Golf ball compositions

Abstract

Disclosed herein are hard and flexible compositions, i.e., compositions which have a flexural modulus that is less than the value that is expected based on the composition's hardness. The compositions preferably have a hardness/modulus relationship represented by the formula H ≧11.889 Ln( M )+47, where H is the hardness of the composition, in JIS-C, and M is the flexural modulus of the composition, in ksi; or a softness/stiffness relationship represented by the formula if M <110, then H ≧8.5218 Ln( M )+32.5 if M≧110, then H≧72.5, where H is the hardness of the composition, in Shore D, and M is the flexural modulus of the composition, in ksi. The compositions preferably comprise an ionomer having an acid content of 9 wt % or less and a high level of fatty acid.

1 . A golf ball comprising at least one layer formed from a thermoplastic composition, the thermoplastic composition comprising:
 (a) an E/X- or E/X/Y-type copolymer or metal salt thereof, wherein E is ethylene, X is an α,β-unsaturated carboxylic acid present in an amount of 9 wt % or less, based on the total weight of the copolymer, and Y is an acrylate selected from alkyl acrylates and aryl acrylates present in an amount of from 0 wt % to 50 wt %, based on the total weight of the copolymer;   (b) a fatty acid or metal salt thereof present in an amount of 20 wt % or greater, based on the total weight of the thermoplastic composition; and   (c) optionally an additional cation source;   wherein at least 50% of the acid groups present in the thermoplastic composition are neutralized; and   wherein the thermoplastic composition has a JIS-C hardness (H) and a flexural modulus in ksi (M) wherein H≧11.889 Ln(M)+47.   
     
     
         2 . The golf ball of  claim 1 , wherein H≧11.889 Ln(M)+49. 
     
     
         3 . The golf ball of  claim 1 , wherein H≧65. 
     
     
         4 . The golf ball of  claim 1 , wherein X is present in an amount of 7 wt % or less, based on the total weight of the copolymer or metal salt thereof. 
     
     
         5 . The golf ball of  claim 1 , wherein X is present in an amount of 6 wt % or less, based on the total weight of the copolymer or metal salt thereof. 
     
     
         6 . The golf ball of  claim 1 , wherein the fatty acid or metal salt thereof is present in an amount of 30 wt % or greater, based on the total weight of the thermoplastic composition. 
     
     
         7 . The golf ball of  claim 1 , wherein the fatty acid or metal salt thereof is present in an amount of 35 wt % or greater, based on the total weight of the thermoplastic composition. 
     
     
         8 . The golf ball of  claim 1 , wherein 70% or greater of the acid groups present in the thermoplastic composition are neutralized. 
     
     
         9 . The golf ball of  claim 1 , wherein 90% or greater of the acid groups present in the thermoplastic composition are neutralized. 
     
     
         10 . The golf ball of  claim 1 , wherein 100% of the acid groups present in the thermoplastic composition are neutralized. 
     
     
         11 . A golf ball comprising at least one layer formed from a thermoplastic composition, the thermoplastic composition comprising:
 (a) an E/X- or E/X/Y-type copolymer or metal salt thereof, wherein E is ethylene, X is an α,β-unsaturated carboxylic acid present in an amount of less than 9 wt %, based on the total weight of the copolymer, and Y is an acrylate selected from alkyl acrylates and aryl acrylates present in an amount of from 0 wt % to 50 wt %, based on the total weight of the copolymer;   (b) a fatty acid or metal salt thereof present in an amount of 35 wt % or greater, based on the total weight of the thermoplastic composition; and   (c) optionally an additional cation source;   wherein at least 50% of the acid groups present in the thermoplastic composition are neutralized; and   wherein the thermoplastic composition has a JIS-C hardness (H) and a flexural modulus in ksi (M) wherein H≧11.889 Ln(M)+47.   
     
     
         12 . The golf ball of  claim 11 , wherein H≧11.889 Ln(M)+49. 
     
     
         13 . The golf ball of  claim 11 , wherein H≧65. 
     
     
         14 . The golf ball of  claim 11 , wherein 70% or greater of the acid groups present in the thermoplastic composition are neutralized. 
     
     
         15 . The golf ball of  claim 11 , wherein 90% or greater of the acid groups present in the thermoplastic composition are neutralized. 
     
     
         16 . The golf ball of  claim 11 , wherein 100% of the acid groups present in the thermoplastic composition are neutralized. 
     
     
         17 . A golf ball comprising at least one layer formed from a thermoplastic composition, the thermoplastic composition comprising:
 (a) an E/X- or E/X/Y-type copolymer or metal salt thereof, wherein E is ethylene, X is an α,β-unsaturated carboxylic acid present in an amount of 7 wt % or less, based on the total weight of the copolymer, and Y is an acrylate selected from alkyl acrylates and aryl acrylates present in an amount of from 0 wt % to 50 wt %, based on the total weight of the copolymer;   (b) a fatty acid or metal salt thereof present in an amount of 35 wt % or greater, based on the total weight of the thermoplastic composition; and   (c) optionally an additional cation source;   wherein at least 50% of the acid groups present in the thermoplastic composition are neutralized; and   wherein the thermoplastic composition has a JIS-C hardness (H) and a flexural modulus in ksi (M) wherein H≧11.889 Ln(M)+47.   
     
     
         18 . The golf ball of  claim 17 , wherein H≧11.889 Ln(M)+49. 
     
     
         19 . The golf ball of  claim 17 , wherein H≧65. 
     
     
         20 . The golf ball of  claim 17 , wherein 100% of the acid groups present in the thermoplastic composition are neutralized.