| abstract |
The present invention relates to a multilayer tubular structure (MLT) for transporting a heat transfer fluid, the multilayer tubular structure comprising - at least one long chain polyamide mainly having 10 to 15 carbon atoms per nitrogen atom. at least one layer (1) comprising a composition (1) comprising at least 50% aliphatic units with respect to the sum of units present in said long-chain polyamide comprising: # mainly 4 to 9 carbons per nitrogen atom at least one layer (2) located under said layer (1) comprising a composition (2) comprising at least one long-chain polyamide having atoms, said polyamide being the sum of the units present in said polyamide at least 50% of aliphatic units for layer (2) comprising at most 2% by weight relative to the total weight of at least one plasticizer, # optionally comprising composition (3) as defined for composition (1), or mainly 4 to 7 per nitrogen atom a composition (3') comprising carbon atoms and at least 20% by weight, preferably at least 25% by weight of at least one polyolefin, relative to the total weight of the composition (3'), or at least 50% semi-aromatic units a layer (3) comprising a composition (4) comprising polyamide, said layer (1) containing no continuous fibers, said layer (2) comprising: In contact with the transported fluid, said layer(s) 2 represent at least 50% of the total thickness of the tube. |