Kinetically controlled phase transitions in LC polymers. I. Isokinetic range crossover for the Sm B-Sm H transition in a side-chain polysiloxane

The kinetics of smectic‐phase formation in a siloxane copolymer, as compared with the crystallization of the relating homopolymer, was studied by the Avrami analysis of DSC data. A crossover from the diffusion‐controlled kinetics (the Avrami exponent k ∼0.35) to the two‐dimensional free‐growth mode (k ∼1.5) with increasing temperature was detected. The influence of the annealing temperature on the sequence of mesophases, transition temperatures, and enthalpies of the polymers was also investigated. © 2001 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 39: 1055–1060, 2001