Golf balls containing interpenetrating polymer networks
The present invention is directed to a golf ball that contains an interpenetrating polymer network, or IPN, including at least two polymeric components. These IPNs may be present in any golf ball layer, although in an intermediate or cover layer in one preferred embodiment. The present invention is also directed to methods of forming a golf ball containing an IPN in one or more of the layers.
1. A golf ball comprising a core, a cover, and an intermediate layer, wherein the cover layer comprises a non-ionomeric interpenetrating polymer network formed from a first polymeric component comprising polyurethane and a second polymeric component comprises polybutadienediacrylate copolymer, wherein the IPN exhibits a ΔT g between the first and the second polymeric components at least about 5% less than the ΔT g between a polymer blend comprising the same polymeric components, and wherein at least one of first and second polymeric components is a crystallizable polymeric component that exhibits an area under a melting endotherm of at least about 2% less than the area under the melting endotherm of a homopolymer of the same crystallizable polymeric component.
2. The golf ball of claim 1 , wherein the crystallizable polymeric component exhibits an area under a melting endotherm of at least about 10% less than the area under the melting endotherm of the homopolymer of the same crystallizable polymeric component.
3. The golf ball of claim 1 , wherein the polyurethane comprises the reaction product of a urethane prepolymer and a hydroxy-terminated curing agent.
4. The golf ball of claim 1 , wherein the polybutadienediacrylate copolymer comprises the reaction product of a butadiene monomer or a polybutadiene resin, a diacrylate crosslinking agent, and an initiator.
5. The golf ball of claim 4 , wherein the initiator comprises peroxide.
6. The golf ball of claim 1 , wherein the IPN exhibits only one observable T g for the first and second polymeric components.
7. The golf ball of claim 1 , wherein the IPN exhibits a ΔT g between any the first and second polymeric components at least about 20% less than the ΔT g between a polymer blend comprising the same polymeric components.
8. The golf ball of claim 7 , wherein the IPN exhibits only one observable T g for the first and second polymeric components.
9. The golf ball of claim 7 , wherein the IPN exhibits a ΔT g between the first and second polymeric components at least about 50% less than the ΔT g between a polymer blend comprising the same polymeric components.
10. The golf ball of claim 9 , wherein the IPN exhibits only one observable T g for the first and second polymeric components.