Abstract: Described herein is a compact polyurethane having a density of ?850 g/l, obtainable by reacting at least the components: i) a polyisocyanate composition; and ii) a polyol composition, including at least one polyether polyol (ii.1) which is obtainable by reacting ii.1.1) a polyol starter with a functionality of 3 to 6 with ii.1.2) propylene oxide and/or butylene oxide, in the presence of a boron-based, fluorine-containing Lewis acid catalyst (ii.1.3), where the polyether polyol (ii.1) has an equivalent molecular weight of 50 to 150 g/mol, and ii.1.4) optionally further auxiliaries and/or additives. Also described herein are a process for producing such a compact polyurethane and compact polyurethanes obtainable by this process. Also described herein is a method of using such a compact polyurethane for the production of a fiber composite. Also described herein are a corresponding fiber composite material and a process for producing such a fiber composite.

Abstract: New shape memory polymer compositions, methods for synthesizing new shape memory polymers, and apparatus comprising an actuator and a shape memory polymer wherein the shape memory polymer comprises at least a portion of the actuator. A shape memory polymer comprising a polymer composition which physically forms a network structure wherein the polymer composition has shape-memory behavior and can be formed into a permanent primary shape, re-formed into a stable secondary shape, and controllably actuated to recover the permanent primary shape. Polymers have optimal aliphatic network structures due to minimization of dangling chains by using monomers that are symmetrical and that have matching amine and hydroxl groups providing polymers and polymer foams with clarity, tight (narrow temperature range) single transitions, and high shape recovery and recovery force that are especially useful for implanting in the human body.

Abstract: A process for producing viscoelastic flexible polyurethane foams by reacting a) polyisocyanates with b) compounds having at least two hydrogen atoms which are reactive toward isocyanate groups, c) blowing agents, wherein b) comprise b1) from 70 to 10 parts by weight of at least one polyether alcohol having polyoxypropylene units, a nominal functionality of from 3 to 6 and a hydroxyl number of 100 to 300 mg KOH/g, b2) from 10 to 70 parts by weight of at least one polyetherol having polyoxypropylene units, a nominal functionality of 2 and a hydroxyl number of 50 to 350 mg KOH/g, b3) from 10 to 30 parts by weight of at least one polyether alcohol having ethylene oxide units, a nominal functionality of from 2 to 3 and a hydroxyl number of 50 to 550 mg KOH/g, b4) from 0 to 20 parts by weight of at least one graft polyetherol having a nominal functionality of from 2 to 3 and a hydroxyl number of 20 to 40 mg KOH/g.

Abstract: A cylindrical molding based on cellular polyurethane elastomers having a density according to DIN EN ISO 845 of from 300 to 900 kg/m3, a tensile strength according to DIN EN ISO 1798 of ?2.

Abstract: The present invention provides a process for conditioning double metal cyanide (DMC) catalysts, which are employed in the preparation of polyether polyols based on starter compounds having active hydrogen atoms, the preparation of polyether polyols using the conditioned catalysts and the use of the polyether polyols prepared in this way for the preparation of polyurethane materials.

Abstract: A polyisocyanate-based elastomer having a ratio of the storage modulus (E?) at 20° C. and the storage modulus (E?) at 120° C. of between 0.75 and 1.5, a tan ? at 100° C. of less than 0.1 and a maximum value of the tan ? of more than 0.8, the tan ? being the ratio of the loss modulus (E?) and the storage modulus (E?).

Abstract: Viscoelastic foams and elastomers based on a reaction system comprising a monomeric polyisocyanate composition, a specified mixture of polyols, and a specified package of additives. The viscoelastic materials offer superior combinations of physical properties, including surprisingly low compression sets. Very soft viscoelastic foams and microcellular elastomers can be conveniently prepared from the reaction system without the necessity of using plasticizers. The reaction system can be processed into useful polymeric articles using a wide range of conventional polyurethane processing methods.

Abstract: The soil mulching process, includes the following stages: mixing together at least two liquid starting substances able to react together to give rise, within a determined time period, to an inert solid final substance while still in the liquid state, pouring the obtained mixture onto the soil surface in a quantity such as to obtain on the soil surface, when the reaction between the components is complete, a layer of the solid substance of a thickness which prevents light passage through it.

Abstract: Process for preparing a polyurethane elastomer having an apparent overall density of more than 150 kg/m3 comprising reacting a polyisocyanate and an isocyanate-reactive composition, optionally in the presence of water, wherein the reaction is conducted at an isocyanate index of 85 to 120, the polyisocyanate comprising: a) 80-100% by weight of a diphenylmethane diisocyanate comprising at least 40% by weight of 4,4?-diphenylmethane diisocyanate and/or a derivative of said diphenylmethane diisocyanate which derivative is liquid at 25° C.

Abstract: A method of producing a heat insulating board comprising two opposed facings and a core made of a rigid synthetic resin foam, which comprises spraying or injecting a foam mix for the rigid synthetic resin foam into the space between the opposed face materials and expanding and curing the foam mix, wherein the foam mix comprises a particular polyol, a polyisocyanate, a foam stabilizer, a catalyst and a blowing agent, wherein the polyol contains a polyether polyol having a hydroxyl value of at most 84 mgKOH/g and an oxyethylene group content of at least 40 wt %; a polyether polyol which is obtained by adding a cyclic ether to an amine compound and has a hydroxyl value of from 250 to 900 mgKOH/g; and fine polymer particles stably dispersed in the polyol.

Abstract: Polyetherols based on solid initiator substances and liquid, hydroxyl-containing coinitiators are prepared by a catalyzed addition reaction of alkylene oxides by a process in which the initiator combination contains diols carrying ethoxy structures, the ratio of the average number of hydroxyl groups per mole of initiator combination to the number of ethoxy structures in the polyetherol being from 1:0.2 to 1:1.8 and the ratio of the amounts by weight of the diols carrying ethoxy structures to the average molecular weight of the polyetherol being from 1:2 to 1:15. The polyetherols prepared by this process are used for the preparation of PUR, in particular, rigid PUR foams.

Abstract: A flexible, latex-like polyurethane foam having the “feel” and comfort of a latex foam and an Indentation Force Deflection (25% IFD as low as 3 lbs.) and the method of making such foam by reacting a mixture of triol polyether polyols, namely, a) a major proportion of a triol polyol having a hydroxyl content of about 50-80%, a 10-25% ethylene oxide cap and a molecular weight of about 3,000-6,500, (b) a minor proportion of a polymer triol polyol, preferably SAN polyol, having a molecular weight of about 3,000-6,5000; and (c) a very minor amount of a triol polyol having a primary hydroxyl content of at least 50% and about 40-90% ethylene oxide cap and a molecular weight of from 1,000-6,000. The polyol mixture is reacted with a MDI isocyanate in the presence of a critical amount of from about 1.5 to about 3.5 parts by weight of water, an auxiliary blowing agent and an amine catalyst.

Abstract: The invention relates to a viscoelastic damping foam with an adhesive surface for adhesion coupling to vibrating surfaces, for solid-borne sound absorption. The viscoelastic damping foam is obtained through the stoichiometric reaction of a polyisocyanate with at least two polyols of the polyether type which are incompatible with one another.

Abstract: In a process for producing sound-absorbing PUR foams having an adhesive surface by reacting organic and/or modified organic polyisocyanates (a) with a polyetherol mixture (b) and, if desired, further compounds (c) bearing hydrogen atoms which are reactive toward isocyanates, in the presence of water and/or other blowing agents (d), catalysts (e) and, if desired, further auxiliaries and additives (f), the polyetherol mixture (b) comprises b1) at least one bifunctional to eight-functional polyetherol based on ethylene oxide and propylene oxide and having an OH number of from 20 to 80 mg KOH/g and a proportion of primary OH groups of >50%, b2) at least one polyetherol based on ethylene oxide and propylene oxide and/or butylene oxide and a bifunctional to eight-functional initiator and having an OH number of from 20 to 80 mg KOH/g, where the proportion of ethylene oxide in the polyetherol is >30% by weight, in amounts of from 10 to 50 parts by weight, and b3) at least one polyetherol based on propylene o

Abstract: Process for preparing a flexible polyurethane foam by reacting a polyisocyanate and two different polyols under foam forming conditions so as to prepare a rigid foam and by crushing the rigid foam so obtained. Flexible foams are obtained which do not show a major glass transition temperature between −100° C. and +25° C.

Abstract: A wound dressing has a wound-contact layer formed from a polyurethane foam. The foam comprises one part by weight of the reaction product of an isocyanate-capped prepolymer with water (and optionally other hydroxy-functional compounds), and from 0.03 to 0.3 parts by weight of a natural or synthetic rubber. The isocyanate-capped prepolymer is preferably an isocyanate-capped ethyleneoxy/propyleneoxy copolymer, and the rubber is preferably an acrylic rubber.

Abstract: Sound-damping and energy-absorbing flexible PUR foams are produced by reacting organic and/or modified organic polyisocyanates (a) with a polyetherol mixture (b) and, if desired, further compounds (c) bearing hydrogen atoms which are reactive toward isocyanates, in the presence of water and/or other blowing agents (d), catalysts (e) and, if desired, further auxiliaries and additives (f).

Abstract: Process for preparing a flexible foam by reacting a polyisocyanate having a high 4,4′-MDI content and a polyol having a high EO content in the presence of a foaming agent.

Abstract: The present invention discloses a method for the formation of and a flexible slabstock polyurethane foam having substantially improved indentation force deflection and resilience characteristics while maintaining the other physical properties. The method comprises the steps of: forming a polyol blend having a nominal functionality of at least 2.3 by combining at least one polyether polyol having a plurality of terminal ethylene oxide caps of from 5 to 25% by weight based on the total weight of the polyether polyol, a molecular weight of greater than or equal to 4000 Daltons, and an unsaturation of greater than 0.04 meq/g KOH; at least one graft polyether polyol having an equivalent weight of greater than 1000 Daltons, a solids content of at least 28%, and a plurality of terminal ethylene oxide caps of from 5 to 25% by weight based on the total weight of the graft polyether polyol; and at least one very low unsaturated polyether polyol having an unsaturation of less than or equal to 0.

Abstract: Process for making flexible polyurethane foams using MDI and TDI and a polyol composition comprising dispersed particulate material.

Abstract: This invention relates to a process for the production of resilient, flexible polyurethane foams. This process comprises reactingA) polyisocyanates or polyisocyanate prepolymers,B) compounds having at least two isocyanate-reactive hydrogen atoms and a molecular weight of 500 to 18000,C) optionally, compounds having at least two isocyanate-reactive hydrogen atoms and a molecular weight from 32 to 499,D) water,E) optionally, blowing agents,F) activators, stabilizers and other per se known additives, andG) one or more crosslinking agents,wherein component B) comprisesB)i) at least one polyether polyol having of a functionality of 4 to 8 preferably of 4.5 to 8, more preferably of 5 to 7, andB)ii) at least one polyol containing a filler from the group of PUD-, SAN- or PIPA-modified polyols of a functionality of 2.

Abstract: In a process for producing flexible polyurethane foams by reactinga) organic and/or modified organic polyisocyanates withb) relatively high molecular weight compounds containing at least two reactive hydrogen atoms andc) if desired, low molecular weight chain extenders and/or cross linkersin the presence ofd) blowing agents,e) catalysts,f) flame retardants and, if desiredg) further auxiliaries and/or additives,the relatively high molecular weight compounds containing at least two reactive hydrogen atoms (b) comprise at least 10% by weight of polyether polyols which can be prepared by base-catalyzed reaction of lower alkylene oxides with OH-functional initiator substances and are subjected, during or after the molecular addition of alkylene oxide, to a combined thermal/distillative treatment at a water content of at most 0.1% by weight.The flexible PUR foam produced according to the present invention can be used in the automobile and furniture sectors and for producing flexible foam/textile composites.

Abstract: This invention relates to molded articles comprising micro cellular polyurethane foams, preferably integral skin foams. These exhibit improved properties and are particularly suitable for soling systems in footwear. The present invention also relates to a process for the production of these molded articles. These molded articles comprise the reaction product of (A) an isocyanate comprising a stable, liquid MDI based prepolymer containing an allophanate-modified MDI, with (B) an isocyanate reactive component, in the presence of (C) at least one blowing agent.

Abstract: Process for the production of flexible polyurethane foams by reactingA) polyisocyanates or polyisocyanate prepolymers, withB) a specific blend of isocyanate-reactive compounds,C) water,D) optionally, blowing agents,E) optionally, activators, stabilizers and other per se known additives.The specific blend of isocyanate-reactive compounds B) comprises:i) at least one polyether polyol of a functionality of more than 2.5 to 6.0,ii) at least one polyether polyol of a functionality of 1.8 to less than 2.5,iii) at least one polyether polyol of a functionality of 1.8 to 6.0 having an EO content in the polyether chain of at least 50 wt. %.The flexible foams produced according to the present invention are characterized by moderate compressive strength at an elevated bulk density.

Abstract: Microcellular polyurethane elastomer shoe sole components have exceptional physical properties may be prepared from isocyanate-terminated prepolymers derived from polyoxypropylene diols having a molecular weight of from about 2000 Da to 8000 Da, an unsaturation less than about 0.02 meq/g, and a random oxyethylene content of from about 5 to about 15 weight percent. The shoe sole components exhibit high tensile strength, elongation, resilience, and in addition have excellent tear strength, particularly 90.degree. angle tear.

Abstract: Process for the production of flexible polyurethane foams by reactingA) polyisocyanates or polyisocyanate prepolymers, withB) a specific blend of isocyanate-reactive compounds,C) water,D) optionally, blowing agents,E) optionally, activators, stabilizers and other per se known additives.The specific blend of isocyanate-reactive compounds B) comprises:i) at least one polyether polyol of a functionality of more than 2.5 to 6.0,ii) at least one polyether polyol of a functionality of 1.8 to less than 2.5,iii) at least one polyether polyol of a functionality of 1.8 to 6.0 having an EO content in the polyether chain of at least 50 wt. %.The flexible foams produced according to the present invention are characterized by moderate compressive strength at an elevated bulk density.

Abstract: Isocyanate-terminated-prepolymers prepared from polyoxyalkylene polyether polyols having low unsaturation are suitable for producing polyurethane molded foam having exceptional physical properties. Preferably, the foams are all water blown, and process well. The foams are noted for concomitant increases in both tensile strength and elongation as well as displaying excellent wet set and other properties.

Abstract: Disclosed is a water blown, open cell, hydrophilic polyurethane foam, a process for preparing such a foam and articles made therefrom. Utilizing a one step process the foam is formed from a reaction mixture comprising an organic polyisocyanate, water, a reaction catalyst and a mixture of certain polyols. The first polyol utilized in the invention is a poly(oxyalkylene) triol, chain terminated with propylene oxide and having a molecular weight in the range of about 2800 to about 6200. The second polyol is a poly(oxyalkylene) polyol, chain terminated with ethylene oxide or propylene oxide and having a molecular weight in the range of about 60 to about 800. The third polyol comprises at least one selected from the group of (i) poly(oxyalkylene) diols chain terminated with ethylene oxide and having a molecular weight in the range of about 500 to about 4000 and (ii) polyfunctional polyols chain terminated with propylene oxide and having a molecular weight in the range of about 250 to about 1000.

Abstract: Polyurethane elastomers exhibiting improved green strength while maintaining short demold times are prepared from ultra-low unsaturation polyoxypropylene polyols containing up to 20 weight percent internal random oxyethylene moieties. The elastomers adsorb less than 10 weight percent water at 0.degree. C. The internal polyoxyethylene moiety-containing polyoxypropylene polyols may be used to prepare ultra-low unsaturation polyoxyethylene capped polyols which are haze-free and which may be used to prepare haze-free 4,4'-MDI prepolymers. Multidisperse blends of monodisperse internal oxyethylene moiety-containing polyoxypropylene polyols of ultra-low unsaturation provide yet further improvements in elastomer processing.

Abstract: Polyoxyalkylene polyether polyols suitable for preparation of flexible polyurethane foams are prepared by oxyalkylating an aqueous solution of one or more polyhydric, hydroxyl-functional solid initiators under conditions where both water as well as initiator are oxyalkylated. The polyols have calculated functionalities of between about 2.2 and 4.0 and hydroxyl numbers in the range of 10 to 180. The polyols may be used to prepare soft, high resiliency polyurethane flexible foams at low isocyanate indexes.

Abstract: Hydrophilic polyurethane foams with rapid wet out properties are formed from the reaction product of an MDI-based or polymeric MDI-based isocyanate capped prepolymer with an aqueous component, such as water, and about 0.5 to 2.0 parts by weight, based on 100 parts by weight prepolymer, of a silicone glycol copolymer liquid surfactant with a polyether portion, said surfactant having a viscosity of about 175 to 350 CST at 25.degree. C., a molecular weight in the range of about 1500 to 20,000, with the polyether portion having a molecular weight in the range of about 200 to 2000 and containing about 40 to 100 percent by weight ethylene oxide. The surface of the hydrophilic foam wets out or absorbs droplets of water in less than thirty (30) seconds, preferably instantaneously (less than one second).

Abstract: For the expansion of a liquid containing gas under pressure in dissolved form, it is proposed that the liquid be passed with expansion through an extended flow channel with a small cross-sectional measurement with generation of high rates of shear. The velocity of the liquid is then reduced prior to the foaming.

Abstract: The invention relates to pressurized, blowing-agent-containing isocyanate semiprepolymer mixtures, advantageously having an isocyanate content of from 5 to 25% by weight, based on organic polyisocyanates and polyhydroxyl compounds which are used in combination with a linear, branched or cyclic, saturated or olefinically unsaturated monoalcohol having 1 to 25 carbon atoms and/or hydroxyketones, preferably .beta.-hydroxyketones, the use thereof for the production of one-component polyurethane foams by allowing the isocyanate semiprepolymer mixtures to depressurize, and a process therefor.

Abstract: The present invention to water-blown integral skin polyurethane foam compositions, molded polyurethane articles, a process of preparing said articles, and an isocyanate composition for use therein. In particular, the invention relates to water-blown integral skin molded polyurethane articles having particularly advantageous physical properties, and compositions useful for producing such articles.In particular, the invention provides a polyurethane composition which has an isocyanate component (a) an isocyanate reactive component (b), a blowing agent comprising water (c), a polyether (d) selected from the group consisting of polytetrahydrofuran and polyethylene glycol having a number average molecular weight of from 200 to 2000 and optionally, one or more additives (e) from the group consisting of catalysts, chain extenders, oxo alcohols, and mixtures thereof.

Abstract: Polyether polyol comprising as alkylene oxide units ethylene oxide and propylene oxide units, said polyol having a nominal average hydroxyl functionality of 2-6, an hydroxyl value of 16-45 mg KOH/g, a primary hydroxyl content of at least 50% calculated on the total amount of hydroxyl groups and an amount of ethylene oxide units, calculated on the weight of the alkylene oxide units in the polyol, of 21-49% by weight these polyols are useful for making flexible foam.

Abstract: Polyether polyol comprising as alkylene oxide units ethylene oxide and propylene oxide units, said polyol having a nominal average hydroxyl functionality of 2-6, an hydroxyl value of 16-45 mg KOH/g, a primary hydroxyl content of at least 50% calculated on the total amount of hydroxyl groups and an amount of ethylene oxide units, calculated on the weight of the alkylene oxide units in the polyol, of 21-49% by weight. These polyols are useful for making flexible foam.

Abstract: Method for preparation of fluorochlorohydrocarbon-free (FCHC-free) low-density polyurethane soft-foam materials and soft-elastic polyurethane soft-foam materials as well as polyisocyanate mixtures modified with urethane groups, and based on diphenylmethane-diisocyanate, which are applicable thereto.

Abstract: Polyol composition comprising a polyol having a high functionality and a high ethylene oxide content and another polyol. Process for preparing a flexible foam from such polyols.

Abstract: A method for the preparation of flexible polyurethane foams by reacting a polyisocyanate containing at least 85% by weight of 4,4'-diphenylmethane diisocyanate or a liquid variant thereof with a polyol composition comprising at least one poly(oxyethylene-oxyalkylene) polyol, the composition having an average nominal hydroxyl functionality of from 2.5 to 6, a number average hydroxyl equivalent weight of from 1000 to 3000 and an average oxyethylene content of from 25 to less than 50% by weight and with water.

Abstract: Isocyanate-based foams are produced by the reaction of polyisocyanates with compounds with molecular weights of from 400 to 10,000 and having at least two hydrogen atoms active towards isocyanates in the presence of hydrocarbons which are vaporizable under the foaming conditions as blowing agents. The active hydrogen component is a mixture of a) one or more nitrogen-free polyethers having at least two hydrogen atoms active towards isocyanates and containing oxyethylene residues, and b) one or more polyethers having at least two hydrogen atoms active towards isocyanates and containing no oxyethylene groups.

Abstract: The present invention relates to a process for the preparation of flexible, soft polyurethane foams having viscoelastic, structure-borne soundproofing properties in a temperature range of from -20.degree. C. to +80.degree. C. by reactinga) a polyoxyalkylene-polyol mixture containingai) block polyoxypropylene-polyoxyethylene-polyol mixture having a hydroxyl number of from 14 to 65 and containing from 2 to 9% by weight of terminal ethylene oxide units, based on the weight of the polyoxypropylene units, prepared by anionic polymerization, at elevated temperatures, of 1,2-propyleneoxide onto an initiator molecule mixture having a mean functionality of from 2.3 to 2.

Abstract: A method for the preparation of shape memory polyurethane foams by reacting a polyisocyanate component and a polyol composition in the presence of a foaming agent comprising water wherein the polyisocyanate component contains at least 85% by weight of 4,4'-diphenylmethane diisocyanate or a variant thereof and the polyol composition comprises at least one polyoxyalkylene polyol containing oxyethylene residues, said polyol composition having an average nominal hydroxyl functionality of from 2.2 to 6, an average oxyethylene content of at least 86% by weight and an average hydroxyl equivalent weight from 250 to 1500.

Abstract: The invention relates to a polyether polyol, a water-curable polyurethane prepolymer prepared by using the polyether polyol, and a composition containing the prepolymer. The above polyether polyol is obtainable by subjecting an active hydrogen compound to addition polymerization reaction with ethylene oxide and an alkylene oxide of 3 to 4 carbon atoms in a specified ratio. The above water-curable polyurethane prepolymer is obtainable by reacting the polyether polyol with a polyisocyanate compound. The above composition comprises a mixture of the water-curable polyurethane prepolymer and the polyisocyanate. The above water-curable polyurethane prepolymer and composition provide a foam of fine and uniform cell structure with improved strength on curing with water.

Abstract: Flexible polyurethane foams having densities lower than 25 kg/m.sup.3 and a load bearing capacity, at a 40% compression, higher than 150N, prepared by reacting a modified polyiso=cyanate with a compound containing active end hydrogens and wherein high levels of water are used as foaming agent, without risk of self-ignition.

Abstract: The invention provides a method for the preparation of fluorochlorohydrocarbon(FCHC)-free polyurethane soft (molded) foam materials with low density, by reactingA) liquid polyisocyanate mixtures containing bound urethane groups, containing 22 to 30 weight percent of NCO groups, which in turn are prepared by reacting a mixture of diphenylmethane-diisocyanate and polyphenyl-polymethylene-polyisocyanates (raw MDI) with at least one polyoxypropylene-polyoxyethylene-polyol with a functionality between 2.5 and 3.

Abstract: The present invention is directed to a process for the preparation of molded cold-cure polyurethane flexible foams. The process requires the use of aromatic polyisocyanates, a specifed mixture of polyether polyols which have specified ethylene oxide contents and a specified amount of water as blowing agent. The reaction is conducted in a closed mold at an isocyanate index of from 80 to 120.

Abstract: The invention relates to polyol components, in particular for reaction with polyisocyanates of the diphenylmethane series, which comprisea) a polyol having a hydroxyl equivalent weight of up to 150 and a functionality of 4 to 8,b) a polyether-polyol having a hydroxyl equivalent weight of more than 1900 and a functionality of 2 to 4 andc) a polypropylene glycol having a functionality of 2 to 3, a polytetrahydrofuran, each of which has a hydroxyl equivalent weight of 150 to 500, or a mixture of the two. The polyol components are distinguished by a low tendency to demix, even during prolonged storage. Reaction mixtures of the polyol components described and polyisocyanates of the diphenylmethane series cure fully without passing through a brittle phase. The mouldings formed have good mechanical properties.

Abstract: A polyurethane adhesive is prepared from a reaction mixture containing small amounts of chain extender material and a high equivalent weight of a polyol and a monoalcohol. An article adhered to a substrate using this adhesive is firmly affixed to the substrate, yet can be removed without leaving residual adhesive on the substrate. In addition, this adhesive can be washed and reused if desired.

Abstract: The flame retardancy of flexible polyurethane foams is increased by incorporation into the foam forming reactants of a low molecular weight, high primary hydroxyl trifunctional polyether polyol having a hydroxyl number between 300 and 500 and a primary hydroxyl content greater than 50 percent.

Abstract: This invention relates to elastomeric polyisocyanate-based polymers, particularly polyurethane elastomeric polymers, prepared from polyol compositions comprising a polyoxyalkylene polyol having a hydroxyl equivalent weight of from about 800 to about 3000 and containing from 10 to 40 weight percent polymerized ethylene oxide wherein the ethylene oxide is distributed as a plurality of internal polyoxyethylene blocks having a molecular weight of from about 176 to about 600, and a polyoxyethylene cap use of such polyols. Polyols provides for polymers exhibiting desirable physical properties including good abrasion wear resistance.