Abstract: A continuous process for the production of thermoplastically processable polyurethane elastomer is disclosed. The process comprise adding acid H compounds in an amount calculated to control and render constant the melt viscosity of the product. The inventive elastomer has constant melt flow behavior and high thermal stability.

Abstract: Polyurethane moulding compositions which can be melt processed in the form of sintering powders suitable for the preparation of grained sintered films and which are prepared exclusively from linear aliphatic components are described. The polyol component is composed of 30 to 80 parts by weight of an aliphatic polycarbonate diol with an average molecular weight {overscore (M)}n of 1000 to 2200 and 70 to 20 parts by weight of a polybutane diol adipate and/or a polycaprolactone diol with an average molecular weight {overscore (M)}n of 1000 to 2400. Moreover, the mixture contains 1,6-hexamethylene diisocyanate in an equivalence ratio of 2.3:1.0 to 6.2:1.0, based on the polyol mixture and butane-1,4-diol as chain extender, the equivalence ratio of the butane-1,4-diol based on the poly mixture being 1.3:1.0 to 5.2:1.0.

Abstract: A light-stable, sinterable particulate thermoplastic molding composition is described. The thermoplastic compositions of the present invention consist essentially of: (i) a resinous blend of, (a) thermoplastic polyurethane, and (b) a member selected from at least one of a number of recited copolymers, e.g., a styrene-acrylonitrile copolymer; (ii) a UV stabilizer; and (iii) an antioxidant. The thermoplastic polyurethane (a) is prepared from an aliphatic or cycloaliphatic diisocyanate. The molding compositions are suitable for the preparation of textured sintered films, e.g., by the powder-slush process, having improved tactile properties that, for example, may be used in the fabrication of vehicle interior trim components and vehicle air bags.

Abstract: Process for the continuous preparation of thermoplastically processable polyurethane elastomers with improved softening properties is disclosed. The process is carried out in a tubular reactor at a ratio of the circumferential speed of the stirrer (in m/sec) in the tubular reactor and the throughput (in g/sec) of >0.03 m/g.

Abstract: A process for the continuous preparation of melt processable polyurethane elastomers having improved softening behavior is disclosed. The process entails reacting a polyisocyanate, a polyol and a chain extender, which have a temperature of at least 170° C., in a static mixer, wherein the reaction mixture is prepared. The reaction mixture is then metered into an extruder into which optional auxiliaries and/or further components are fed.

Abstract: A moulded article comprising thermoplastic polyurethane (TPU) that exhibits reduced fogging is disclosed.

Abstract: A molding composition comprising thermoplastic polyurethane is disclosed. The polyurethane is characterized in having ultimate tensile strength (UTS) and elongation at break (EAB) values after hot storage which are, each, at least 60% of the corresponding value before hot storage, glass transition temperature equal to or lower than −50° C., UTS and EAB values after hydrolytic storage which are, each, at least 80% of the corresponding value before hydrolytic storage, and Shore A hardness of 70 to 95. The polyurethane is a product of a reaction comprising an aliphatic diisocyanate, a mixture of polyols and a chain extender and contains a UV stabilizer, an antioxidant and an optional anti-hydrolysis agent.

Abstract: A thermoplastic molding composition that contains an aliphatic thermoplastic polyurethane (TPU) resin is disclosed. The TPU is the product of a reaction of A) a diisocyanate reactant that contains predominantly hexamethylene diisocyanate, and B) a polyol reactant that contains polytetramethylene glycol and C) a chain extending reactant that contains primarily 1,6-hexanediol. The TPU that is further characterized in the equivalence ratio of A to B and NCO index exhibits improved properties.

Abstract: This invention relates to thermoplastically processable, readily demouldable moulding compositions with low shrinkage and with a hardness of 65 to 85 Shore A, consisting of a mixture of A) a thermoplastic polyurethane of hardness 60 to 75 Shore A and B) a thermoplastic polyurethane of hardness 76 to 90 Shore A, which is produced continuously by a special multi-stage process.

Abstract: The invention relates to light-stable sinterable thermoplastic polyurethane molding compositions of reduced mechanical strength which can be processed by the powder-slush process. The molding compositions according to the invention are particular suitable for the production of grained sintered films for interior lining of means of transport, in particular as a covering for airbags in motor vehicles.

Abstract: A thermoplastic polyurethane elastomer is disclosed obtained by reactingA) diisocyanates,B) polyhydroxy compounds and/or polyamines, withC) as chain extenders mixtures ofC1) benzene substituted with at least two hydroxyalkyl, hydroxyalkoxy, aminoalkyl and/or aminoalkoxy groups andC2) an alkanediol with 4 to 44 C atoms. The reaction is further characterized in that the molar ratio C1 to C2=60 to 40 to 95 to 5 and in that the equivalent ratio of NCO groups to the sum of the NCO-reactive groups is about 0.9 to 1.20.

Abstract: A process for the continuous production of a thermoplastic molding composition containing a mixture of a TPU and a thermoplastic (co)polymer is disclosed.

Abstract: A process for the preparation of a polyurethane-urea elastomer having a mole ratio of NCO groups to all active hydrogen atoms in the range of 0.9 to 1.2 is disclosed. The process comprise reacting (A), (B) and (C.2) for form an NCO-containing prepolymer and then reacting said prepolymer with (C.1) and (D). Accordingly (A) is 5-isocyanato-1-(isocyanatomethyl)-1,1,3-trimethylcyclohexane or bis-(4-isocyanatocyclohexyl)-methane,(B) is polytetrahydrofuran or hexanediol polycarbonate and (C.2) is a chain extender. (C.1) is 5-amino-3-amino-methyl-1,3,3-trimethylcyclohexane or bis-(4-aminocyclohexyl)-methane and (D) is a molecular weight regulator. The elastomer thus produced is particularly suitable for the preparation of moldings, films, flexible tubing (for medical purposes) and catheters.

Abstract: A thermoplastic molding composition comprising a thermoplastic polyurethane and a wax mixture is disclosed. The polyurethane is a product of an organic diisocyanate, a linear, hydroxyl-terminated polyol and a diol or diamine chain extender. The wax mixture contains a first mixture of an ester of a C.sub.10-45 aliphatic carboxylic acid and a diol, and an alkali metal or alkaline earth metal salt of a C.sub.10-45 aliphatic carboxylic acids, and at least one member selected from the group consisting of fatty acid ester, fatty acid amide, fatty acid ester amide and polyethylene wax.

Abstract: A thermoplastsic molding composition comprising thermoplastic polyurethane resin and about 0.05 to 2 percent of a wax is disclosed. The composition which offers processing advantages, including release and cosmetic properties, is characterized in that the wax contains acylation products of hydroxy groups and of amino groups of amino alcohols.

Abstract: The present invention relates to a process for the continuous production of thermoplastically processable polyurethanes having improved processing behaviour, wherein in a multistep reactionA) one or more linear hydroxyl-terminated polyols a) having a molecular weight of from 500 to 5000 are mixed continuously with a proportion of an organic diisocyanate b) in an NCO:OH ratio of from 2.0:1 to 5.0:1, in a mixing unit at high shear energy,B) the mixture prepared in step A) is reacted continuously to form an isocyanate-terminated prepolymer in a reactor at temperatures of >120.degree. C., until a conversion of >90%, referred to component a), is achieved,C) the prepolymer prepared in step B) is mixed with the remainder of component b), an NCO:OH ratio of from 2.05:1 to 6:1 being established overall in steps A) to C) and an NCO:OH ratio of 0.9 to 1.1 being established when all the components of steps A) to F) are included,D) the mixture prepared in step C) is cooled to a temperature of <190.degree. C.

Abstract: A process for the continuous production of a thermoplastic molding composition containing a mixture of a TPU and a thermoplastic (co)polymer is disclosed.

Abstract: A process for the preparation of thermoplastic polyurethaneurea elastomers is disclosed. Accordingly, organic polyisocyanates (A) and a mixture (B) containing Zerewitinoff active hydrogen atoms, are reacted to yield an intermediate product. The intermediate product is then chain extended by thermal decomposition. Reactant (B) containsB1) 40 to 85 equivalent-% (relative to isocyanate groups in (A)) at least compound having an average of at least 1.8 to 3.0, preferably 2.0, Zerewitinoff active hydrogen atoms and a molecular weight of 400 to 10000, andB2) 10 to 60 equivalent-% (relative to isocyanate groups in (A)) of at least one specifically recited tertiary hydroxyl compounds.

Abstract: A process for the continuous production of a thermoplastic molding composition containing a mixture of TPU and a (co)polymer is disclosed. The process comprises(a) introducing into an extruder under time and temperature conditions sufficient to bring about the formation of thermoplastic polyurethane a (co)polymer, and polyurethane-forming components comprising A) an organic diisocyanate, B) a linear polyol having terminal hydroxyl groups and a molecular weight of 500 to 5000, and C) a chain extender having a molecular weight of 60 to 500, and upon completing the formation of said polyurethane(b) discharging the resulting TPU/(co)polymer mixture from the extruder. Importantly, the (co)polymer contains a flow enhancer and the molar ratio of the NCO groups in A) to the groups which react with NCO in B) and C) is 0.9 to 1.2.

Abstract: This invention relates to novel polycarbonates having hydroxyl end groups and an average molecular weight of 500 to 12,000, as determined by measuring the OH number, and being based on dimer diols containing either 36 or 44 carbon atoms. These novel polycarbonates are particularly suitable for the use in a process for the production of polyurethane plastics which are stable to hydrolysis and oxidation.