Granted Patent B2

US 12,650,183 · App. 18/098,526 · Granted Jun 9, 2026

Inventors: Thibaut Montanari (Menneval, FR); Christelle Recoquille (Nassandres, FR); Bertrand Verbauwhede (Aclou, FR); Nicolas Dufaure (Bernay, FR); Florent Dechamps (Saint Romain de Colbose, FR)

Assignee: Arkema France

F16L11/045B32B1/08B32B27/08B32B27/18B32B27/22B32B27/286B32B27/304B32B27/306B32B27/322B32B27/34C08L77/02C08L77/06F16L11/125B32B2307/7265B32B2597/00B32B2605/08F16L11/04F16L2011/047Y10T428/1393

Abstract

Claims (26)

1 . A multilayer tubular structure (MLT) suitable for the transport of fuels, wherein the MLT comprises, from an outer surface of the MLT inward:

a first outer layer comprising from 0 to 15% by weight of a plasticizer relative to the total weight of the composition of the outer layer, the first outer layer comprising a polyamide selected from the group consisting of PA11, PA12, PA610, PA612, PA1012, the corresponding copolyamides thereof, and mixtures thereof;

a second binder layer having a thickness of at most 15% of the total thickness of the MLT, the second binder layer comprising a polyamide mixture selected from the group consisting of the binary mixtures: PA6 and PA12, PA6 and PA612, PA6 and PA610, PA12 and PA612, PA12 and PA610, PA1010 and PA612, PA1010 and PA610, PA1012 and PA612, and PA1012 and PA610;

a barrier layer comprising EVOH and an impact modifier;

a first binder layer having a thickness of at most 15% of the total thickness of the MLT, the first binder layer comprising a polyamide mixture selected from the group consisting of the binary mixtures: PA6 and PA12, PA6 and PA612, PA6 and PA610, PA12 and PA612, PA12 and PA610, PA1010 and PA612, PA1010 and PA610, PA1012 and PA612, and PA1012 and PA610; and

an inner layer comprising at least one aliphatic polyamide, wherein the at least one aliphatic polyamide is selected from the group consisting of PA610, PA612, the corresponding copolyamides thereof, and mixtures thereof, and

wherein the inner layer, first binder layer, and all layers located inward of the barrier layer do not contain plasticizer, and

wherein the MLT exhibits an extractables value of less than or equal to 6 g/m 2 of tube inner surface area after being filled with an alcohol-containing petrol FAM B and heated at 60° C. for 96 hours,

said extractables value determined after heating by emptying and filtering the alcohol-containing petrol into a beaker to obtain a filtrate, evaporating the filtrate at room temperature to obtain a residue of the filtrate, and weighing the residue of the filtrate.

2 . The MLT according to claim 1 , wherein the EVOH of the barrier layer comprises up to 27% of ethylene.

3 . The MLT according to claim 1 , wherein at least one of the inner layer, the first outer layer, the first binder layer and the second binder layer comprises at least one of an impact modifier and at least one other additive.

4 . The MLT according to claim 1 , wherein a polyamide of at least one of the first outer layer, second binder layer, first binder layer, and inner layer is a conductive polyamide.

5 . The MLT according to claim 1 , wherein the first 50% of the thickness of the MLT, starting from the inner layer outward, contains no more than 1.5% by weight of plasticizer.

6 . The MLT according to claim 1 , wherein the first 75% of the thickness of the MLT, starting from the inner layer outward, contains no more than 1.5% by weight of plasticizer.

7 . The MLT according to claim 1 , wherein the first 85% of the thickness of the MLT, starting from the inner layer outward, contains no more than 1.5% by weight of plasticizer.

8 . The MLT according to claim 1 , wherein the first 50% of the thickness of the MLT, starting from the inner layer outward, does not contain plasticizer.

9 . The MLT according to claim 1 , wherein the first 75% of the thickness of the MLT, starting from the inner layer outward, does not contain plasticizer.

10 . A method of using the MLT according to claim 1 , wherein the method comprises the steps of a) providing the multilayer tubular structure, b) filling the multilayer tubular structure with fuel, and c) transporting the fuel from one location to another.

11 . A method of determining whether the MLT according to claim 1 complies with an extractables test, wherein the method comprises the following steps:

a) determining an inner surface area of the MLT of claim 1 ;

b) filling the MLT with an alcohol-containing petrol FAM B according to DIN 51604-1:1982, DIN 51604-2:1984, and DIN 51604-3:1984 to obtain a filled MLT;

c) heating the filled MLT at 60° C. for 96 hours;

d) emptying the filled MLT after heating by filtering the alcohol-containing petrol into a beaker to obtain a filtrate;

e) leaving the filtrate to evaporate at room temperature to obtain a residue of the filtrate; and

f) weighing the residue of the filtrate;

wherein compliance with the extractables test is defined as the weight of the residue of the filtrate must be less than or equal to 6 g/m 2 of the inner surface area of the MLT.

Assignments (2)

Priority Claims (1)

Continuity (3)

References Cited (202)