Part II: Elastomeric Condensation Block Copolymers

copolymero. It has been shown by Wittbecker and coworkers [5] that a crystalline high-melting polyamide such as 6-10 can be converted to an elastomeric polymer by substituting part of the amide hydrogens with alkyl groups. Table I illustrates how profoundly physical properties of a 6-10 polyamide fiber change when half of the amide hydrogens in the polymer ’ are substituted with isobutyl groups. Breaking elongation changes from 25% to 400%, or 16-fold. Furthermore, much of this elongation is reversible. The drop in melting point demonstrates how importantly hydrogen bonds function in tying ad-