One of the most commonly used materials for extrusion is polyvinyl chloride, more commonly known as PVC. It is a thermoplastic polymer used worldwide. Globally, more than 50 percent of manufactured PVC is used in the construction industry. Most of it went through the process called PVC extrusion.
PVC extrusion is the most usual way of turning PVC into useful building materials. PVC is inexpensive and is very easy to assemble. Lately, PVC has been replacing wood, clay, concrete and other traditional building materials on many parts of the globe. It is still widely used, despite the many claims of adverse effects to human health and natural environment.
The most common PVC extrusions include window profiles, vinyl siding, plumbing, pipe, and conduit fixtures. It is usually the material of choice for pipelines in the sewer and water industries because it is very flexible and cheap. Other common PVC extrusions include hoses, tubing, roofing membranes, flooring, and electrical wire and cable insulation.
Most electric wires are coated with insulation made of PVC and produced through extrusion. PVC extrusions make the wires fire-retardant. Although it also produces HCl fumes that can pose a health hazard, HCl breaks down easily on surfaces, specifically in areas where the air is cool. This makes it unlikely that these fumes will be inhaled.
PVC extruded pipes are very widely used. They account for more than 65% of the water distribution market in the United States alone. In sanitary sewer pipe applications, they constitute 75 percent. While PVC is believed to pose health and environmental hazards, CPVC or chlorinated polyvinyl chloride has been approved in the US since 1982. In some countries like the Netherlands and Germany, using PVC extrusions is discouraged by local authorities due to environmental problems that they cause.
Aside from being cheap, PVC is also a recyclable material. In fact, in Japan and Europe, a new process of recycling PVC is being developed.