Hydrophilic or hydrogel carrier systems

Abstract From the Canadian patent

Improved active agent systems with novel carriers as membrane, release, and coating polymers for said active agents; the polymers are water absorptive polyurethane polymers prepared from resins having a low ratio of carbon to oxygen to nitrogen or having ionic, quarternary ammonium or salt groups in the resin backbone and a low amount of isocyanate; the water absorbtivity of the polyurethane polymers is above 10%, preferably above 20%, and these polymers may range to completely gel-like, high water absorbtive polymers; these active agent polymers are useful as in medicinal insecticidal, pesticidal, algaecidal, etc. applications; as well as zero release agents, body implants and coatings …