ELASTOMERIC LAMINATE FOR A TIRE
An airtight elastomeric laminate for tires comprises at least two superimposed layers of elastomer. The first layer is composed of a composition based on at least one thermoplastic elastomer having polystyrene and polyisobutylene blocks, the content of thermoplastic elastomer having polystyrene and polyisobutylene blocks being within a range extending from more than 50 to 100 phr and on a plasticizing system comprising from 1 to 40 phr of a plasticizing oil and from 1 to 40 phr of a hydrocarbon resin, the total content of plasticizer being within a range extending from 2 to 70 phr. The second layer is composed of a composition based on at least one diene elastomer, the content of diene elastomer being within a range extending from more than 50 to 95 phr, and on at least one thermoplastic styrene elastomer in an amount ranging from 5 to less than 50 phr.
1 .- 33 . (canceled)
34 . An airtight elastomeric laminate for tires comprising at least two superimposed layers of elastomer:
a first layer comprising a composition based on
at least one thermoplastic elastomer having polystyrene and polyisobutylene blocks in an amount ranging from more than 50 to 100 phr, and
a plasticizing system comprising from 1 to 40 phr of a plasticizing oil and from 1 to 40 phr of a hydrocarbon resin, the total content of plasticizer being within a range extending from 2 to 70 phr; and
a second layer comprising a composition based on
at least one diene elastomer in an amount ranging from more than 50 to 95 phr, and
at least one thermoplastic styrene elastomer in an amount ranging from 5 to less than 50 phr.
35 . The laminate according to claim 34 , wherein the at least one thermoplastic elastomer having polystyrene and polyisobutylene blocks of the first layer is a styrene/isobutylene/styrene (SIBS) copolymer.
36 . The laminate according to claim 34 , wherein the amount of the at least one thermoplastic elastomer having polystyrene and polyisobutylene blocks in the composition of the first layer ranges from 70 to 100 phr.
37 . The laminate according to claim 36 , wherein the amount of the at least one thermoplastic elastomer having polystyrene and polyisobutylene blocks in the composition of the first layer ranges from 80 to 100 phr.
38 . The laminate according to claim 37 , wherein the at least one thermoplastic elastomer having polystyrene and polyisobutylene blocks is the only elastomer of the first layer.
39 . The laminate according to claim 34 , wherein the plasticizing system of the first layer comprises from 2 to 30 phr of the plasticizing oil.
40 . The laminate according to claim 39 , wherein the plasticizing system of the first layer comprises from 5 to 20 phr of the plasticizing oil.
41 . The laminate according to claim 34 , wherein the plasticizing oil of the first layer is selected from the group consisting of polyolefinic oils, paraffinic oils, naphthenic oils, aromatic oils, mineral oils and mixtures thereof.
42 . The laminate according to claim 41 , wherein the plasticizing oil of the first layer is a polybutene oil.
43 . The laminate according to claim 42 , wherein the plasticizing oil of the first layer is a polyisobutylene oil.
44 . The laminate according to claim 34 , wherein the plasticizing system of the first layer comprises from 2 to 30 phr of hydrocarbon resin.
45 . The laminate according to claim 44 , wherein the plasticizing system of the first layer comprises from 5 to 20 phr of hydrocarbon resin.
46 . The laminate according to claim 34 , wherein the hydrocarbon resin of the first layer is selected from the group consisting of cyclopentadiene or dicyclopentadiene homopolymer or copolymer resins, terpene homopolymer or copolymer resins, terpene/phenol homopolymer or copolymer resins, C5 fraction homopolymer or copolymer resins, C9 fraction homopolymer or copolymer resins, α-methylstyrene homopolymer or copolymer resins and mixtures thereof.
47 . The laminate according to claim 46 , wherein the hydrocarbon resin of the first layer is selected from the group consisting of copolymer resins of two different vinylaromatic monomers, (D)CPD/vinylaromatic, (D)CPD/terpene copolymer resins, (D)CPD/C5 fraction copolymer resins, (D)CPD/C5 fraction copolymer resins, (D)CPD/C9 fraction copolymer resins, terpene/vinylaromatic copolymer resins, terpene/phenol copolymer resins, C5 fraction/vinylaromatic copolymer resins and mixtures thereof.
48 . The laminate according to claim 47 , wherein the hydrocarbon resin of the first layer is selected from the group consisting of (D)CPD homopolymer resins, (D)CPD/styrene copolymer resins, polylimonene resins, limonene/styrene copolymer resins, limonene/D(CPD) copolymer resins, C5 fraction/styrene copolymer resins, C5 fraction/C9 fraction copolymer resins, styrene/α-methylstyrene copolymer resins and mixtures thereof.
49 . The laminate according to claim 48 , wherein the hydrocarbon resin of the first layer is a styrene/α-methylstyrene copolymer resin.
50 . The laminate according to claim 34 , wherein the total content of plasticizer is within a range extending from 5 to 45 phr.
51 . The laminate according to claim 50 , wherein the total content of plasticizer is within a range extending from 10 to 35 phr.
52 . The laminate according to claim 34 , wherein the first layer additionally comprises a platy filler.
53 . The laminate according to claim 34 , wherein the first layer does not comprise a crosslinking system.
54 . The laminate according to claim 34 , wherein the elastomer blocks of the at least one thermoplastic styrene elastomer of the second layer are chosen from elastomers having a glass transition temperature of less than 25° C.
55 . The laminate according to claim 34 , wherein the elastomer blocks of the at least one thermoplastic styrene elastomer of the second layer are selected from the group consisting of ethylene elastomers, diene elastomers and mixtures thereof.
56 . The laminate according to claim 55 , wherein the elastomer blocks of the at least one thermoplastic styrene elastomer of the second layer are chosen from ethylene elastomers.
57 . The laminate according to claim 55 , wherein the elastomer blocks of the at least one thermoplastic styrene elastomer of the second layer are chosen from diene elastomers.
58 . The laminate according to claim 34 , wherein the at least one thermoplastic styrene elastomer of the second layer comprises between 5% and 50% by weight of styrene.
59 . The laminate according to claim 34 , wherein the at least one thermoplastic styrene elastomer of the second layer is selected from the group consisting of styrene/ethylene/butylene (SEB), styrene/ethylene/propylene (SEP), styrene/ethylene/ethylene/propylene (SEEP), styrene/ethylene/butylene/styrene (SEBS), styrene/ethylene/propylene/styrene (SEPS), styrene/ethylene/ethylene/propylene/styrene (SEEPS), styrene/isobutylene (SIB), styrene/isobutylene/styrene (SIBS), styrene/butadiene (SB), styrene/isoprene (SI), styrene/butadiene/isoprene (SBI), styrene/butadiene/styrene (SBS), styrene/isoprene/styrene (SIS), styrene/butadiene/isoprene/styrene (SBIS), styrene/butadiene/butylene (SBB) and styrene/butadiene/butylene/styrene (SBBS) copolymer thermoplastic elastomers and mixtures thereof.
60 . The laminate according to claim 34 , wherein the content of the at least one thermoplastic styrene elastomer of the second layer is within a range extending from 5 to 45 phr.
61 . The laminate according to claim 60 , wherein the content of the at least one thermoplastic styrene elastomer of the second layer is within a range extending from 10 to 40 phr.
62 . The laminate according to claim 34 , wherein the at least one diene elastomer of the second layer is selected from the group consisting of essentially unsaturated diene elastomers and mixtures thereof.
63 . The laminate according to claim 62 , wherein the at least one diene elastomer of the second layer is selected from the group consisting of the homopolymers obtained by polymerization of a conjugated diene monomer having from 4 to 12 carbon atoms, the copolymers obtained by copolymerization of one or more conjugated dienes with one another or with one or more vinylaromatic compounds having from 8 to 20 carbon atoms, and mixtures thereof.
64 . The laminate according to claim 63 , wherein the at least one diene elastomer of the second layer is selected from the group consisting of polybutadienes, synthetic polyisoprenes, natural rubber, butadiene copolymers, isoprene copolymers and mixtures thereof.
65 . The laminate according to claim 34 , wherein the second layer further comprises a reinforcing filler.
66 . The laminate according to claim 65 , wherein the reinforcing filler of the second layer is carbon black and/or silica.
67 . The laminate according to claim 66 , wherein carbon black is the predominant reinforcing filler of the second layer.
68 . A tire comprising a laminate according to claim 34 .
69 . A pneumatic object comprising a laminate according to claim 34 .