The use of a low molecular weight farnesene, poly(farnesene), and farnesene copolymer in a golf ball is disclosed herein. In a core, low molecular weight farnesene, poly(farnesene) or farnesene copolymer is blended with 1,4 polybutadiene or a polyalkenamer. In a mantle layer, low molecular weight farnesene, poly(farnesene), and/or farnesene copolymer can be blended with non- or partially neutralized copolymeric or terpolymeric ionomer(s). In a cover, low molecular weight farnesene, poly(farnesene), and farnesene copolymer can be blended with highly neutralized ionomer.

Multi-piece golf balls having a multi-layered solid core and multi-layered cover are provided.

Golf ball having CoR of at least 0.700 and compression of at least 50 and comprising a layer of a mixture of thermoset or thermoplastic composition and a plurality of conductive nanoshelled structures such as conductive hollow nanoshells and/or nanorice particles. Conductive nanoshelled structures may be included in amount of from about 2 wt % to greater than 50 wt. % of total weight of mixture. Diameter of each conductive nano shelled structure at widest cross-section may be up to 1000 nm. Each conductive hollow nanoshell may have shell thickness to longitudinal diameter ratio of from about 1:3 to about 1:100. Each nanorice particle may have longitudinal diameter of up to 1000 nm. Shell thickness can be from 1 nm to 100 nm and may be controlled. A layer consisting of mixture may have specific gravity that differs from specific gravity of a layer consisting of the thermoset or thermoplastic composition portion of mixture.

Multi-layered golf balls having a core, intermediate layer, and cover are provided. The ball includes a non-foamed inner core (center) made of a thermoplastic or thermoset composition such as polybutadiene rubber. An intermediate layer comprising a foamed composition, such as polyurethane foam, is disposed about the inner core. The foamed intermediate layer may have a specific gravity gradient within the layer, wherein the outer surface specific gravity is greater than the midpoint specific gravity. Ball constructions having two intermediate layers, wherein at least one layer is a foamed layer can be made. A cover having at least one layer is disposed about the intermediate layer.

Multi-piece golf balls having a multi-layered solid core and multi-layered cover are provided.

Multi-layered golf balls containing a dual-core structure are provided. The core structure includes an inner core (center) made from a foam or metal-containing composition, or it has a hollow shell construction, and the outer core layer is made of a thermoplastic composition. Preferably, the thermoplastic composition comprises: a) ethylene acid copolymer, b) plasticizer, and c) cation source. A fatty acid ester such as ethyl oleate is preferably used as the plasticizer. The core assembly preferably has a positive hardness gradient extending across the entire assembly. The core structure and resulting ball have relatively good resiliency at given compressions.

Golf balls comprising a core having at least one layer and a cover having at least one layer are provided. At least one of the layers is made from a thermoplastic composition preferably comprising a telechelic ionomer derived from alkyl-cis-cyclooctene and cis-cyclooctene. The telechelic ionomer composition also may be used to form intermediate layers. Blends of telechelic ionomers and polybutadiene rubbers or ethylene acid copolymers can be prepared. The telechelic ionomer compositions can be used to make a cover layer having good impact durability and shear resistance and that also helps provide the ball with high resiliency.

The present invention provides a golf ball comprising an inner core and an outer cover layer, wherein at least one of the inner core and outer cover layer is formed from a thermoplastic polyurethane ionomer.

Multi-piece golf balls having a multi-layered solid core and multi-layered cover are provided.

An object of the present invention is to provide a rubber composition from which a crosslinked rubber molded product excellent in the resilience performance can be obtained. The present invention provides a rubber composition containing (a) a base rubber, (b) a co-crosslinking agent and (c) a crosslinking initiator, wherein (b) the co-crosslinking agent contains a complex represented by a general formula (1).
((RCOO).sub.8M.sub.5(OH).sub.2).sub.n(1) [In the formula (1), M is a metal atom, R is a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms or an alkynyl group having 2 to 18 carbon atoms, and n is an integer of 1 or more. A plurality of R and M may be identical to or different from each other. At least one of R is the alkenyl group having 2 to 18 carbon atoms or the alkynyl group having 2 to 18 carbon atoms.]