Copolymers of poly(vinyl trifluoroacetate) or poly(vinyl alcohol), process for preparing poly(vinyl alcohol) copolymers and process for preparing shaped articles from such copolymers.

摘要

Novel, non-crosslinked copolymers of vinyl trifluoroacetate (VTA) and up to 5 weight percent of the VTA of certain comonomers, such as vinyl esters or disubstituted ethylene monomers, are disclosed. Solvolysis of these copolymers provides novel water-insoluble, non-crossiinked, poly(vinyl alcohol) copolymers which can be hydrated to copolymers having controllably variable hydrogel properties and high strength. Such poly(vinyl alcohol) copolymers are particularly desirable as ocular devices such as contact lenses.;A process for preparing thermoformed articles including ocular devices using the copolymers of the invention is described.