively in Fire Sprinkler Systems since 1985. This Material is also used for many Industrial and Process Piping Applications (Fig. 1).^[2]

Figure 1 - CPVC Piping System Components^[3]

1. Corzan^® MATERIAL & PIPING SOLUTIONS, What is CPVC?, corzan.com

2. PPI Plastic Pipe Institute, CHLORINATED POLYVINYL CHLORIDE (CPVC), plasticpipe.org

3. Hawkins, CHLORINATED POLYVINYL CHLORIDE (CPVC) PIPEWORK: THE PROBLEMS, hawkins.biz