Application and control of large-scale deformation (mechano-optical deformation) induced by photoirradiation

点击翻译按钮获取中文摘要

The photo-responsible film was prepared during the first year and the photochemical properties of the films were investigated during the second year. The details are described in the following.1.Preparation of block copolymer and azobenzene derivative : Poly (N,N-dimethyl-4-vinylphenethylamine-block-stirene) block copolymer (PPTA-b-PSt) was prepared by anionic living polymerization. p, p'-Bis (chloromethyl) azobenzene (CAB) was prepared from p-nitrobenzyl alcohol.2.Preparation and characterization of the cross-linked photo-responsible films : We could control the degree of quaternization of PPTA from 0% to 100% by using the appropriate reaction time and temperature. Both the ends of CAB were attached to amino groups of PPTA in the block copolymer by quaternization to permit cross-linked films. A UV spectrum of the film showed three absorption peaks due to the trans and cis form of CAB.3.Evaluation of photo-recording properties : When the films were irradiated with ultraviolet light (UV), CAB underwent photoisomerization from the trans to the cis form. The retention and deletion of the cis form were controlled by an alternation of the thermal motion of PPTA in the block copolymer.4.Application and control of mechano-optical behavior : When the films were irradiated with UV light above a glass transition temperature of PPTA,the film was deformed by conformational changes of CAB.The process should be utilized to induce photostimulated mechanical motion (mechano-optical deformation). In order to suppress and/or stimulate the mechano-optical deformation of the film, a systematic photochemical study was carried out in detail. Photo-irradiation time dependence of the films was analyzed by KWW equation to estimate the results.