Methods to produce keratin elastomer, involving:(A)(1) reacting a diisocyanate with a blocking agent to form a diisocyanate with one —NCO group blocked by the blocking agent and one —NCO group unblocked,(2) reacting the diisocyanate with one —NCO group blocked by the blocking agent and one —NCO group unblocked with keratin at about 100° to about 120° C. to form keratin urethane with —NCO group functionality (i.e., with one —NCO group unblocked),(3) optionally reacting the keratin urethane with —NCO group functionality with a compound capable of reacting with the —NCO group(B) reacting a diisocyanate with keratin to form keratin elastomer or(C) reacting a monoisocyanate with keratin to form keratin elastomer.
