Multilayered gas-tight and anti-puncture laminate object including same

1. A puncture-resistant multilayer laminate that is impermeable to inflation gases, usable in an inflatable article, comprising:

a gastight first elastomer layer comprising a thermoplastic elastomer copolymer with polystyrene and polyisobutylene blocks (hereinafter “first elastomer”), and optionally an extender oil with a content within a range of 0 to less than 100 phr

wherein said first elastomer represents more than 70% by weight of all elastomers present in said gastight first elastomer layer; and

a self-sealing second elastomer layer comprising a thermoplastic styrene elastomer (hereinbelow “second elastomer”), identical to or different from the first elastomer, and an extender oil with a content greater than 200 phr

wherein said second elastomer represents more than 70% by weight of all elastomers present in said self-sealing second elastomer layer.

2. The laminate according to claim 1 , wherein the first elastomer is a styrene/isobutylene/styrene (SIBS) copolymer.

3. The laminate according to claim 1 , wherein the first elastomer is, in the first elastomer layer, the sole elastomer or the predominant elastomer by weight.

4. The laminate according to claim 1 , wherein the second elastomer is chosen from the group consisting of styrene/butadiene/styrene block copolymers, styrene/isoprene/styrene block copolymers, styrene/isobutylene/styrene block copolymers, styrene/isoprene/butadiene/styrene block copolymers, styrene/ethylene-butylene/styrene block copolymers, styrene/ethylene-propylene/styrene block copolymers, styrene/ethylene-ethylene-propylene/styrene block copolymers and mixtures of these copolymers.

5. The laminate according to claim 4 , wherein the second elastomer is chosen from the group consisting of styrene/ethylene-butylene/styrene block copolymers, styrene/ethylene-propylene/styrene block copolymers, and mixtures of these copolymers.

6. The laminate according to claim 1 , wherein the second elastomer is, in the second elastomer layer, the sole elastomer or the predominant elastomer by weight.

7. The laminate according to claim 1 , wherein the first elastomer and the second elastomer each comprise between 5 and 50% by weight of styrene.

8. The laminate according to claim 1 , wherein the first elastomer and the second elastomer each have a glass transition temperature (T g ) which is below −20° C.

9. The laminate according to claim 1 , wherein the number-average molecular weight (M n ) of the first elastomer is between 30 000 and 500 000 g/mol.

10. The laminate according to claim 1 , wherein the number-average molecular weight (M n ) of the second elastomer is between 50 000 and 500 000 g/mol.

11. The laminate according to claim 1 , wherein the extender oil of the first elastomer and the extender oil of the second elastomer, which are identical or different, are chosen from the group consisting of polyolefin oils, paraffinic oils, naphthenic oils, aromatic oils, mineral oils and mixtures of these oils.

12. The laminate according to claim 11 , wherein the extender oil of the first elastomer and the extender oil of the second elastomer, which are identical or different, are chosen from the group consisting of polybutene oils, paraffinic oils and mixtures of these oils.

13. The laminate according to claim 12 , wherein the extender oil of the first elastomer and the extender oil of the second elastomer, which are identical or different, are polyisobutylene oils.

14. The laminate according to claim 1 , wherein the number-average molecular weight (M n ) of the extender oil of the first elastomer and the molecular weight (M n ) of the extender oil of the second elastomer are each between 200 and 30 000 g/mol.

15. The laminate according to claim 1 , wherein the extender oil content of the first elastomer is between 5 and 100 phr.

16. The laminate according to claim 1 , wherein the extender oil content of the second elastomer is between 200 and 700 phr.

17. The laminate according to claim 1 , wherein the first elastomer layer has a thickness of greater than 0.05 mm.

18. The laminate according to claim 1 , wherein the second elastomer layer has a thickness of greater than 0.3 mm.

19. An inflatable article comprising a laminate according to claim 1 .

20. An inflatable article according to claim 19 , said article being a rubber article.

21. An inflatable article according to claim 20 , said inflatable article being a pneumatic tire.

22. An inflatable article according to claim 20 , said inflatable article being an inner tube.

23. The laminate according to claim 17 , wherein the first elastomer layer has a thickness between 0.1 mm and 10 mm.

24. The laminate according to claim 18 , wherein the second elastomer layer has a thickness between 0.5 mm and 10 mm.