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

• Published in: Journal of polymer science. Part B, Polymer physics Vol. 39; no. 10; pp. 1055 - 1060
• Main Author: Kozlovsky, Mikhail V.
• Format: Journal Article
• Language: English
• Published: New York John Wiley & Sons, Inc 15-05-2001; Wiley
• Subjects: Applied sciences; Exact sciences and technology; Inorganic and organomineral polymers; kinetics; liquid crystals; phase transitions; Physicochemistry of polymers; polysiloxanes; Properties and characterization; side-chain polymers; Side chain; Biphenyl derivatives; Thermal history; Liquid crystal polymers; Thermotropic state; Smectic smectic transformation; Kinetics; Experimental study; Dimethylsiloxane copolymer; Siloxane copolymer; Siloxane polymer; Phase transitions
• ISSN: 0887-6266; 1099-0488
• DOI: 10.1002/polb.1082

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