The present disclosure relates to golf balls having components including intermediate layers and outer cover layers prepared from blends of polyamides mixed with one or more functional polymer modifiers. The functional polymer modifier incorporates a copolymer or a terpolymer having a glycidyl group, hydroxyl group, maleic anhydride group or carboxylic group, or a mixture of these. When used in golf ball covers or mantles, these materials exhibit improved impact durability when compared to analogous balls but having ionomeric- or polyurethane-based layers of similar hardness.
1. A golf ball comprising;
1) a unitary core,
2) an outer cover layer comprising a thermoset polyurethane or polyurea; and
3) three mantle layers, including an outer mantle layer immediately adjacent the outer cover layer,
wherein the outer mantle layer comprises a blend composition of;
(A) from about 50 to about 95 wt % (based on the combined weight of Components A and B) of a polyamide; and
(B) from about 5 to about 50 wt % (based on the combined weight of Components A and B) of one or more functional polymer modifiers selected from the group consisting of a copolymer having a glycidyl group, hydroxyl group, maleic anhydride group or carboxylic group, or a terpolymer having a glycidyl group, hydroxyl group, maleic anhydride group or carboxylic group, and mixtures thereof; and
wherein said blend composition has a flexural modulus of from about 5 to about 500 kpsi, a Shore D hardness of from about 25 to about 85, and a tensile elongation of at least about 20% and wherein one of the mantle layers other than the outer mantle layer comprises a polyalkenamer, and one of the mantle layers other than the outer mantle layer comprises a modified ionomer.
2. The golf ball of claim 1 wherein in said blend composition;
A) Component A is present in an amount of from about 55 to about 90 wt % (based on the combined weight of Components A and B) and comprises one or more aliphatic or cycloaliphatic polyamides; and
B) Component B is present in an amount of from about 10 to about 45 wt % (based on the combined weight of Components A and B) and comprises one or more maleic anhydride grafted polyolefins; and
wherein said blend composition has a flexural modulus of from about 15 to about 400 kpsi, a Shore D hardness of from about 30 to about 80, and a tensile elongation of at least about 40%.
3. The golf ball of claim 1 wherein in said blend composition;
A) Component A is present in an amount of from about 60 to about 85 wt % (based on the combined weight of Components A and B) and comprises the cycloaliphatic polyamide, BMACM 12, formed by equimolar mixing of (bis(methyl-para-aminocyclohexyl) methane) obtained by virtually equimolar mixing of BMACM and of dodecanedioic acid; and
B) Component B is present in an amount of from about 15 to about 40 wt % (based on the combined weight of Components A and B) and comprises one or more maleic anhydride grafted polyolefins selected from maleic anhydride-modified ethylene-propylene copolymer, maleic anhydride-modified ethylene-propylene-diene terpolymer, maleic anhydride-modified polyethylene, maleic anhydride-modified polypropylene, ethylene-ethylacrylate-maleic anhydride terpolymer, or maleic anhydride-indene-styrene-cumarone polymer;
wherein the blend composition has a flexural modulus of from about 200 to about 300 kpsi., a Shore D hardness of from about 35 to about 75, and a tensile elongation of at least about 80%.
4. The golf ball of claim 1 wherein said blend composition has a tensile strength of at least 4000 psi.
5. The golf ball of claim 3 wherein said blend composition has a tensile strength of at least 4000 psi.
6. The golf ball of claim 1 wherein said blend composition has a tensile strength of at least 4250 psi.
7. The golf ball of claim 1 wherein said blend composition has a tensile strength of at least 5000 psi.
8. The golf ball of claim 1 wherein Component A comprises a thermoplastic polyamide elastomer.
9. The golf ball of claim 1 wherein Component B comprises an αolefin.
10. The golf ball of claim 1 wherein the blend composition further comprises erucamide.
11. The golf ball of claim 1 wherein the blend composition comprises at least 60 wt % of all the ingredients of the outer mantle layer.
12. The golf ball of claim 3 wherein the blend composition comprises at least 60 wt % of all the ingredients of the outer mantle layer.
13. The golf ball of claim 1 wherein Component A comprises at least one cycloaliphatic polyamide and Component B comprises at least one maleic anhydride grafted polyolefin.