Abstract: A plastic pipe based on polyolefins is provided, which pipe, compared with single-layer pipes of polyolefins, has improved barrier action against (petro)chemical materials, in particular against methanol-containing fuels. This is achieved by a multilayer plastic pipe which comprises the following layers: I. at least one layer based on a polyolefin, II. at least one layer based on a thermoplastic polyester, bonded via III. a layer between them of a suitable coupling agent which contains reactive groups, with adjacent layers being cohesively bonded to one another. The invention makes it possible to obtain plastic pipes having the desired improved property profile.

Abstract: A plastic pipe having improved resistance, inter alia, to methanol-containing fuels and improved mechanical properties, comprising at least:(I) an outer layer,(III) an inner layer comprising a moulding composition based on polyvinylidene fluoride, and(II) an intermediate layer disposed between said inner layer (I) and said outer layer (III) comprising a moulding composition based on a mixture of(a) polyamide, and(b) polyglutarimide,wherein the adjacent layers (I) to (III) are each adhesively bonded to one another.

Abstract: The present invention relates to a plastic pipe having improved resistance, inter alia, to methanol-containing fuels and improved mechanical properties, comprising.(I) at least one outer layer,(II) at least one inner layer comprising a polyvinylidene fluoride molding composition, and(III) a layer, disposed between the inner layer II and the outer layer I, comprising a molding composition comprising a mixture of:(a) polyamide and(b) polyalkyl acrylate,wherein the layers (I)-(III) are adhesively bonded to one another.

Abstract: Multilayer plastic pipes comprising a polyamide-based inner and outer layer, wherein the inner and outer layer are connected force-lockingly by means of at least one intermediate layer made of a mixture of a linear crystalline polyester and a polyamide, have improved stability to chemical agents and improved mechanical properties.

Abstract: A plastic pipe having improved resistance, inter alia, to methanol-containing fuels and improved mechanical properties comprising:(I) an outer layer made of a moulding compound based on polyamide,(II) an intermediate layer adjacent to the outer layer and made of a moulding compound based on a mixture of:(a) of from 95 to 99% by weight of a linear crystalline polyester, and(b) of from 1 to 5% by weight of a compound having at least two isocyanate groups,wherein the isocyanate groups originating from component (IIb) are present in the mixture of (IIa) and (IIb) in a concentration of from 0.03 to 0.

Abstract: Multilayer plastic pipe comprising at least one outer layer based on polyamide and at least one layer of a linear, crystalline polyester modified by means of an isocyanate mixture exhibits improved resistance, inter alia, to methanol-containing fuels and improved mechanical properties.

Abstract: A multilayer plastic pipe having improved barrier action against diffusion of the substance being transported, particularly methanol-containing fuels, dimensional stability, resistance to mechanical stress, and particularly improved adhesion between layers is provided comprising:(A) an inner layer and an outer layer, each of which comprise a polyamide-based molding composition, wherein the inner layer and outer layer may be the same or different, and (B) at least one intermediate layer comprisinga) 95 to 60% by weight of a linear, crystalline polyester andb) 5 to 40% by weight of a polymer containing reactive groups other than epoxide groups,wherein the reactive groups are contained in a concentration of from 4 to 95 mmol/kg based on the total amount of component (B); and wherein the layers are intimately bonded to one another.

Abstract: A plastic pipe having improved resistance to methanol-containing fuels and improved mechanical properties is provided. This is achieved by a multilayer plastic pipe consisting of at least one outer layer based on polyamide and at least one layer of a linear, crystalline polyester modified with isocyanates. With the aid of the invention it is possible to obtain plastic pipes having improved barrier properties against methanol-containing fuels and dimensional stability and mechanical load-bearing capacity.