Polymerization for Fiber Use. More than 95% of all polyamide fibers are made, by a hydrolytic polymerization rechnique The polycaproamide process involves three steps (see Reis. 143-146.149-131,455, and 456) ; 1. Initiation and addition: As a practical matter. once one molecule has formed aminocaproic acid. by hydrolysis with water. caprolactam successively adds to this ehain until a molecular weight between 8.000 (DP 71) and 14.000 (DP 124) is attained Thus. the hydroiysis portion of the initiation step is from 1 part in 70 to 1 pert in 124 The reaction is carried out under pressure and generally more than 95% of the monomer which will react under equilibrium conditions is formed into these short chains er ring opening. addition, and condensation reactions may be regarded as concurrent in his stage