Cross-linked thermoplastic polyurethane/polyurea and method of making same

1. A method for forming a golf ball layer composed of a cross-linked thermoplastic polymer, the method comprising:

mixing a thermoplastic urethane based material and a monomeric diisocyanate to create a first mixture, the monomeric diisocynate comprising between 1% to 10% of the total mass of the first mixture;

mixing 4,4′ methylene-bis-(3-chloro-2,6-diethylaniline) and diethyl 2,4-toluenediamine to create a second mixture, wherein the 4,4′ methylene-bis-(3-chloro-2,6-diethylaniline) is 75% to 95% of the total mass of the second mixture and diethyl 2,4-toluenediamine is 25% to 5% of the total mass of the second mixture;

heating the first mixture to a temperature within the range of 250° F. to 550° F. to create a heated first mixture;

heating the second mixture to a temperature greater than the melting point of the second mixture and less than 225° F. to create a liquid second mixture having a volume;

injecting the heated first mixture into a barrel of an injection molding machine through a first opening;

injecting the liquid second mixture into the barrel of the injection molding machine in a plurality of dispensing shots of approximately equal amounts of the volume of the liquid second mixture during a predetermined time period;

injecting a reaction product into at least one injection mold cavity, the reaction product formed by the reaction of the heated first mixture and the liquid second mixture; and

forming a golf ball layer composed of the reaction product.