Abstract: A degradable article comprising a polyurethane polymer gel or foam whose polymer structure contains hydrolytically unstable ester linkages and various additives. The article can be constructed so that some of the additives are released from the article at a sustained rate. In a preferred embodiment the additives are sensory stimulants for marine or aquatic organisms and the article is used as bait for those organisms. Such sensory stimulants can include high molecular weight thickeners, to impart a slippery texture.

Abstract: A prepolymer having a molecular weight of at least 3,000 is made from a polyether polyol where all the OH groups are capped with an aliphatic polyisocyanate. When mixed with water the prepolymer reacts to form an elastomeric cross-linked polyurethane gel adhesive which can be used to adhere fibers to from a nonwoven fabric. Examples of the aliphatic diisocyanate are IPDI (isophorone diisocyanate) and hydrogenated MDI. A catalyst can also be applied to the aqueous mixture to accelerate the adhesive binder formation.

Abstract: A sound deadening material is obtained with a very high loading of sound damping materials such as barium sulfate, calcium carbonate or metal powders. These materials are mixed with water and are bound together by adding a water-miscible isocyanate-terminated prepolymer which reacts with the water to form a cross-linked binder.

Abstract: Articles having increased fire-retardant properties are obtained by surrounding a foraminous core having the desired product properties with an adherent protective layer of a hydrophilic polyurethane foam having large amounts of fire-retardant fillers. The core can be made of rigid, semi-rigid or flexible foams. Preferable cores include conventional bedding and cushioning materials. The protective layer can be sprayed or poured as a coating or molded on to the core.

Abstract: An open cell polyurea polyurethane foamed sponge is produced by mixing together a resin and an aqueous pahse. The resin phase consists of a prepolymer made from a hydrophilic oxyalkylene polyol which is capped with isocyanate groups and from about 1-30% by weight of the prepolymer of a polymeric polysocyanate such as a PAPI resin. The aqueous phase contains water, reinforcing fibers, surfactants, a thickening agent and preferably up to 40% by weight of diatomaceous earth. The resulting foam has a reduced volume swell, rapid wet out and improved wet strength.

Abstract: Articles having increased fire-retardant properties are obtained by surrounding a foraminous core having the desired product properties with an adherent protective layer of a hydrophilic polyurethane foam having large amounts of fire-retardant fillers. The core can be made of rigid, semi-rigid or flexible foams. Preferable cores include conventional bedding and cushioning materials. The protective layer can be sprayed or poured as a coating or molded on to the core.

Abstract: A fire-retardant protective coating is produced by dissolving a water-soluble polyisocyanate prepolymer in either an aqueous slurry or solution of fire-retardant materials and/or intumescent materials. After mixing, the gel produced can be applied as a coating which is useful for protecting or holding together surfaces vulnerable to fire, heat, air or minor abrasion. After the water evaporates, the cross-linked polyurethane coating has a large solids content of the fire-retardant and/or intumescent materials uniformly dispersed throughout. Preferred prepolymers are liquid with a molecular weight greater than about 2,000 and are made of a random copolymer of ethylene oxide and other alkylene oxides with isocyanate capping.

Abstract: A fire-retarding polyurethane foam is applied to the interior surfaces of a mine such as mine shafts, entries and tunnels. The coating is applied by spraying a mixture of foam-forming ingredients including a hydrophilic polyoxyalkylene urethane prepolymer and a large amount of an aqueous slurry containing a phosphorous compound, alumina trihydrate and a char-forming material such as starch or wood cellulose. The foam coating acts as a protective sealant, and it can also be applied on other surfaces where insulation and fire retardancy are desired.

Abstract: The invention disclosed relates to hydrophilic polyurethane foam which exhibits improved tensile and tear properties and reduced shrinkage upon drying as a result of incorporation of substantially hydrophilic reinforcing fibers formed from homopolymers and copolymers of polyvinyl alcohol. The reinforced foams also exhibit reduced swelling upon contact with water.