Influence of side-chain structure and irradiation condition on photoalignment of ladder-like polysiloxane films

doi:10.1002/adfm.200400158

CORC > 化学研究所 > 中国科学院化学研究所

	Influence of side-chain structure and irradiation condition on photoalignment of ladder-like polysiloxane films
	Gu, HW ; Xie, P ; Fu, PT ; Zhang, TY ; Zhang, RB
刊名	ADVANCED FUNCTIONAL MATERIALS
	2005
卷号	15 期号:1 页码:125-130
ISSN号	1616-301X
DOI	10.1002/adfm.200400158
英文摘要	In this paper we consider the photo-induced aligning capability of various ladder-like polysiloxane-based photoalignment films-which could be used in liquid-crystal displays-bearing different photoreactive side chains, i.e., laterally grafted cinnamate/azobenzene-based dual photoreactive side chains with a short or longer spacer, and terminally fixed coumarin-containing side chains. Results from polarized optical microscopy (POM), Fourier-transform infrared (FTIR) spectroscopy, surface-enhanced Raman scattering (SERS), atomic force microscopy (AFM), etc., are integrated to elucidate the influence of side-chain structure and the irradiation conditions on the photoalignment of ladder-like polysiloxane films. It is demonstrated that the film containing the dual photoreactive group with a longer spacer exhibits better alignment properties. Reasonably, the concerted photoreactions of the dual photoreactive group and the longer spacer are beneficial to the cooperative motion of chromophores at the "domain level", resulting in improved alignment facility and stability. The complicated effects of irradiation conditions and moderate annealing are also discussed. High-quality alignment of the polysilsesquioxane (LPS)-based photoalignment film LPS-CA11. with a longer spacer between the LPS main chain and cinnamoyl/azobenzene side chains can be achieved only within an optimal range of exposure (5-8 J cm(-2)), while the pretilt angles can be adjusted in the range 0.5degrees-7degrees by varying the incident light intensity. Additionally, moderate annealing before and after illumination can markedly improve the alignment uniformity by self-healing of defects.
语种	英语
出版者	WILEY-V C H VERLAG GMBH
WOS记录号	WOS:000226705500017
内容类型	期刊论文
源URL	[http://ir.iccas.ac.cn/handle/121111/57107]
专题	中国科学院化学研究所
通讯作者	Xie, P
作者单位	1.Chinese Acad Sci, Inst Chem, Joint Lab Polymer Sci & Mat, State Key Lab Polymer Phys & Chem, Beijing 100080, Peoples R China 2.Dow Corning Corp, New Ventures R&D, Midland, MI 48686 USA
推荐引用方式 GB/T 7714	Gu, HW,Xie, P,Fu, PT,et al. Influence of side-chain structure and irradiation condition on photoalignment of ladder-like polysiloxane films[J]. ADVANCED FUNCTIONAL MATERIALS,2005,15(1):125-130.
APA	Gu, HW,Xie, P,Fu, PT,Zhang, TY,&Zhang, RB.(2005).Influence of side-chain structure and irradiation condition on photoalignment of ladder-like polysiloxane films.ADVANCED FUNCTIONAL MATERIALS,15(1),125-130.
MLA	Gu, HW,et al."Influence of side-chain structure and irradiation condition on photoalignment of ladder-like polysiloxane films".ADVANCED FUNCTIONAL MATERIALS 15.1(2005):125-130.