Preparation and characterization of side-chain liquid crystalline polymer thin films aligned on PTFE friction-transferred layers

• Published in: Polymer (Guilford) Vol. 39; no. 15; pp. 3545 - 3550
• Main Authors: Wittmann, J.C., Meyer, S., Damman, P., Dosière, M., Schmidt, H-W.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.07.1998; Elsevier
• Subjects: Applied sciences; Exact sciences and technology; Organic polymers; Physicochemistry of polymers; Properties and characterization; PTFE; side-chain liquid crystal polymer; smectic layers; Structure, morphology and analysis; PTFE; smectic layers; side-chain liquid crystal polymer; Annealing; Tetrafluoroethylene polymer; Thermotropic state; Chlorine containing copolymer; Smectic state; Experimental study; Thin film; Structure processing relationship; Alignment; Side chain; Molecular orientation; Oriented polymer; Acrylate polymer; Order parameter; Liquid crystal polymers; Acrylate copolymer; Oriented copolymer
• ISSN: 0032-3861; 1873-2291
• DOI: 10.1016/S0032-3861(97)10104-5

Annealing of a side-chain LC polymer (SC-LCP) and a fluorescent dye containing copolymer deposited on friction-transferred PTFE substrates is found to yield macroscopically aligned glassy films. The results obtained by electron diffraction, u.v.-visible and FTi.r. spectroscopy clearly demonstrate that the mesogenic side-groups as well as the fluorescence dye orient with their long axes parallel to the PTFE chain axis. Thus, the SC-LCP aligned thin films adopt a near perfect bookshelf geometry in which the smectic layers are oriented edge-on and perpendicular to the alignment direction. The order parameter P2 increases from 0.60 to as high as 0.85 when the annealing temperature in the smectic mesophase approaches the smectic to nematic phase transition temperature.