| 摘要 |
<p>Polysiloxanes of uniform molecular weight (MW) distribution with 500-10,000 MW segments of polysiloxane and containing at least one vinyl group connected to said polysiloxane segments through intervening alkylene-urea or -urethane linkages are prepared from polysiloxane-polyols, -polyamines or -polythiols by reaction with an unsaturated compound containing an isocyanato moiety, for example 2-isocyanatoethyl methacrylate. The polysiloxanes containing the vinyl groups are useful as radiation- or thermally curable coatings for glass, textiles, plastics, wood, ceramics, metals, as films or bandages for medicinal purposes, or molded shapes, in form of contact lenses, catheters or implants, either by themselves or in combination with other vinyl monomers; and are particularly useful in preparing hard or soft contact lenses, including hydrogel contact lenses.</p> |
