PVCU

PVCU, short for unplasticized polyvinyl chloride, is a rigid form of polyvinyl chloride used in construction and durable goods. In Europe the material is commonly marketed as uPVC or PVC-U. It differs from plasticized PVC (PVC-P), which uses plasticizers to increase flexibility.

PVCU is designed to resist weathering, chemicals, and UV exposure, providing stiffness, dimensional stability, and good thermal insulation. It contains stabilizers and other additives to enhance long-term performance and, because it contains chlorine, offers relatively good fire resistance for a plastic, though burning PVCU releases hydrogen chloride and other gases.

Production and processing: Vinyl chloride monomer polymerizes to form PVC resin, which is compounded with stabilizers, pigments, lubricants, and fillers. Most PVCU components are manufactured by extrusion and then assembled; window and door frames are extruded profiles, sometimes reinforced with steel or aluminum and joined by mechanical connections or solvent welding. Piping is also extruded and joined by solvent or mechanical fittings.

Applications: The largest uses are window and door frames, conservatories, cladding, and piping systems for drainage, venting, and water services. It is chosen for low maintenance, weather resistance, and cost advantages.

Environmental and regulatory aspects: PVCU is recyclable, but recycling requires separation of additives. Waste streams exist for construction products and piping. The chlorine content requires emissions controls in production and careful management at end of life. In the UK and parts of Europe the term PVC-U or uPVC is common; in other markets PVC-U is also used.