N=c=x Reactant Having At Least Two C-nh-c(=x)- Groups, E.g., Prepolymers, Etc. Patents (Class 521/159)
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Patent number: 4190712Abstract: An impact energy-absorbing, low density urethane foam for use in automobile bumpers has good moldability and is relatively temperature insensitive, i.e. gives approximately the same physical performance over a wide range of temperatures. This foam is characterized by its good multiple impact performance and low compression set values. The foam is water blown in a closed mold from a quasi-prepolymer system. The molded density is preferably in the range of 5 to 10 PCF.The foam formulation is based on a polymer polyol of a poly (oxypropylene/ethylene) triol reacted with a styrene/acrylonitrile monomer mixture which triol thus modified is reacted with (1) a roughly 1/5 to 1.5/1 weight amount of a hydroxy terminated polybutadiene homopolymer based on polymer polyol, (2) a 50 to 150 equivalent weight polyol crosslinker of 2 to 6 functionality, (3) a MDI glycol or triol quasi-prepolymer, and (4) some water.Type: GrantFiled: August 25, 1978Date of Patent: February 26, 1980Assignee: McCord CorporationInventor: Kirby E. L. Flanagan
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Patent number: 4189542Abstract: The instant invention is directed to a process for the production of weather-resistant rigid molded foams based on polyurethanes having a dimensional stability under heat according to DIN 53 432 of at least 70.degree. C. and a compact surface, a cellular core and an integral density distribution throughout the cross-section of the moldings, comprising foaming a foamable reaction mixture of polyisocyanates, polyhydroxyl compounds, blowing agents and, optionally, other isocyanate-reactive compounds, activators and other auxiliaries in a closed mold under the conditions of in-mold foaming, the improvement wherein the polyisocyanates used are reaction products containing isocyanate groups and urethane groups, said reaction products formed by reacting diisocyanates containing at least one cycloaliphatically bound isocyanate group and no more than one aliphatically bound isocyanate group with sub-stoichiometric quantities of organic polyhydroxyl compounds.Type: GrantFiled: August 2, 1978Date of Patent: February 19, 1980Assignee: Bayer AktiengesellschaftInventors: Helmut Kleimann, Holger Meyborg, Hans-Jurgen Lienert, Gerhard Grogler
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Patent number: 4187357Abstract: An oxyalkylated product useful for making polyurethane foams is prepared by reacting an alkylene oxide with a heated mixture of a phenol and a non-phenolic active hydrogen compound, at least one of which can be halogenated, in the presence of a catalyst complex of a phenol and an iron or aluminum substance. The mixture can also include a neutral phosphorus compound and/or acid anhydrides to enhance flame retardant properties. Optionally, also, the oxyalkylation reaction can be terminated by adding a tri (lower alkyl) amine and alkylene oxide to react with residual phenolic hydrogen in the mixture.Type: GrantFiled: April 13, 1978Date of Patent: February 5, 1980Assignee: BASF Wyandotte CorporationInventors: Arthur L. Austin, William W. Levis, Jr., Louis C. Pizzini, Robert J. Hartman
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Patent number: 4186257Abstract: This invention relates to new high molecular weight polyurethanes which contain a very small amount of urethane and urea groups. These new synthetic resins are built up as block copolymers and contain relatively high molecular weight segments which are derived from high melting and low melting polyols and linked together through ester and/or urethane and/or urea groups.Type: GrantFiled: February 6, 1978Date of Patent: January 29, 1980Assignee: Bayer AktiengesellschaftInventors: Johannes Blahak, Roland Gipp, Kuno Wagner, Erwin Muller, Jan Mazanek, Peter Haas
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Patent number: 4184990Abstract: The instant invention relates to the preparation of stable, relatively low viscosity dispersions of polyisocyanate-polyaddition products in hydroxyl containing compounds as dispersing agents. The process broadly comprises mixing an aqueous dispersion of an isocyanate-polyaddition product with a compound having at least two hydroxyl groups and having a boiling point about 100.degree. C., and thereafter at least partially distilling off the water.Type: GrantFiled: November 10, 1976Date of Patent: January 22, 1980Assignee: Bayer AktiengesellschaftInventors: Artur Reischl, Armin Zenner
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Patent number: 4181770Abstract: A hydrophilic foam is produced by mixing an isocyanate terminated branched polyethylene polyol with a polyester prepolymer and water. The foam may be used to impregnate fabrics, e.g., non-wovens, to produce reinforced sheets of foam of high absorbency and markedly improved abrasion resistance. Preferred polyesters are condensation products of adipic acid plus one or more alkanediols or a polylactone. Other prepolymers may also be included in the mix undergoing foaming, along with conventional additives.Type: GrantFiled: November 25, 1975Date of Patent: January 1, 1980Assignee: Firma Carl FreudenbergInventors: Gunter Schuhmacher, Walter Fottinger, Adolf Graber, Erich Fahrbach
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Patent number: 4177335Abstract: An oxyalkylated product useful for making polyurethane foams is prepared by reacting an alkylene oxide with a heated mixture of a phenol and a non-phenolic active hydrogen compound, at least one of which can be halogenated, in the presence of a catalyst complex of a phenol and an iron or aluminum substance. The mixture can also include a neutral phosphorus compound and/or acid anhydrides to enhance flame retardant properties. Optionally, also, the oxyalkylation reaction can be terminated by adding a tri (lower alkyl) amine and alkylene oxide to react with residual phenolic hydrogen in the mixture.Type: GrantFiled: April 14, 1978Date of Patent: December 4, 1979Assignee: BASF Wyandotte CorporationInventors: Arthur L. Austin, William W. Levis, Jr., Louis C. Pizzini, Robert J. Hartman
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Patent number: 4174435Abstract: The present invention relates to new polyols modified by phosphonoformamidine groups, to a process for the preparation thereof and the use thereof as starting component for the preparation of preferably foamed polyurethane plastics.The process involves (A) reacting diisocyanatocarbodiimides corresponding to the following general formula:OCN--R.sup.2 --N.dbd.C.dbd.N).sub.m R.sup.2 --NCOwith polyhydroxyl compounds corresponding to the following general formula:A--OH).sub.nto form a polyhydroxyl compound containing carbodiimide groups and (B) reacting the carbodiimide groups remaining in the product of step (A) by means of a basic catalyst with a phosphite corresponding to the following general formula: ##STR1## to form phosphonoformamidine groups wherein m represents a number of from 1 to 10, andR.sup.1 represents a C.sub.1 -C.sub.18 aliphatic, C.sub.4 -C.sub.15 cycloaliphatic or C.sub.6 -C.sub.Type: GrantFiled: March 23, 1978Date of Patent: November 13, 1979Assignee: Bayer AktiengesellschaftInventors: Walter Schafer, Kuno Wagner, Kurt Findeisen
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Patent number: 4174433Abstract: This invention relates to new polyols modified by guanidine groups, to a process for the preparation thereof and to the use thereof as starting component for the preparation of preferably foamed polyurethane plastics. The process involves (A) reacting diisocyanato-carbodiimides corresponding to the following general formula:OCN--R.sup.2 -N.dbd.C.dbd.N).sub.m R.sup.2 -NCOat a temperature of from about 25.degree. to 130.degree. C., optionally in the presence of an inert solvent, with polyhydroxyl compounds corresponding to the following general formula:A--OH).sub.nin an ON/NCO-ratio of from 1.2:1 to 30:1 to form a polyhydroxyl compound containing carbodiimide groups and (B) completely or partly reacting, at a temperature of from 0.degree. to 150.degree. C., the remaining carbodiimide groups remaining in the production of Step (A), optionally in the presence of an inert solvent, with an amine, amide or hydrazide corresponding to the following general formula:R.sup.3 --NR.sup.1 H).sub.Type: GrantFiled: March 23, 1978Date of Patent: November 13, 1979Assignee: Bayer AktiengesellschaftInventors: Walter Schafer, Kuno Wagner, Kurt Findeisen
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Patent number: 4172936Abstract: This invention relates to new polyols modified by acyl urea groups, to a process for the preparation thereof and to the use thereof as starting component for the preparation of preferably foamed polyurethane plastics. The process involves (A) reacting diisocyanatocarbodiimides corresponding to the following general formula:OCN--R.sup.2 --N.dbd.C.dbd.N).sub.m R.sup.2 --NCOat a temperature of from about 25.degree. to 130.degree. C., optionally in the presence of an inert solvent, with polyhydroxyl compounds corresponding to the following general formula:A--OH).sub.nin an OH/NCO-ratio of from 1.2:1 to 30:1 to form a polyhydroxyl compound containing carbodiimide groups and (B) completely or partially reacting, the carbodiimide groups remaining in the product of step (A) at a temperature of from 25.degree. to 100.degree. C.Type: GrantFiled: March 23, 1978Date of Patent: October 30, 1979Assignee: Bayer AktiengesellschaftInventors: Walter Schafer, Kuno Wagner, Kurt Findeisen
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Patent number: 4171390Abstract: A process of producing a porous polyurethane resin filter material. A first solution containing an NCO-adduct dissolved in a highly polar organic solvent is admixed into a second solution containing a highly polar organic solvent and at least one hydrazine hydrate, carbodihydrazide, piperazine and 1,4-diaminopiperazine. The first solution is admixed into the second solution over an extended period of time during which time the viscosity of the admixture is monitored and during which time the NCO pre-adduct and the hydrazine (or the like) react to form a polyurethane reaction product. During this time, the viscosity of the admixture increases. Admixture is continued with monitoring of the viscosity of the admixture until a point is reached at which the addition of even the minutest amount of the first solution into the admixture would result in instantaneous gelling thereof. At this point, the solids content of the final admixture is between 15 and 35% by weight.Type: GrantFiled: May 17, 1978Date of Patent: October 16, 1979Assignees: Chemie-Anlagenbau Bischofsheim GmbH, Reuter Technologie GmbHInventors: Karl Hilterhaus, Franz G. Reuter
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Patent number: 4165414Abstract: The incorporation of chloro-alkanol moieties into a urethane-modified isocyanurate foam has been found to improve the insulating properties of the foam as well as improve the flame-retardant properties thereof.Type: GrantFiled: January 23, 1978Date of Patent: August 21, 1979Assignee: BASF Wyandotte CorporationInventors: Thirumurti Narayan, John T. Patton, Jr., Moses Cenker, Harald P. Wulff
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Patent number: 4163830Abstract: The invention relates to a method of making branched polysiloxane-polyoxyalkylene copolymers and to their use as stabilizers in the production of polyurethane foam plastics. The copolymers are made by reacting specified organopolysiloxanes with polyisocyanates, heat treating the NCO--containing addition products to cause branching and reacting the branched NCO--containing addition products with monofunctional polyethers. The copolymers can be used to stabilize polyurethane foam reaction mixtures.Type: GrantFiled: March 13, 1978Date of Patent: August 7, 1979Assignee: Bayer AktiengesellschaftInventors: Erwin Windemuth, Manfred Dahm, Manfred Dietrich, Peter Muller
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Patent number: 4160076Abstract: The invention disclosed is for new improved hydrophilic crosslinked polyurethane foams which simulate natural sponges and prepared by reacting an isocyanate capped polyoxyethylene polyol reactant with an aqueous reactant and a carefully balanced combination of a nonionic surface-active agent and a liquid defoaming agent. The resultant foams are characterized by a majority of large size cells and membranes which themselves are foamed with small cells.Type: GrantFiled: July 15, 1977Date of Patent: July 3, 1979Assignee: W. R. Grace & Co.Inventors: James L. Guthrie, Donald J. Bach
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Patent number: 4152349Abstract: The reactivity of polymethylene polyphenyl isocyanates containing 20 to 90 percent of methylenebis(phenyl isocyanates) is improved, and stabilized against a decline on storage, by incorporating therein very small amounts of a compound of the formula ##STR1## wherein R.sub.1 =alkyl, aryl; R.sub.2 =alkyl; R.sub.3 =H, alkyl or aralkyl; and R.sub.1 and R.sub.2 taken together represent the residue of an oxazoline or oxazine. 2-Ethyloxazoline is the preferred compound for incorporation in the polyisocyanate.Type: GrantFiled: February 22, 1978Date of Patent: May 1, 1979Assignee: The Upjohn CompanyInventor: Warren J. Rabourn
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Patent number: 4148734Abstract: This invention relates to filter material consisting substantially of a microporous and/or macroporous sheet structure obtained by coagulation of a polymer solution in which at least one surface area of the sheet structure is abraded more or less, depending on the desired pore size and a process for producing said filter materials.Type: GrantFiled: August 15, 1977Date of Patent: April 10, 1979Assignees: Chemie-Anlagenbau Bischofsheim GmbH, Reuter Technologie GmbHInventors: Karl H. Hilterhaus, Franz G. Reuter
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Patent number: 4146688Abstract: This invention relates to new polyurethane resins produced by a process in which aromatic diamines containing thio-groups are used as chain-lengthening agents.Type: GrantFiled: August 22, 1977Date of Patent: March 27, 1979Assignee: Bayer AktiengesellschaftInventors: Jurgen Schwindt, Gerhard Grogler, Paul Uhrhan
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Patent number: 4143014Abstract: Storage stable aqueous solutions derived from polymethylene polyphenyl polyisocyanates are described, which solutions are useful as sealant coating compositions for wood and other substrates and, in the form of emulsions with polyisocyanates, as improved particle board binders. The storage stable aqueous solutions are obtained by admixing polymethylene polyphenyl polyisocyanates with less than a stoichiometric amount of a polyethylene glycol (MW 600 to 3000) or polypropylene glycol tipped with 15 to 85 percent ethylene oxide (MW 1000 to 3500) and, within a short time of completing the admixture but during the period where said mixture is completely soluble in water, dissolving said mixture in water. Optionally, a difunctional extender is added to the resulting solution in amount less than that required to react with all the isocyanate groups.Type: GrantFiled: November 9, 1977Date of Patent: March 6, 1979Assignee: The Upjohn CompanyInventors: Alexander McLaughlin, Harold E. Reymore, Jr., Reinhard H. Richter
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Patent number: 4137200Abstract: The invention disclosed is for new improved hydrophilic crosslinked polyurethane foams prepared by reacting a blend of a monomeric polyol and polyoxyalkylene glycol (the --OH groups of said blend being capped with a polyisocyanate) with large amounts of an aqueous reactant. The resultant foams may be characterized with a broad spectrum of improved properties including hydrolytic stability and tensile strength.Type: GrantFiled: June 10, 1977Date of Patent: January 30, 1979Assignee: W. R. Grace & Co.Inventors: Louis L. Wood, Kurt C. Frisch
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Patent number: 4132839Abstract: Disclosed herein are novel prepolymers which, when foamed provide hydrophilic polyurethane foams which are biodegradable.Type: GrantFiled: September 16, 1977Date of Patent: January 2, 1979Assignee: W. R. Grace & Co.Inventors: Nelson S. Marans, Alan R. Pollack
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Patent number: 4129694Abstract: The invention disclosed relates to a new fabric softener foam having improved utility for softening textile fabrics in either a standard or automatic clothes dryer as well as in an automatic washer.Type: GrantFiled: April 7, 1976Date of Patent: December 12, 1978Assignee: W. R. Grace & Co.Inventors: Joseph A. Cogliano, Clifton L. Kehr
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Patent number: 4127515Abstract: A hydrophilic flexible open-celled poly (urea/urethane) sponge derived from prepolymer produced by reaction of a polyoxyalkylene polyol with a stoichiometric excess of an organic polyisocyanate, said sponge containing uniformly distributed therethrough a readily releasable wax composition, and methods of making and using same for waxing surfaces.Type: GrantFiled: November 1, 1976Date of Patent: November 28, 1978Assignee: Colgate-Palmolive CompanyInventors: David M. MacRae, Karl H. Roberts
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Patent number: 4127516Abstract: Disclosed herein is a polyurethane foam having good wet strength. The foam is prepared by reacting a urethane prepolymer with large amounts of water containing a poly(amino)urea and optionally other ingredients, e.g. surfactants. The poly(amino)urea is characterized as being the water soluble reaction product of a polyamine with a urethane prepolymer, said reaction product being further reacted with a crosslinking agent, e.g. epichlorohydrin.Type: GrantFiled: February 28, 1977Date of Patent: November 28, 1978Assignee: W. R. Grace & Co.Inventors: Donald W. Larsen, Louis L. Wood
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Patent number: 4127124Abstract: Bioimplant three dimensional latice of hydrophilic polyurethane having a backbone of polyetherol or polyesterol, end-capped with aliphatic or aromatic diisocyanate, chain branched with polyol and bound into a latice by chain extension alkyl diols. The method of producing such a latice. An extension would be the use of the latice for other medical and veterinary purposes.Type: GrantFiled: May 12, 1977Date of Patent: November 28, 1978Assignee: W. R. Grace & Co.Inventors: Donald C. Clagett, Michael J. Svetly, Peter H. Scott
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Patent number: 4125693Abstract: Process for the production of polyurethanes dissolved in a solvent by mixing linear pre-adducts having terminal NCO groups dissolved in solvents with hydrazines and/or dihydrazine compounds and or diamines dissolved in solvents, for the purpose of forming partially cross-linked polyurethanes, whilst continuously measuring the viscosity until the viscosity shows a value which is located in the shaded zone of the section of curves shown in FIG. 1, the addition of the pre-adduct solution being carried out at such a speed that the final solution has solids content of between 25 and 35 per cent by weight, and coagulation of the obtained solution to fabricated shapes, especially to microporous sheet structures.Type: GrantFiled: February 28, 1977Date of Patent: November 14, 1978Assignees: Chemie-Anlagenbau Bischofsheim GmbH, Metallgesellschaft AGInventor: Karl-Heinz Hilterhaus
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Patent number: 4125691Abstract: A zero pressure device is composed of either a microcellular or homogeneous polyurethane made by reacting an organic polyisocyanate with at least three polyols, a monomeric polyol of 2 to 3 hydroxyls having a molecular weight less than 250, a polyether triol having a molecular weight of 4600 to 6000 and a polyether glycol having a molecular weight of 3500 to 4200. When the zero pressured device is a run-flat ring for a tire wheel assembly, it has an average density of 60 to 65 pounds per cubic foot and 30 to 42 pounds per cubic foot when it is a tire.Type: GrantFiled: April 1, 1977Date of Patent: November 14, 1978Assignee: The Goodyear Tire & Rubber CompanyInventor: John R. White
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Patent number: 4119584Abstract: This invention provides a low density (<2 pcf.) modified phenolic foam produced by combining a resole resin with a phosphorus-containing isocyanate-terminated prepolymer in the presence of a minor amount of a surfactant, a catalytic amount of an organotin catalyst, and a halocarbon blowing agent. Foam products producted by the method of the invention have a good combination of low combustibility, friability resistance and compressive strength.Type: GrantFiled: March 25, 1977Date of Patent: October 10, 1978Assignee: Union Carbide CorporationInventors: Anthony Joseph Papa, Richard Lee Rollins, Frank Edward Critchfield
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Patent number: 4116893Abstract: An impact energy-absorbing, relatively low density, urethane foam for use in automobile bumpers has a high content of urea linkages and is relatively temperature insensitive, i.e. gives approximately the same physical performance over a wide range of temperature. The foam is water blown in a closed mold from a quasi-prepolymer system. The pack factor is preferably in the range of 1.5 to 8 and the molded density is in the range of 5 to 20 lbs./ft..sup.3.The foam formulation is based on a polyol of a poly (oxypropylene/ethylene) triol reacted with a styrene/acrylonitrile monomer mixture which triol thus modified is reacted with (1) a 50 to 150 equivalent weight polyol cross linker of 2 to 6 functionality, (2) a MDI or TDI/glycol or triol quasi-prepolymer and (3) some water.Type: GrantFiled: December 2, 1976Date of Patent: September 26, 1978Assignee: McCord CorporationInventor: Kirby E. L. Flanagan
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Patent number: 4115429Abstract: The instant invention is directed to novel low temperature, storage stable liquid diphenylmethane diisocyanates and to the method of their preparation. The diisocyanates of the instant invention are provided by reacting diphenylmethane diisocyanates having a specified 2,4'-isomer content with polyoxyethylene glycols having molecular weights of from 150 to 1500. It has been surprisingly found that the products of the instant invention are both stable and liquid at -5.degree. C for at least 48 hours. In fact, in many instances, the products of the instant invention show no tendency to crystallize even when stored at -22.degree. C for 100 hours.Type: GrantFiled: March 18, 1977Date of Patent: September 19, 1978Assignee: Mobay Chemical CorporationInventors: Helmut F. Reiff, Richard S. Pantone
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Patent number: 4107100Abstract: This invention deals with porous, substantially foam-free composite material of grainy solid material particles of a certain grain size, which is solidified with a binder mixture of isocyanate-group-containing prepolymers, water, and possibly auxiliaries, and the manufacture and application of such products.Type: GrantFiled: June 6, 1975Date of Patent: August 15, 1978Assignee: BASF Wyandotte CorporationInventors: Josef Peterhans, Otto Volkert, Wilhelm Friedrich Beckerle
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Patent number: 4105595Abstract: The instant invention relates to an improved process for the production of cold-hardening polyurethane foams through the reaction of modified polyisocyanates with compounds having at least two active hydrogen atoms in the presence of blowing agents. The improved process is characterized by the fact that the modified polyisocyanate is prepared in a preliminary stage immediately before foaming.Type: GrantFiled: June 6, 1977Date of Patent: August 8, 1978Assignee: Bayer AktiengesellschaftInventors: Karl H. Eisenmann, Karl H. Broch
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Patent number: 4105597Abstract: An oxyalkylated product useful for making polyurethane foams is prepared by reacting an alkylene oxide with a heated mixture of a phenol and a non-phenolic active hydrogen compound, at least one of which can be halogenated, in the presence of a catalyst complex of a phenol and an iron or aluminum substance. The mixture can also include a neutral phosphorus compound and/or acid anhydrides to enhance flame retardant properties. Optionally, also, the oxyalkylation reaction can be terminated by adding a tri (lower alkyl) amine and alkylene oxide to react with residual phenolic hydrogen in the mixture.Type: GrantFiled: August 15, 1977Date of Patent: August 8, 1978Assignee: BASF Wyandotte CorporationInventors: Arthur L. Austin, William W. Levis, Jr., Louis C. Pizzini, Robert J. Hartman
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Patent number: 4105594Abstract: The instant invention relates to hydrophobic inorganic-organic lightweight foams produced from aqueous suspensions of finely divided water-insoluble inorganic materials and polyisocyanates. More particularly, the invention relates to a process for the production of highly filled, hydrophobic, lightweight polyurea foams comprising reacting(a) liquid, water insoluble polyisocyanates free from ionic groups, having viscosities of more than 200 cP at 25.degree. C. and having isocyanate functionalities of greater than 2.1, with(b) an aqueous suspension of inorganic filler, said suspension having a solids content of from 30 to 80 percent by weight and having a pH value of above 8, at least 50 percent by weight of the suspended fillers having a particle size of less than 50 microns,(c) in the presence of the foam stabilizer of the polyether/polysiloxane type and in the presence of a tertiary amine catalyst,The weight ratio of components (b) to component (a) being better 1:2 and 6:1.Type: GrantFiled: May 18, 1976Date of Patent: August 8, 1978Assignee: Bayer AktiengesellschaftInventors: Dieter Dieterich, Peter Markusch
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Patent number: 4102833Abstract: A quasi-prepolymer-type urethane foam for a reaction injection molding (RIM) system comprises, for the polyol side, a blend of a long-chain polyol with a short-chain diol and/or triol and an organometallic catalyst and, for the prepolymer side, a unique high--27 to 31% --free NCO quasi-prepolymer made by reacting an essentially pure MDI with a selected low molecular weight (240 to 1500) polyol having a functionality of about 2.7 to 3.3. The selected low molecular weight polyol is specifically a polyether polyol (i.e. a polyoxpropylene and/or ethylene polyol) initiated with TMP, hexanetriol, glycerine or other suitable polyol. The quasi-prepolymer, while having the expected high reactivity, surprisingly gives good rapid cures in less than 2 minutes. The resulting urethane foam is characterized by its excellent low temperature properties, especially -20% F cold flexibility and -20% F dart impact. The quasi-prepolymer storage stability can be greatly improved by the inclusion of a small amount of a liquid MDI.Type: GrantFiled: March 16, 1977Date of Patent: July 25, 1978Assignee: McCord CorporationInventor: Wayne C. Salisbury
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Patent number: 4098773Abstract: The invention concerns a process for making heat-resistant polyurethane elastomers from substantially linear polyhydroxyl compounds of high molecular weight, polyisocyanates, chain extenders, and, if desired, catalysts and additives, in which the polyhydroxyl compound is reacted with diisocyanate material in amounts to give an OH:NCO ratio of 1:1.10 to 1:2 and produce an adduct, and the adduct is subsequently reacted with symmetrical aromatic diisocyanate and a diol as chain extender (preferably a linear diol containing 2,4 or 6 carbon atoms) to obtain a crystalline or crystallizable diurethane or polyurethane of good heat resistance.Type: GrantFiled: October 8, 1976Date of Patent: July 4, 1978Assignee: BASF Wyandotte CorporationInventors: Karl Heinz Illers, Herbert Stutz