Thiophene-based photoresponsive mesogens

Chambers-Asman, D., 2007. Thiophene-based photoresponsive mesogens. PhD, Nottingham Trent University.

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Abstract

This thesis reports the synthesis, transition temperatures and structure-property relationships of a variety of thiophene-containing azobenzene esters derived from either 3-(2-thienyl)acrylic acid (Series I, IV, VI, VIII, X and XII) or 3-(3-thienyl)acrylic acid (Series II, V, VII, IX, XI and XIII) and appropriate fluoro- and non-fluoro-substituted 'azophenols', for potential use in photoresponsive applications. For comparative purposes, the non-heterocyclic cinnamate counterparts (Series III) were also prepared and are reported. All one hundred and thirty final esters are mesomorphic, exhibiting the nematic phase alone. The mesomorphic properties are dependent upon the disposition of the terminal thiophene moiety. In general 3-thienyl-substitution gives thermally more stable compounds than 2-thienyl-substitution. Influence of mono- (Series IV, V, VI and VII) and di- (Series VIII, IX, X, XI, XII and XIII) lateral fluoro-substitution on mesomorphic properties is investigated in detail Lateral fluorination lowers mesophase thermal stability and its extent is dependent upon the number and disposition of the lateral fluoro-substituents. Di-lateral fluorination across the long molecular axis is more detrimental to mesophase thermal stability than along the long molecular axis. UV-Vis steady state photoresponsive studies on Series I show that trans-cis photoisomerisation may be induced at 367 nm, with the reverse cis-trans isomerisation process occurring 434 nm.

Item Type:	Thesis
Creators:	Chambers-Asman, D.
Date:	2007
Rights:	This work is the intellectual property of the author, and may also be owned by the research sponsor(s) and/or Nottingham Trent University. You may copy up to 5% of this work for private study, or personal, non-commercial research. Any re-use of the information contained within this document should be fully referenced, quoting the author, title, university, degree level and pagination. Queries or requests for any other use, of if a more substantial copy is required, should be directed in the first instance to the author.
Divisions:	Schools > School of Science and Technology
Record created by:	EPrints Services
Date Added:	09 Oct 2015 09:34
Last Modified:	09 Oct 2015 09:34
URI:	https://irep.ntu.ac.uk/id/eprint/148

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