Abstract: The present invention relates to a method of making a coated substrate that requires a polyurethane/urea contact adhesive, and the coated substrates produced by this method. This invention requires a) a polyisocyanate with a functionality of less than about 4, b) optionally, a polyol blend consisting of about 95 to 100% polyether polyols with molecular weights from about 1800 to 12000 and average functionality from about 1.5 to about 4 and up to about 5% of chain extenders with molecular weights from about 60 to 400 and average functionality from about 1.5 to about 3, and c) polyethers having at least two isocyanate reactive groups and a molecular weight of from about 1800 to about 12000 and average functionality from about 1.5 to about 4 in which at least 50% of the isocyanate reactive groups are primary and/or secondary amino groups.

Abstract: This invention relates to a process for producing polyester-polyurethane compositions, and to the stabilization thereof in relation to hydrolytic ageing phenomena by an active ingredient combination comprising compounds containing carbodiimides with lactone derivatives, to mouldings produced therefrom and to the use thereof for semi-rigid, solid and/or cellular mouldings.

Abstract: The present invention relates to the use of hollow microspheres filled with a hydrocarbon, to introduce uniform cell geometries in syntactic foams having a bimodal cell structure. The rigid foam product includes from 20 to 80 percent by weight of the hollow microspheres, the microspheres having average diameters ranging from 80 to 200 microns. The microspheres are encapsulated from 80 to 20 percent by weight of a closed cell polyurethane foam, the cells of the foam having average diameters from 0.01 to 60 microns.

Abstract: The invention relates to a completely biodegradable hydrogel comprising polyester polyurethane polyurea containing urea groups as well as polysaccharides and/or their derivatives, the hydrogel containing plant material capable of dividing. The invention also relates to a process for the embedding of the biological material and the fabrication and shaping of the hydrogels from aqueous solutions. The hydrogels according to the invention may be used as coating material for embedding biological material capable of dividing, especially plant material, preferably plant cells, protoplasts, plant tissues and plant organs, as well as zygotic or somatic plant embryos, under sterile conditions for the purpose of protecting the material during storage, transport and handling. The hydrogels according to the invention may also contain further additives, for example, plant protection agents or nutrients. The embedded biological plant material according to the invention may be used as artificial seed.

Abstract: This invention relates to a process for the reduction of color of polymethylene poly(phenylisocyanates). This process comprises mixing a polymethylene poly(phenylisocyanate) with an epoxide having an epoxide equivalent weight of about 44 to about 700, and heating this mixture to a temperature of from about 35 to about 150.degree. C. for at least about 15 minutes, with stirring. Suitable epoxides include epoxidized fatty acid monoglycerides, epoxidized fatty acid diglycerides, epoxidized fatty acid triglycerides, epoxidized dimer fatty acids and epoxidized trimer fatty acids.

Abstract: A process for making a thermoplastic polyurethane material comprising the steps of casting an NCO-terminated prepolymer with 1,4-butanediol to form a casting composition; extruding the casting composition to form at least one strand of a polyurethane elastomer; pelletizing the at least one strand of said polyurethane elastomer to form at least one pellet; and processing the at least one pellet to form a thermoplastic article.

Abstract: This invention relates to processes for the production of symmetrical polyurea-urethane coated granular fertilizer products, and to the symmetrical polyurea-urethane coated granular fertilizer products produced by these processes. These processes comprise coating fertilizer granules with compounds which react to form urethane coatings which contain terminal isocyanate groups, followed by polymerization of these urethanes to form symmetrical polyurea-urethanes. Suitable compounds comprise a) an organic polyisocyanate component, and b) an alkanolamine component containing at least one tertiary amine group and at least one hydroxyl group. These compounds are present in sufficient quantities that the molar ratio of isocyanate groups to isocyanate-reactive groups is from about 1.6:1.0 up to about 10.0:1.0 in each encapsulating layer.

Abstract: This invention relates to an isocyanate composition comprising a) at least one isocyanate and b) from 1 to 50% by weight, based on the total weight of component a), of sulfur. These isocyanate compositions are suitable for the preparation of polyurethane/polyurea encapsulated fertilizers. Accordingly, the present invention also relates to an improved process for the production of a polyurea/polyurethane encapsulated fertilizer comprising applying at least one isocyanate-reactive component to the fertilizer particles and applying the isocyanate compositions of the present invention to the fertilizer particles, to form these polyurea/polyurethane encapsulated fertilizers.

Abstract: The invention relates to a process for preparing solid, transparent to translucent polyurethane molded items which, due to their elastic and optical properties, can be used, for instance, as an alternative material to rubber.

Abstract: This invention relates to a process for the production of a polyurethane backing and air frothed foam on a substrate comprising the steps of a) mixing a polyisocyanate and a polyol blend in the presence of a catalyst to form a reaction mixture, b) applying the reaction mixture to a substrate, and c) curing the reaction mixture to form a polyurethane backing an/or an air frothed foam on the substrate. Suitable catalyst compositions for the present invention include those corresponding to the formula: ##STR1## wherein: each R: independently represents a linear or branched C.sub.1 to C.sub.24 (preferably from 5 to 16 carbon atoms and most preferably from 8 to 12 carbon atoms) alkyl group, or a cyclic group containing from 4 to 24 carbon atoms (preferably from 5 to 16 carbon atoms and most preferably from 8 to 12 carbon atoms).

Abstract: The present invention relates to an improved process for the production of light colored polymethylene polyphenyl polyisocyanates. This process comprises adding a compound that contains an epoxide group to the process at any point prior to quench cooling the formed polyisocyanates.

Abstract: This invention relates to a novel trimerization catalyst system, and to a process for trimerizing organic polyisocyanates in the presence of thermally active catalyst systems. These catalyst systems comprise (A) compounds selected from the group consisting of (i) lithium salts of aliphatic or aromatic carboxylic acids, (ii) lithium salts of hydroxyl group containing compounds wherein the hydroxyl groups are directed attached to an aromatic ring, and (iii) lithium hydroxide; (B) an allophanate catalyst; and (C) an organic compound which contains at least one hydroxyl group.

Abstract: This invention relates to a novel freeze-stable allophanate modified toluene diisocyanurates, and to a process for producing these freeze-stable allophanate-modified toluene diisocyanurates which requires a catalyst which is capable of forming both trimer and allophanate groups, or a catalyst system comprising at least one catalyst capable of forming trimer groups and at least one catalyst capable of forming allophanate groups. This invention also relates to novel freeze-stable blends of the allophanate-modified toluene diisocyanurates with di- and/or polyisocyanates of the diphenylmethane series; and to freeze-stable urethane prepolymers of the allophanate-modified toluene diisocyanurates, or the blends of these with an isocyanate of the diphenylmethane series.

Abstract: Increases in reactivity of acidic containing RIM systems are reduced by inclusion of a catalyst system of a zinc-containing compound, a non-zinc containing metal compound and a tertiary amine.

Abstract: The present invention relates to highly elastic polyurethane contact adhesives, a process to coat substrates with these contact adhesives, and the coated substrates produced by this process. This invention requires a) a polyisocyanate with a functionality of less than about 4 and b) a polyol blend comprising 1) about 90 to 100% polyethers with molecular weights from about 1,800 to 12,000 and average functionality from about 1.5 to about 4, and 2) up to about 10% of chain extenders with molecular weights from about 60 to 400 and average functionality from about 1.5 to about 3. The functionalities and amounts of components a) and b) are such that the molecular weight between crosslinks is from about 7,000 to about 16,000 and the equivalent ratio of isocyanate groups to isocyanate-reactive groups is from about 80:100 to about 120:100 and the urethane group content is from about 1 to about 8%. It is preferred that at least one of components a) and b) have a functionality of greater than about 2.2.

Abstract: This invention relates to stable aromatic amine compositions. These compositions comprise a) an organic compound containing at least one carboxylic acid group, and b) an aromatic amine. This invention also relates to a process for stabilizing the color of aromatic amines, and to the use of these aromatic amines as initiators for the preparation of polyether polyols.

Abstract: This invention relates to a novel freeze-stable allophanate modified toluene diisocyanurates, and to a process for producing these freeze-stable allophanate-modified toluene diisocyanurates which requires a catalyst which is capable of forming both trimer and allophanate groups, or a catalyst system comprising at least one catalyst capable of forming trimer groups and at least one catalyst capable of forming allophanate groups. This invention also relates to novel freeze-stable blends of the allophanate-modified toluene diisocyanurates with di- and/or polyisocyanates of the diphenylmethane series; and to freeze-stable urethane prepolymers of the allophanate-modified toluene diisocyanurates, or the blends of these with an isocyanate of the diphenylmethane series.

Abstract: This invention relates to novel polyether polyols and to a process for their production. These polyether polyols are prepared by forming a polyhydroxyl group containing component in a first step by the reaction of a triazole-group containing compound with a compound that contains at least one functional group that is capable of reacting with the amine groups of the triazole group containing compound, and reacting the hydroxyl-group containing component with an alkylene oxide to form the polyether polyol of the invention. The present invention also relates to isocyanate-reactive compositions comprising these novel polyether polyols, and to a process for the production of a polyurethane comprising reacting a polyisocyanate with the novel polyether polyols of the present invention.

Abstract: The present invention relates to a novel process for the production of delayed action tin catalysts. This process comprises reacting a dialkyltin dihalide with an alkali metal sulfide, to yield the corresponding 2,2,4,4-tetrakis(alkyl)-1,3,2,4-dithia-stannetane catalyst.

Abstract: This invention relates to stable aromatic amine compositions. These compositions comprise a) a compound selected from the group consisting of alkali metal salts of sulfur compounds, hydrates thereof and aldehydes thereof, aluminum hydrides, borates and boron compounds; and b) an aromatic amine. This invention also relates to a process for stabilizing the color of aromatic amines, and to the production of polyether polyols from these stable aromatic amine compositions.