A thermoplastic golf ball material is made by combining and reacting (a) an unneutralized copolymer of ethylene and at least one of acrylic acid and methacrylic acid, which has from about 5 to about 12 percent by weight acid monomer; (b) a metallocene-catalyzed copolymer of ethylene and octene; (c) an unsaturated fatty acid; and (d) a metal cation in an amount sufficient to neutralize from about 65 to about 90% of the acid groups, to produce an ionomeric thermoplastic material. The ionomeric thermoplastic material may be used in a core, a cover, or a layer between a core and a cover of a golf ball.
