- 楊洪 教授
- 東南大學
- 網址: yangh.polymer.cn 訪問量:827637
關鍵字:MJLCP
論文來源:期刊
具體來源:Polymer Chemistry, 2015, 6, 6709-6719.
發表時間:2015年
Previously reported polymer backbone structures of mesogen-jacketed liquid crystalline polymers (MJLCPs) are still limited to polyacrylate, polystyrene, polyacetylene, polysiloxane, polythiophene and polynorbornene. In this manuscript, we describe a new system of MJLCPs with poly(vinyl benzoate)- backbone (PVBnB), which were synthesized by solution polymerization and bulk photo-polymerization methods. Due to the low reactivity of the vinylbenzoate group, we cannot achieve a high degree of 20 polymerization. Ironically, benefiting from this low reactivity, we successfully prepared several loosely cross-linked MJLCP (xPVBnB) films with homogeneous- or homeotropic-alignment, for the first time by
using UV-illumination on a unidirectional oriented mixture of vinylbenzoate monomers, crosslinkers and
photo-initiators to perform polymerization and cross-linking at the same time, which are however extre-
mely difficult for the much more reactive acrylate-type or styrene-type MJLCPs’ precursor monomers 25
due to the spontaneous thermal-polymerization reactions occurring at high temperatures. Experimental
results show that PVBnB can form nematic or smectic phases depending on the alkyl chain length,
xPVBnB films present very small elastomeric transformations (i.e. shrinkage/wrinkle) during the LC-to-
isotropic phase transition.