A chafe layer for a fluid conduit, wherein the chafe layer consists of thermoplastic polyurethane which contains a polyol, in particular a short-chained, diol as a chain extender and isocyanate. The polyol is a polycarbonate. A fluid conduit, a method for producing a fluid conduit as well as the use of a polyurethane and the use of an ethylene copolymer as an additive.

A thermoplastic polyurethane (TPU) foam product with high flatness, and a preparation method and a use thereof are provided. The TPU foam product is prepared by processing aliphatic thermoplastic polyurethane (ATPU) beads with a melting range of 20° C. to 50° C. and a melting point of 90° C. to 160° C. by a physical gas foaming process to obtain foamed ATPU beads and heating the foamed ATPU beads with a heat source to make the foamed ATPU beads fused. The TPU foam product with high flatness has a density of 0.08 g/cm.sup.3 to 0.8 g/cm.sup.3 and a flatness value of less than 2 mm, and the flatness value is determined by a fixed-length ruler. The TPU foam product not only has high flatness such that diversified designs are allowed for a surface of the product, but also has high resilience.

The invention relates to a thermoplastic moulding composition comprising A) at least one thermoplastic polyurethane polymer obtainable by reacting at least the following constituent components: I) one or more aliphatic diisocyanates having a molecular weight of between 140 g/mol to 170 g/mol and II) one or more aliphatic diols having a molecular weight of between 62 g/mol to 120 g/mol, the constituent components used to produce the thermoplastic polyurethane polymer consisting of at least 95% by weight of one or more aliphatic diisocyanates I) and one or more aliphatic diols II), based on the total mass of the constituent components used, wherein the one or more aliphatic diisocyanates I) and the one or more aliphatic diols II) are present in a molar ratio in the range from 1:0:0.95 to 0.95:1.0, characterized in that the ratio (I) of the thermoplastic polyurethane polymer is in a range from 2.3 to 6, wherein (II) is the molar mass centrifugal agent and (III) is the molar mass average, in each case determined by gel permeation chromatography in hexafluoroisopropanol against polymethyl methacrylate as standard, also comprising B) at least one mould release agent. The invention also relates to the use of the moulding composition for producing mouldings and to the mouldings thereof.

An article is prepared by injection molding, wherein the article is formed from a hydrophilic thermoplastic polyurethane composition, wherein the thermoplastic polyurethane composition comprises the reaction product of a hydroxyl terminated polyol intermediate component, an aliphatic isocyanate component, and, optionally, a chain extender component. For injection molding, the hydrophilic thermoplastic polyurethane has a crystallization temperature measured by dynamic scanning calorimetry of at least 75° C.

The present invention relates to thermoplastic polyurethanes obtainable or obtained by reacting at least a polyisocyanate composition comprising at least one polyisocyanate, at least one chain extender, and at least one polyol composition, wherein the polyol composition comprises at least one polyester polyol (P1) which is obtainable by reacting an aliphatic dicarboxylic acid having 2 to 12 carbon atoms and a mixture (M1) comprising propane-1,3-diol and a further diol (D1) having 2 to 12 carbon atoms, preferably butane-1,4-diol. The present invention also relates to a preparation process for such thermoplastic polyurethanes and also to the use of a thermoplastic polyurethane according to the invention or of a thermoplastic polyurethane obtainable or obtained by a process according to the invention for the production of extrusion products, films and shaped bodies or for the production of polymer compositions.

The invention relates to a method for producing a thermoplastic polyurethane (G) using a reactive extrusion process, having the steps of: a) mixing a polyisocyanate stream (A) and a polyol stream (B) in a first mixing device (7) such that a mixture stream (C) is obtained, the mass flow rates of the polyisocyanate stream (A) and the polyol stream (B) being set such that the isocyanate index in the mixture stream (C) ranges from 55 to 85, b) introducing the mixture stream (C) into a circulating stream (D) which is conducted in a circular flow, the monomers of the polyisocyanates stream (A) and the polyol stream (B) in the circulating stream (D) being further reacted into OH-functional pre-polymers, c) separating a sub-stream from the circulating stream (D) as a prepolymer stream (E) and introducing same into an extruder (18), d) introducing an isocyanate feed stream (F) into the extruder (18) downstream of the introduction point of the prepolymer stream (E) in the extruder working direction, wherein the introduction process is carried out such that the OH-functional prepolymers contained in the prepolymer stream (E) and the polyisocyanate contained in the isocyanate feed stream (F) are in an isocyanate index of 85 to 120, and e) reacting the prepolymer stream (E) with the isocyanate feed stream (F) in the extruder (18), thereby obtaining the thermoplastic polyurethane (G) as the extrudate.

The invention provides a method for the production of a cross-linked polyester moulded article.

The present invention relates to hydroxy-terminated polyurethane prepolymers that consist to an extent of at least 90% by weight of the product of the reaction of hexamethylene 1,6-diisocyanate with butane-1,4-diol and have an allophanate content of ≤1.00 mol %, to a process for the production thereof, to compositions comprising such polyurethane prepolymers and to the use of said polyurethane prepolymers.

The invention relates to a multi-stage process for the continuous preparation of thermoplastic polyurethanes by reacting one or more aliphatic, cycloaliphatic and/or araliphatic diols with one or more aliphatic, cycloaliphatic and/or araliphatic diisocyanates, wherein the total reaction enthalpy is ≤−500 kJ/kg over all the process stages at a molar ratio of diol to diisocyanate of 1.0:1.0.

A foamable polypropylene composition, and foamed polypropylene and a preparation method therefor are provided. The polypropylene composition comprises polypropylene, a polypropylene modifier, a foaming agent, and an optional nucleating agent. A preparation method for the polypropylene modifier comprises: enabling polar monomer grafted polypropylene to be in contact with a component A to react and carrying out extruding pelletizing, wherein a polar monomer in the polar monomer grafted polypropylene can chemically react with the component A; the polar monomer is selected from at least one of dimethylamino methacrylate, epoxy acrylate, trimeric acrylic isocyanurate, and acrylamide; and the component A is selected from at least one of polyisocyanate, polyethylene oxide, and an amido-containing substance. The foamed polypropylene has an obtained foaming ratio of 12 times or more, and also has high tensile and flexural properties.