title: Orderly arranged NLO materials based on chromophore-containing dendrons on exfoliated layered templates.
abstract: Three chromophore-containing dendrons were intercalated into montmorillonite layered silicates via an ion-exchange process. Enlarged d spacings ranging from 50 to 126 A were achieved for these novel organoclays. After the organoclays were blended with a polyimide, the steric bulkiness of the dendrons and the interaction between dendron and polyimide resulted in an ordered morphology. The orderly arranged nanocomposites were characterized by a UV-visible spectrophotometer, a variable-temperature infrared spectrometer, and electro-optical modulation. The dendrons in layered silicates were capable of undergoing a critical conformational change into an ordered structure, indicated by the drastic changes of interlayer distances at certain packing densities. Electro-optical coefficients increased sharply from 0 to 6 pm/V while the conformational change occurred. Furthermore, the addition of a polyimide capable of interaction-induced orientation was found to exert an enhancing effect on the degree of the noncentrosymmetric alignment.
authors.affiliation: Department of Chemical Engineering, National Chung Hsing University, Taichung 402, Taiwan.
authors.forename: Yung-Chung
authors.initials: YC
authors.lastname: Chen
authors.forename: Tzong-Yuan
authors.initials: TY
authors.lastname: Juang
authors.forename: Tzong-Ming
authors.initials: TM
authors.lastname: Wu
authors.forename: Shenghong A
authors.initials: SA
authors.lastname: Dai
authors.forename: Wen-Jang
authors.initials: WJ
authors.lastname: Kuo
authors.forename: Ying-Ling
authors.initials: YL
authors.lastname: Liu
authors.forename: Franklin M C
authors.initials: FM
authors.lastname: Chen
authors.forename: Ru-Jong
authors.initials: RJ
authors.lastname: Jeng