Parvovirus B19, which causes fifth disease in humans, is a member of the Erythrovirus genus of the Parvoviridae. Prior to 2014, it was also the name applied to a genus within the subfamily Parvovirinae, but this has been amended to genus Protoparvovirus to avoid confusion between taxonomic levels.
PVC redirects here. For other uses, see PVC (disambiguation). Polyvinyl chloride (/ËpÉlivaÉªnÉl ËklÉÉraÉªd/), more correctly but unusually poly(vinyl chloride), commonly abbreviated PVC, is the world's third-most widely produced synthetic plastic polymer, after polyethylene and polypropylene. PVC comes in two basic forms: rigid (sometimes abbreviated as RPVC) and flexible.
There are two main types of plastics â. Thermoplastics which are softened by heat and can be moulded. (Injection moulded, blow moulded or vacuum formed). Good examples are acrylic, polypropylene, polystyrene, polythene and PVC. Thermosets which are formed by ha heat process but are then set (like concrete) and cannot change shape by reheating. Good examples are melamine (kitchen worktops), Bakelite (black saucepan handles), polyester and epoxy resins.