Abstract: The present invention is directed to an airspring having an airsleeve comprising an elastomeric liner; a reinforcing layer overlaying the liner; and a colorable elastomeric cover overlaying the reinforcing layer; the cover comprising: 100 parts by weight of elastomer comprising from about 30 to about 50 parts by weight of natural rubber, from about 10 to about 30 parts by weight of polybutadiene, and from about 30 to about 50 parts by weight of ethylene propylene diene terpolymer (EPDM); from about 20 to about 60 parts by weight, per 100 parts by weight of elastomer, of silica; and from about 1 to about 10 parts by weight, per 100 parts by weight of elastomer, of an organosilane polysulfide.

Abstract: In a tire having a tread with cap/base construction, a regulated amount of partially crosslinked natural rubber in a tire tread compound increases the uncured ("green") stiffness, tensile strength and tear resistance of a green compound used for the base without adversely affecting physical properties of the tread after it is cured. Such green stiffness is particularly useful in the construction of a tread for a pneumatic tire, which tread is of cap/base construction because stiffness provides requisite dimensional stability of both cap and base (in the tread) during the curing of the tire. The amount of partially crosslinked natural rubber used in a tread compound depends upon the extent of crosslinking in the natural rubber, the non-crosslinked remainder being virgin latex.

Abstract: Expandable bladders for use in curing presses for hydrocarbon rubbers, such as pneumatic tires, are a crosslinked elastomer composition comprising isobutylene repeat units and including a fluorinated ethylene polymer added in particulate form and thereafter dispersed throughout the bladder. These fluorinated ethylene polymer may or may not form fibers. The bladders may further comprise graphite. A preferred isobutylene elastomer is a brominated copolymer of from 80 to 99 weight percent isobutylene and from 1 to 20 weight percent paramethylstyrene. The bladders have enhanced lubricity, reduced adhesion to cured tire innerliners, better resistance to cracking during flexing, and have lower tension set than similar compositions without fluorinated ethylene polymers. The above enhancements allow hydrocarbon rubbers such as tires to be molded with fewer defects caused by abraded or deformed bladders. They also enhance the useful life of the bladder reducing the cost of tire curing.