Abstract: The present invention is directed to a process for the production of matte, non-blocking, thin-walled molded articles, films or tubes from polyurethane elastomers prepared from high molecular weight polyols which contain dispersed polyadducts based on polyisocyanate polyaddition products. The use of these high molecular weight polyols contained dispersed polyadducts allows for the preparation of thin-walled, molded articles which have reduced surface tackiness. The present invention is additionally directed to the molded articles produced by this process and to their use for forming polyurethane foam composites.

Abstract: A process for the continuous glycolytic cleavage of polyurethane plastics waste in multi-shaft screw machines by the addition of optionally preheated diols, at a degradation temperature of 250.degree. C., while maintaining a pressure at least such that the polyurethane-diol mixture is in the liquid phase, by the discharge of the glycolysate mixture after short residence times of from 2 to 30 minutes in the reaction screw, and by rapid cooling of the glycolysate mixture.

Abstract: The present invention is directed to a process for separating polyurethane hydrolyzates, preferably polyurethane foam hydrolyzates, into substantially amine-free foamable polyethers and diamines, comprising (a) (i) briefly expanding a hot polyurethane hydrolyzate obtained in a continuous screw extruder to normal pressure or in vacuo and, without using readily volatile components (ii) spraying said hydrolyzate directly into a tubular coil evaporator which is heated to 180.degree.-300.degree. C. and at the end of which a pressure of from 0.1 to 20 mbar is applied and (iii) separating a hydrolyzate containing less than 1% by weight of NH.sub.

Abstract: The invention is directed to a process extruding or melt roll calendering thermoplastic polyurethanes wherein the polyurethanes used are synthesized from p1 (a) one or more relatively high molecular weight substantially linear polyols having molecular weights in the range from 400 to 10,000(b) diphenyl methane and/or hexamethylene diisocyanate and(c) a mixture of 85 to 99% by weight of 1,4-butane diol and 1 to 15% by weight of at least one co-extender selected from the group consisting of ethylene glycol, diethylene glycol, triethylene glycol, diethylene 1,2-propane diol, 1,3-butane diol, 1,6-hexane diol, 2-ethyl-1,3-hexane diol, 2,2-dimethyl-1,3-propane diol, 1,4-bis-hydroxymethyl cyclohexane, hydroquinone-bis-hydroxyethyl ether, and mixtures thereof, the equivalent ratio of NCO groups in component (B) to the Zerewitinoff-active hydrogen atoms in components (A) and (C) being from 0.9:1 to 1.2:1 and the molar ratio of component (A) to (C) being from 1:20 to 5:1.

Abstract: The instant invention is directed to a continuous process for the production of thermoplastic materials, comprising:I. introducing 4 to 65 parts by weight of thermoplastic polymer into an extruder at a first inlet, wherein the temperature within said extruder is such that said thermoplastic polymer melts;II. adding to said thermoplastic polymer through a second inlet 35 to 96 parts by weight of the following polyurethane forming components, such that the total parts by weight of thermoplastic polymer and polyurethane components is 100:(A) organic polyisocyanate; and(B) chain lengthening agent with a molecular weight below 400 containing a hydroxyl group and/or amine group;wherein the ratio of isocyanate groups of component (A) to Zerewitinoff active groups of component (B) is in the range of from 0.90:1 to 1.2:1; andIII. discharging from the extruder the product of the process when the reaction of said polyurethane components (A) and (B) is substantially complete.

Abstract: The present invention relates to a process for the preparation of polyurethane ureas from relatively high molecular weight polyols, diisocyanates, water as chain lengthening agent and optionally short chain glycols in a multishaft extruder equipped with kneading elements.

Abstract: The instant invention is directed to a process for the separation of polyurethane hydrolysates into polyamines and polyols which can be used again for the production of polyurethanes, comprising introducing gaseous hydrogen chloride into the hydrolysate mixture which has optionally been diluted with an inert solvent, and removing the precipitated amine salt by filtration, characterized in that(a) gaseous hydrogen chloride is optionally first introduced into the hydrolysate in a quantity of from 0.02 to 0.07 mol per amine equivalent, the reaction mixture is filtered and the filter residue is discarded, then(b) from 0.20 to 0.

Abstract: The instant invention is directed to a process for the modification of a thermoplastic polymer comprising:I. introducing 70 to 98 parts by weight of thermoplastic polymer into an extruder at a first inlet;II. adding to said thermoplastic polymer through a second inlet 2 to 30 parts by weight of the following polyurethane forming components, such that the total parts by weight of the thermoplastic polymer and polyurethane components is 100:(A) organic polyisocyanate; and(B) chain lengthening agent with a molecular weight below 400 containing at least one hydroxyl group and/or amino group;wherein the ratio of isocyanate groups of component (A) to Zerewitinoff active groups of component (B) is in the range of from 0.90:1 to 1.2:1; andIII. discharging from the extruder the product of the process.

Abstract: The present invention relates to an improved continuous process for the preparation of polyurethane elastomers which are distinguished from the products produced by known processes by increased elasticity, reduced shrinkage, higher rigidity (limit bending stress), improved cold notched bar impact resistance and good thermal stability.

Abstract: The instant invention is directed to a continuous process for the production of thermoplastic polyurethanes by reactingA. one or more substantially linear polyols having molecular weights in the range from 400 to 10,000,B. one or more organic diisocyanates andC. a hydroxyl-group-containing chain extender having a molecular weight below 250,the ratio of the NCO-groups in component (B) to the Zerewitinoff-active groups in components (A) and (C) lying between 0.90 and 1.2, in extruders, characterized in that the chain extender (C) used is a mixture of at least two different glycols, of which one is present in a quantity of from 50 to 99% by weight, based on the total amount of component (C), and a second in a quantity of from 1 to 50% by weight, based on the total amount of component (C).

Abstract: The present disclosure is concerned with an improved method of reverse coating textile sheets with storage stable polyurethane top and adhesive coats which are formulated to have improved resistance to deformation under heat and pressure. At least one of the coats is formulated from a diisocyanate, a high molecular weight dihydroxy compound and a mixture of at least one low molecular weight diol with a low molecular weight monoalkanolamine. The coatings are applied in the usual reverse coating manner, i.e. the top coat is applied to a release substrate from solution; dried; the adhesive coat is applied from solution onto the dried top coat; and the textile substrate is laminated to the adhesive coat.

Abstract: This application relates to textile sheets which have been coated with polyurethanes and to a process for coating said textile sheets wherein a solution of polyurethane is applied as a top coat to a release substrate and then a bonding coat is applied before application of the textile material. The polyurethane which is used as a top coat is prepared by reacting a dihydroxyl compound with a molecular weight between about 600 and 4000 and a mixture of at least 2 diols with a molecular weight between 62 and 450 with at least one organic diisocyanate. The invention overcomes the difficulty of the top coat being lifted from the release substrate in numerous areas while other areas remain firmly attached giving the so-called "hoar-frost" effect.

Abstract: This invention relates to an improved process for the production of high molecular weight polyurethanes which are free from isocyanate groups and are soluble in organic solvent in reduced reaction times. The reactants, polyol and isocyanate, for example, are mixed together with solvent and the temperature is permitted to rise under the effect of the heat of reaction. The reaction mixture is then cooled with solvent addition in such a way that the viscosity of the reaction mixture remains constant until the optimum temperature for the polyurethane formation reaction ("specific reaction temperature") is reached. The mixture is then gradually cooled until there is no residual isocyanate present and the polymer is recovered from the reaction mixture.