Thermal and Photo Alignment Behavior of Polyethylene Imine Having Methoxy Substituent Azobenzene Side Chain Group

Mohammad Kamruzzaman, Sun-nam Kim, Yutaka Kuwahara, Tomonari Ogata, Seiji Kurihara

Department of Applied Chemistry and Biochemistry, Graduate School of Science and Technology, Kumamoto University, Kurokami, Kumamoto, Japan.
Department of Applied Chemistry and Biochemistry, Graduate School of Science and Technology, Kumamoto University, Kurokami, Kumamoto, Japan&PHOENICS, 3-11-38 Higashimachi, Higashi-ku, Kumamoto, Japan&JST-CREST, 5 Sanbancho, Chiyoda-ku, Tokyo, Japan.
Innovate Collaboration Organization, Kumamoto University, Kurokami, Kumamoto, Japan.

DOI: 10.4236/ojpchem.2013.34016                

Abstract

Novel type of polyethylene imine having methoxy (–OCH₃) substituent azobenzene side chain group through eight methylene spacer group (PEI8M) was successfully synthesized and characterized by the polymer by ¹H NMR, differential scanning calorimetry, polarized optical microscopic and X-ray diffraction analysis. Synthesized polymer possessed liquid crystalline (LC) properties. Spin coated PEI8M film showed out-of-plane molecular orientation on annealing and non-polarized visible light irradiation. PEI8M in solid film exhibited photoresponsive properties upon irradiation of UV and visible light. PEI8M film also exhibited reversible molecular orientation from random state to out-of-plane and from out-of-plane to random state on annealing, non-polarized UV and visible light irradiation.

Keywords

Azobenzene Polymer; Thermal Alignment Behavior; Liquid Crystalline Properties; Out-of-Plane Ordering

Conflicts of Interest

The authors declare no conflicts of interest.

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