Abstract: A polyurethane-forming reaction mixture characterized by its ability to be adjusted with respect to its viscosity in response to changing temperature and humidity conditions is achieved with a mixture that includes a liquid polyisocyanate having an isocyanate group content of at least 10% by weight, an isocyanate-reactive component which includes at least one high molecular weight polyol, a urethane catalyst and from 0.2 to 5 parts by weight per 100 parts by weight of isocyanate reactive component of a viscosity adjusting component. The viscosity adjusting component is preferably a diamine, a polyamine and/or an amine-terminated polyol. This reaction mixture is particularly useful for producing polyurethane geotextile composite materials useful as liners for ditches and canals.

Abstract: Seams are sealed and surface defects are repaired in a polyurethane/geotextile composite applied over concrete, an earthen canal or a ditch with a non-sagging polyurethane composition. This non-sagging polyurethane composition is a reaction product of a polyisocyanate, a high molecular weight polyhydroxyl compound, and a compound containing at least two amino groups. A low molecular weight diol or triol, a catalyst and a filler are optionally included in the polyurethane-forming reaction mixture.

Abstract: A polyurethane-forming reaction mixture characterized by its ability to be adjusted with respect to its viscosity in response to changing temperature and humidity conditions is achieved with a mixture that includes a liquid polyisocyanate having an isocyanate group content of at least 10% by weight, an isocyanate-reactive component which includes at least one high molecular weight polyol, a urethane catalyst and from 0.2 to 5 parts by weight per 100 parts by weight of isocyanate reactive component of a viscosity adjusting component. The viscosity adjusting component is preferably a diamine, a polyamine and/or an amine-terminated polyol. This reaction mixture is particularly useful for producing polyurethane geotextile composite materials useful as liners for ditches and canals.

Abstract: This invention relates to syntactic foams comprising the reaction product of a liquid diphenylmethane diisocyanate component, with an isocyanate-reactive component, a filler having a density of less than 1 g/cm 3, and at least one organo-metallic catalyst. This invention also relates to the use of these syntactic foams for insulating pipes.

Abstract: A water-resistant polyurethane geotextile composite suitable for use as a liner is made by impregnating a geotextile with a water-resistant polyurethane and allowing the polyurethane impregnated in the geotextile to cure. The water-resistant polyurethane composition is a reaction product of (a) a liquid polyisocyanate having an isocyanate content of at least 10% by weight, (b) an isocyanate-reactive component which includes (1) 20-90% by weight castor oil having a water content of less than 0.5% by weight, and (2) a polyether polyol in which at least 70% by weight of the alkylene oxide is propylene oxide, and (c) a urethane catalyst. Low molecular weight diols and triols and fillers may optionally be included.

Abstract: This invention relates to syntactic foams comprising the reaction product of a liquid diphenylmethane diisocyanate component, with an isocyanate-reactive component, a filler having a density of less than 1 g/cm 3, and at least one organo-metallic catalyst. This invention also relates to the use of these syntactic foams for insulating pipes.

Abstract: An improved polyurethane/geotextile composite is prepared from a polyurethane forming composition in which a liquefied monomeric diphenylmethane diisocyanate (MDI) is used as the isocyanate component. Such composites may be used to line canals and/or ditches by applying the geotextile soaked with polyurethane forming composition to the surface to be lined before the polyurethane-forming reaction has been completed and allowing the polyurethane to cure in place. These composites are characterized by improved physical and mechanical properties and the ability to withstand dramatic changes in the temperature of the environment in which they are employed.

Abstract: A polyurethane-forming reaction mixture characterized by its ability to be adjusted with respect to its viscosity in response to changing temperature and humidity conditions is achieved with a mixture that includes a liquid polyisocyanate having an isocyanate group content of at least 10% by weight, an isocyanate-reactive component which includes at least one high molecular weight polyol, a urethane catalyst and from 0.2 to 5 parts by weight per 100 parts by weight of isocyanate reactive component of a viscosity adjusting component. The viscosity adjusting component is preferably a diamine, a polyamine and/or an amine-terminated polyol. This reaction mixture is particularly useful for producing polyurethane geotextile composite materials useful as liners for ditches and canals.

Abstract: This invention relates to fertilizer encapsulation with polyurethanes wherein the isocyanate-reactive composition contains sulfur. The process of the present invention comprises applying a polyisocyanate composition to fertilizer particles, applying an isocyanate-reactive composition which contains sulfur to the polyisocyanate coated fertilizer particles, or applying an isocyanate-reactive composition which contains sulfur to fertilizer particles and then applying a polyisocyanate composition to the isocyanate-reactive coated fertilizer particles, and repeating these steps as necessary to form sulfur containing polyurethane encapsulated fertilizer particles.

Abstract: A surface of a canal, ditch or pipe is lined with a polyurethane/geofabric composite. A non-sagging polyurethane composition is applied to the canal, ditch or pipe surface, a geofabric is contacted with that surface in a manner such that the geofabric becomes impregnated with the non-sagging polyurethane composition which cures to form a polyurethane/geofabric composite. The non-sagging polyurethane is a reaction product of a polyisocyanate, a high molecular weight polyhydroxyl compound and a compound having at least 2 amino groups. A low molecular weight diol or triol, filler and catalyst are optional components. These composites are particularly useful in lining cracked or broken concave or angled surfaces.

Abstract: The present invention is directed to a method for impregnating at least one geofabric with a liquid solidifiable polyurethane composition, conforming at least one polyurethane-impregnated geofabric to a surface (such as to the surface of a canal, ditch and/or pipe) and allowing the liquid solidifiable polyurethane composition to cure and form a polyurethane/geofabric composite. The liquid solidifiable polyurethane composition is the reaction product of COMPONENT A, COMPONENT B and COMPONENT C, as defined herein. COMPONENT C has the same equivalent weight as COMPONENT B and contains catalyst. One advantage of the present invention is that the ratio of COMPONENT B to COMPONENT C can be adjusted during processing without changing the isocyanate index. As a result, geltimes of liquid solidifiable polyurethane compositions of the present invention can be adjusted to accommodate changes in outdoor application temperature.

Abstract: This invention relates to fertilizer encapsulation with polyurethanes wherein the isocyanate-reactive composition contains sulfur. The process of the present invention comprises applying a polyisocyanate composition to fertilizer particles, applying an isocyanate-reactive composition which contains sulfur to the polyisocyanate coated fertilizer particles, or applying an isocyanate-reactive composition which contains sulfur to fertilizer particles and then applying a polyisocyanate composition to the isocyanate-reactive coated fertilizer particles, and repeating these steps as necessary to form sulfur containing polyurethane encapsulated fertilizer particles.

Abstract: This invention relates to a process for the production of an optically clear, light-stable polyurethane-urea elastomer having an onset softening point of at least 130° C., processed at ambient temperature and casted in a mold at an isocyanate index of 95 to 120. This process comprises reacting: A) a liquid polyisocyanate or polyisocyanate prepolymer having an NCO group content of about 5 to about 50%, an average functionality of 2 to 3, a viscosity of less than 5,000 mPa.s at 25° C.; and B) an isocyanate-reactive component; in the presence of C) at least one organometallic catalyst. The present invention also relates to the optically clear, light-stable polyurethane-urea elastomers produced by this process.

Abstract: A polyurethane-forming reaction mixture characterized by its ability to be adjusted with respect to its viscosity in response to changing temperature and humidity conditions is achieved with a mixture that includes a liquid polyisocyanate having an isocyanate group content of at least 10% by weight, an isocyanate-reactive component which includes at least one high molecular weight polyol, a urethane catalyst and from 0.2 to 5 parts by weight per 100 parts by weight of isocyanate reactive component of a viscosity adjusting component. The viscosity adjusting component is preferably a diamine, a polyamine and/or an amine-terminated polyol. This reaction mixture is particularly useful for producing polyurethane geotextile composite materials useful as liners for ditches and canals.

Abstract: This invention relates to a process for the preparation of polyurethane encapsulated fertilizer particles. This process comprises applying an isocyanate-reactive component to fertilizer particles, and applying an aliphatic polyisocyanate to fertilizer particles in separate steps to form polyurethane encapsulated fertilizer particles. The two reactants may be applied in either order, with the polyisocyanate being first or last. These two steps may optionally be repeated as many times, as necessary to yield polyurethane encapsulated fertilizer particles which contain from 0.5 to 15% by weight of polyurethane, based on the total weight of the encapsulated fertilizer particles. It is also possible to mix the isocyanate-reactive component and the polyisocyanate together to form a mixture which is then applied to the fertilizer particles. These polyurethane coatings which encapsulates the fertilizer particles are biodegradable.

Abstract: This invention relates to novel liquid, polyurethane plasticizers which contain less than 13% by weight, preferably less than 6% by weight of allophanate groups, carbodiimide groups, and/or uretonimine groups, and to a process for the preparation of these liquid polyurethane plasticizers.

Abstract: Seams are sealed and surface defects are repaired in a polyurethane/geotextile composite applied over concrete, an earthen canal or a ditch with a non-sagging polyurethane composition. This non-sagging polyurethane composition is a reaction product of a polyisocyanate, a high molecular weight polyhydroxyl compound, and a compound containing at least two amino groups. A low molecular weight diol or triol, a catalyst and a filler are optionally included in the polyurethane-forming reaction mixture.

Abstract: A surface of a canal, ditch or pipe is lined with a polyurethane/geofabric composite. A non-sagging polyurethane composition is applied to the canal, ditch or pipe surface, a geofabric is contacted with that surface in a manner such that the geofabric becomes impregnated with the non-sagging polyurethane composition which cures to form a polyurethane/geofabric composite. The non-sagging polyurethane is a reaction product of a polyisocyanate, a high molecular weight polyhydroxyl compound and a compound having at least 2 amino groups. A low molecular weight diol or triol, filler and catalyst are optional components. These composites are particularly useful in lining cracked or broken concave or angled surfaces.

Abstract: A water-resistant polyurethane geotextile composite suitable for use as a liner is made by impregnating a geotextile with a water-resistant polyurethane and allowing the polyurethane impregnated in the geotextile to cure. The water-resistant polyurethane composition is a reaction product of (a) a liquid polyisocyanate having an isocyanate content of at least 10% by weight, (b) an isocyanate-reactive component which includes (1) 20-90% by weight castor oil having a water content of less than 0.5% by weight, and (2) a polyether polyol in which at least 70% by weight of the alkylene oxide is propylene oxide, and (c) a urethane catalyst. Low molecular weight diols and triols and fillers may optionally be included.

Abstract: This invention relates to liquid polyisocyanate compositions having improved freeze stability. These liquid polyisocyanate compositions have an NCO group content of 15 to 30%, and comprise (A) an allophanate-modified MDI and having an NCO group content of 16 to 32.5%, (B) a low molecular weight branched aliphatic dihydroxy compound, and (C) an epoxide functional compound which is present in an amount of 0.01 to 1% by weight, based on the combined weight of components (A) and (B).