The present invention is directed to a pneumatic tire comprising a radially outer circumferential rubber tread disposed on a supporting carcass, an inner liner rubber layer radially inwardly disposed on the supporting carcass, and a sealant layer adhered to and disposed inwardly of the rubber inner liner layer as a radially inner surface of the tire, wherein the sealant layer comprises 100 parts by weight of elastomer comprising 5 to 10 parts by weight, per 100 parts by weight of elastomer (phr) of butyl rubber, 10 to 25 phr of bromobutyl rubber, and 65 to 85 phr of polybutene: and from 0.05 to 2 phr of a polymeric amine.

A method of selectively controlling the self-sealing ability of a tyre obtained by application of a sealing assembly on a drum and subsequent formation thereon of a precursor of a green tyre inclusive of liner and carcass, followed by shaping, curing and molding. The sealing assembly includes: a self-supporting thermoplastic film of polyamide or polyester and a layer of sealing material possessing viscoelasticity and stickiness features, which is associated with and supported by the self-supporting thermoplastic film. The sealing assembly is easily puncturable by a sharp-pointed element while it maintains such a deformability and stickiness that it helps in the transfer of the sealing material during ejection of the sharp-pointed element and limits the transferred material amount to such an extent that holes bigger than a predetermined value are not sealed.

A method of forming an implant includes providing a preformed shell formed from at least one cured elastomeric layer. The shell includes an outer surface, an inner surface, and an opening for accessing an interior volume of the shell. The method further includes expanding the shell to an expanded state, in which the interior volume is greater than the interior volume of the shell at a time of forming the shell and forming an inner zone having at least one inner elastomeric layer on at least a portion of the inner surface of the shell, while the shell is in the expanded state, thereby forming a multi-zone shell. The method further includes reducing the interior volume of the multi-zone shell, thereby contracting the at least one inner elastomeric layer of the inner zone and causing texturing of the at least one inner elastomeric layer.