PVC

What is PVC?

PVC, polyvinyl chloride, is only one member of the vinyl family of homopolymers and copolymers. PVC is produced in a wide variety of forms: from clear thin flexible sheet used in seat covers, to rigid thick sheet used in corrosion resistant applications Because of the extensive selection of different types of PVC, only rigid sheet will be reviewed here.

PVC is the oldest sheet product in the market used for corrosion resistant tanks, ducts, fume hoods, and pipe. Additionally, PVC has excellent chemical resistance, excellent electrical properties, low moisture absorption, good dimensional strength, and good compressive strength. When these properties are coupled with PVC’s flame resistance, chemical bondability, and thermoweldability, it is easy to understand why PVC is so frequently the material of choice in the corrosive resistant industry.

The major disadvantages of PVC are poor weatherability, relatively low impact strength, and fairly high weight for thermoplastic sheet (specific gravity 1.35). It is easily scratched or marred, and possesses a relatively low heat distortion point (160¡).

Unplasticized PVC is produced in two major formulations: Type I (corrosion resistant) and Type II (high impact).

Type I PVC is the most commonly used PVC, but in applications where higher impact strength than that offered by Type I is required, Type II offers better impact properties with a slight loss in corrosion resistance. In applications required a high temperature formulation, PVDF is usable to approximately 280¡F.