A liquid crystal comb polymer of potential interest for electro-optical applications has been synthesized and characterized. The polymer has a polyacrylamide main chain and two different types of side group, built up of 4'-undecanoyloxy-4-cyanobiphenyl groups (68 mol%) and of shorter aliphatic groups (32 mol%). The two types of side group occur randomly along the polymer's main chain. The preparation steps and the liquid crystalline structure of the resulting copolymer are compared with those of a homopolymer whose side groups ( built up of 4'-undecanoyloxy-4-cyanobiphenyl groups) are all identical. X-ray diffraction shows that the polymers display different mesophases over different temperature ranges. However, the homopolymer exhibits two smectic phases (SmC(2) and SmA(2)), while the new copolymer exhibits a SmC(2) phase and a nematic mesophase at higher temperature. The mesophase thermal stability of the copolymer is significantly lower than that of the homopolymer.
Liquid crystal comb polymer with polar mesogenic and aliphatic side groups - I. Preparation and structural properties / B., Gallot; Allia, PAOLO MARIA EUGENIO ICILIO; P., Taverna; L., Trossi; C., Cucinelli; S., Ponti. - In: LIQUID CRYSTALS. - ISSN 0267-8292. - 29:(2002), pp. 397-404. [10.1080/02678290110104603]
Liquid crystal comb polymer with polar mesogenic and aliphatic side groups - I. Preparation and structural properties
ALLIA, PAOLO MARIA EUGENIO ICILIO;
2002
Abstract
A liquid crystal comb polymer of potential interest for electro-optical applications has been synthesized and characterized. The polymer has a polyacrylamide main chain and two different types of side group, built up of 4'-undecanoyloxy-4-cyanobiphenyl groups (68 mol%) and of shorter aliphatic groups (32 mol%). The two types of side group occur randomly along the polymer's main chain. The preparation steps and the liquid crystalline structure of the resulting copolymer are compared with those of a homopolymer whose side groups ( built up of 4'-undecanoyloxy-4-cyanobiphenyl groups) are all identical. X-ray diffraction shows that the polymers display different mesophases over different temperature ranges. However, the homopolymer exhibits two smectic phases (SmC(2) and SmA(2)), while the new copolymer exhibits a SmC(2) phase and a nematic mesophase at higher temperature. The mesophase thermal stability of the copolymer is significantly lower than that of the homopolymer.Pubblicazioni consigliate
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https://hdl.handle.net/11583/2498075
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