The dynamics of the helix‐coil transition in poly‐α, L‐glutamic acid

Temperature jump measurements employing optical rotation to follow transients show an upper limit of 10μsec. on the half time of the helix‐random coil relaxation in poly‐α, L ‐glutamic acid. No relaxations are observed under conditions where the polymer exists in completely helical or completely random coil form. Assuming that the helix‐coil transition can be described kinetically as a pure growth process, expressions for the relaxation time are derived for three special cases. A comparison is made between the rate of the helix‐coil transition and the rate of imide proton exchange.