A tire sealant layer comprising a rubber portion having an upper surface and a lower surface, the rubber portion comprising a mixture of i. 100 parts of at least one rubber selected from the group consisting of butyl rubber which is optionally halogenated, natural rubber, polyisoprene, polybutadiene rubber, styrene-butadiene rubber, styrene-butadiene-isoprene rubber, isoprene-butadiene rubber, polychloroprene rubber, EPDM, nitrile rubber, polyisobutylene, and combinations thereof, wherein at least 60 parts of the 100 parts of rubber comprise butyl rubber, halogenated butyl rubber, EPDM, or a combination thereof; ii. 90-210 phr of at least one tackifier, wherein up to 200 parts of the at least one tackifier comprise polybutene; iii. optionally one or more extenders in a total amount of no more than 55 phr; iv. optionally at least one hydroscopic substance in an amount of 0.5 to 10 phr; and v. a cure package; and a barrier layer upon the lower surface of the rubber portion wherein the barrier layer has an inner surface facing towards the rubber portion and an outer surface facing away from the rubber portion, wherein the barrier layer is resistant to migration of oil or tackifier, comprises a metal foil or a polymeric film, has a thickness of 0.01 to 0.3 mm, and the polymeric film, when present, is selected from the group consisting of polytetrafluoroethylene (PTFE), nylon, polyethylene terephthalate, polyethylene naphthalate, fluoroelastomers, polyphenylene sulfide, polyvinylidene fluoride (PVDF), ultrahigh molecular weight polyethylene (UHMW-PE), polyether ether ketone (PEEK), and combinations thereof, and wherein the sealant layer has a thickness of 2-8 mm. a rubber portion having an upper surface and a lower surface, the rubber portion comprising a mixture of i. 100 parts of at least one rubber selected from the group consisting of butyl rubber which is optionally halogenated, natural rubber, polyisoprene, polybutadiene rubber, styrene-butadiene rubber, styrene-butadiene-isoprene rubber, isoprene-butadiene rubber, polychloroprene rubber, EPDM, nitrile rubber, polyisobutylene, and combinations thereof, wherein at least 60 parts of the 100 parts of rubber comprise butyl rubber, halogenated butyl rubber, EPDM, or a combination thereof; ii. 90-210 phr of at least one tackifier, wherein up to 200 parts of the at least one tackifier comprise polybutene; iii. optionally one or more extenders in a total amount of no more than 55 phr; iv. optionally at least one hydroscopic substance in an amount of 0.5 to 10 phr; and v. a cure package; and i. 100 parts of at least one rubber selected from the group consisting of butyl rubber which is optionally halogenated, natural rubber, polyisoprene, polybutadiene rubber, styrene-butadiene rubber, styrene-butadiene-isoprene rubber, isoprene-butadiene rubber, polychloroprene rubber, EPDM, nitrile rubber, polyisobutylene, and combinations thereof, wherein at least 60 parts of the 100 parts of rubber comprise butyl rubber, halogenated butyl rubber, EPDM, or a combination thereof; ii. 90-210 phr of at least one tackifier, wherein up to 200 parts of the at least one tackifier comprise polybutene; iii. optionally one or more extenders in a total amount of no more than 55 phr; iv. optionally at least one hydroscopic substance in an amount of 0.5 to 10 phr; and v. a cure package; and a barrier layer upon the lower surface of the rubber portion wherein the barrier layer has an inner surface facing towards the rubber portion and an outer surface facing away from the rubber portion, wherein the barrier layer is resistant to migration of oil or tackifier, comprises a metal foil or a polymeric film, has a thickness of 0.01 to 0.3 mm, and the polymeric film, when present, is selected from the group consisting of polytetrafluoroethylene (PTFE), nylon, polyethylene terephthalate, polyethylene naphthalate, fluoroelastomers, polyphenylene sulfide, polyvinylidene fluoride (PVDF), ultrahigh molecular weight polyethylene (UHMW-PE), polyether ether ketone (PEEK), and combinations thereof, and wherein the sealant layer has a thickness of 2-8 mm.