MULTILAYER PLASTIC PIPE

摘要

A plastic pipe having improved resistance to chemicals and improved mechanical properties is disclosed. The pipe comprises an outer layer made of a moulding compound based on a polyamide and an inner layer made of a moulding compound based on polyvinylidene fluoride, as well as three intermediate layers. The intermediate layer adjacent to the outer layer is made of a moulding compound based on a mixture of from 95 -to 99% by weight of a linear crystalline polyester and from 1 to 5% by weight of a compound having at least two isocyanate groups present in the mixture in a concentration of from 0.03 to 0.3% by weight. The intermediate layer adjacent to the inner layer is made of a moulding compound based on a mixture of from 50 to 90% by weight of polyamide and from 10 to 50% by weight of poly(alkyl)acrylic ester. The remaining intermediate layer is made of a moulding compound based on a polyamide. The pipe has an outstanding resistance to and a good barrier action against diffusion of (petro)chemicals, solvents and fuels. Since the adjacent layers are bonded adhesively one to another, no delamination occurs on thermal expansion or flexing of the pipe. The pipe is preferably used in the motor vehicle sector for lines carrying brake, cooling and hydraulic fluids and fuel.