Abstract: Pneumatic tires having an improved steering response have a tread portion which comprises a blend of a base elastomer and, as a steering response substance, a polymer of an unsaturated compound selected from methacrylic acid, acrylic acid and lower alkyl esters thereof. The steering response substance is preferably a graft copolymer of polyisoprene and methylmethacrylate. A preferred amount of the steering response substance is in the range from 5 to 60% by weight of the total of the base elastomer and the steering response substance.

Abstract: A substitute ground surface material comprising sand coated or treated with a binder comprising a free flowing extender oil with a viscosity transition below -5.degree. F., with a synthetic polymeric material such as styrene-butadiene-styrene co-polymer dissolved or dispersed in the oil. The binder comprises approximately 2% of the material which is an inert, discreet material permanently capable of being raked when laid in a layer upon a substrate. The material is laid on a suitable porous base to form a sports surface for a horse running track or the like.

Abstract: Pneumatic tires having an improved steering response have a tread portion which comprises an elastomeric composition containing a long chain hydroxy fatty acid or a derivative thereof, or an inter-condensed or intracondensed form thereof. The hydroxy fatty acid can be a saturated monocarboxylic acid having:(a) 9 to 25 (for example 13 to 17 and especially 15, 16, or 17) carbon atoms as well as the carbon atom of the carboxylic acid group; and(b) 1 to 6 (for example 2, 3 or 4) hydroxy groups.Suitable compounds are di- and tri-hydroxy palmitic and stearic acids. The invention is concerned particularly with the use of shellac as the hydroxy fatty acid compound.

Abstract: There are disclosed copolymers of aromatic vinyl compounds, e.g., styrene, and conjugated diolefins, e.g., butadiene, possessing a differential content of the aromatic vinyl compound such that in at least one of the end portions of the copolymer the differential content shows a sharp and substantial increase in the direction of the outer extremity of the end portion. Preferred compolymers are styrene-butadiene copolymers having a vinyl content of at least 30%. In special embodiments, the copolymer have a styrene content changing in a portion of no more than 5% of the copolymer chain from a first value to a second value, the second value being at least 25 percentage points greater than the first value, and the portion is present within a 10% terminal portion of the copolymer. The copolymers are useful in the tread portions of tires as tires containing such copolymers in the tread composition have improved rolling resistance and/or grip on wet road surfaces.

Abstract: There is disclosed copolymers of aromatic vinyl compounds, e.g., styrene, and conjugated diolefins, e.g., butadiene, possessing a differential content of the aromatic vinyl compound such that in at least one of the end portions of the copolymer the differential content shows a sharp and substantial increase in the direction of the outer extremity of the end portion. Preferred copolymers are styrene-butadiene copolymers having a vinyl content of at least 30%. In special embodiments, the copolymers have a styrene content changing in a portion of no more than 5% of the copolymer chain from a first value to a second value, the second value being at least 25 percentage points greater than the first value, and the portion is present within a 10% terminal portion of the copolymer. The copolymers are useful in the tread portions of tires as tires containing such copolymers in the tread composition have improved rolling resistance and/or grip on wet road surfaces.

Abstract: Tires having good grip on wet road surfaces and low frictional resistance to rolling on the road surface have treads formed from vulcanisates of elastomer compositions comprising a major component consisting of one or more polymers having a glass transition temperature (Tg) of minus 50.degree. C. or lower temperature, and a minor component consisting of one or more polymers having a glass transition temperature of ambient temperature or higher temperature. The major component can consist of one or more rubbery polymers selected from natural rubbers, polybutadienes synthetic polyisoprenes and rubbery styrene-butadiene copolymers; and the minor component can consist of a resinous styrene-butadiene co-polymer.

Abstract: Tires having good grip on wet road surfaces and low frictional resistance to rolling on the road surface have treads formed from vulcanizates of elastomer compositions comprising one or more polymers having a glass transition temperature (Tg) of minus 50.degree. or lower blended with a non-cross-linking polymer or heavy oil. Suitable non-cross-linking polymers are polyisobutylenes, especially ones having a molecular weight of 1.06 to 1.44 million which are very effective with natural rubber, polybutadienes and/or styrene-butadiene copolymers as the low Tg polymers.