Water-dispersible polyurethane polymer

A coating composition comprising:

• an aqueous carrier;
• and
• a polyurethane polymer comprising:
• a plurality of urethane linkages;
• a plurality of cycloaliphatic groups that constitute at least about 4 percent by weight of the polyurethane polymer, based on a total dry weight of the polyurethane polymer;
• a plurality of functional groups configured to render the polyurethane polymer at least partially dispersible in the aqueous carrier;
• and
• a plurality of ethylenically-unsaturated fatty acid groups that constitute at least about 15 percent by weight of the polyurethane polymer, based on the total dry weight of the polyurethane polymer.

A method for forming a polyurethane polymer, the method comprising:

• forming a prepolymer comprising:
• at least one cycloaliphatic group comprising a structure X—Z—X, wherein:
• Z is an aliphatic ring structure;
• each X is a group independently selected from an ester group, an ether group, an amide group, a carbonate group, hydrogen, or CRn, where R is independently selected from hydrogen, a halogen, oxygen, nitrogen, an organic group, or a combination thereof and n is 0, 1, or 2;
• and
• at least one of the X groups is a divalent linkage group that attaches the at least one cycloaliphatic group to another portion of the prepolymer;
• at least one terminal or pendant isocyanate group;
• a plurality of air-curable ethylenically unsaturated groups;
• and
• a plurality of salt-forming groups;
• and
• neutralizing the at least a portion of the salt-forming groups to form a salt group on the prepolymer.