Liquid-crystalline azobenzene-containing ferrocene-based polymers: study on synthesis and properties of main-chain ferrocene-based polyesters with azobenzene in the side chain
2013 (English)In: Polymers for Advanced Technologies, ISSN 1042-7147, E-ISSN 1099-1581, Vol. 24, no 2, 181-190 p.Article in journal (Refereed) Published
Ferrocene-based polymers are characterized by their electrochemical activity, good redox properties, thermal, photochemical stability, and liquid crystallinity, and thus they have various applications in different fields. A comprehensive investigation on the synthesis and properties of three novel main-chain ferrocene-based polyesters with azobenzene in the side chain (MFPAS) was carried out. The main-chain ferrocene-based polyester, poly(N-phenyldiethanolamine 1,1'-ferrocene dicarboxylate (PPFD), was synthesized via the solution polycondensation reaction of 1,1'-ferrocenedicarbonyl chloride with phenyldiethanolamine (PDE). The novel MFPAS were synthesized via the post-polymerization azo-coupling reaction of PPFD with three different 4-substituted anilines including 4-nitroaniline, 4-aminobenzoic acid, and 4-aminobenzonitrile to produce 4-nitrophenylazo-functionalized-PPFD (PPFD-NT), 4-carboxyphenylazo-functionalized-PPFD (PPFD-CA), and 4-cyanophenylazo-functionalized-PPFD (PPFD-CN), respectively. All the synthesized polymers were characterized by 1H NMR spectroscopy, Fourier transform infrared spectroscopy, and UVvisible spectroscopy. In addition, powder X-ray diffraction patterns were measured for the synthesized polymers. The photoisomerization of the MFPAS was studied. The thermal properties of the MFPAS were studied using thermogravimetric analysis and differential scanning calorimetry. PPFD-CA and PPFD-CN were found to be more thermally stable than PPFD-NT. Finally, the liquid-crystalline properties of PPFD and the MFPAS were examined using polarized optical microscope. It was found that all the polymers possessed nematic phases and exhibited textures with schlieren disclinations.
Place, publisher, year, edition, pages
2013. Vol. 24, no 2, 181-190 p.
azobenzene-containing polymers, ferrocene-based polyesters, liquid-crystalline polymers, thermal properties
IdentifiersURN: urn:nbn:se:kth:diva-118603DOI: 10.1002/pat.3068ISI: 000314049100008ScopusID: 2-s2.0-84872957124OAI: oai:DiVA.org:kth-118603DiVA: diva2:607205
QC 201302222013-02-222013-02-212013-02-22Bibliographically approved