Polyvinyl chloride (PVC) is a thermoplastic polymer produced from vinyl chloride monomers and characterized by the presence of chlorine atoms attached to the carbon backbone. The chlorine content increases intermolecular attraction between polymer chains, resulting in a material that is inherently more rigid and less flexible than many hydrocarbon-based thermoplastics such as polyethylene and polypropylene. In its unmodified form, PVC is a stiff, strong, and relatively brittle material; however, its properties can be widely adjusted through the use of plasticizers, stabilizers, and fillers, allowing it to span a broad range of applications from rigid structural products to flexible films and tubing.
From a product design standpoint, PVC is valued for its good chemical resistance, low moisture absorption, and durability in outdoor environments. Rigid PVC is commonly used in pipes, fittings, window frames, and electrical conduit, where dimensional stability and corrosion resistance are important. When plasticizers are added, the material becomes flexible and is used in products such as cable insulation, medical tubing, and flexible sheets. This ability to tailor stiffness and flexibility through formulation makes PVC particularly versatile for designers who must balance mechanical performance, environmental exposure, and cost.
PVC is readily processed by extrusion, injection molding, and thermoforming, supporting high-volume production of both rigid and flexible components. It also offers good electrical insulation properties and inherent flame resistance due to the chlorine in its structure, which can be advantageous in building and electrical applications. Designers should consider its moderate heat resistance and the potential effects of plasticizer migration in flexible formulations, but within its intended service range PVC provides a durable, chemically resistant, and economically efficient material option for a wide variety of engineered products.