- 期刊
乙烯氧基甲醚為尾端基熱向型液晶共聚合物合成、熱性質及微結構之研究
Synthesis Mesomorphic Behavior and Micro-Structure of Terminally Carboxyl Oligo (Ethylene Oxide) Monomethyl Ethers-Substituted Side Chain Liquid Crystalline Copolysiloxane Polymers
摘要
一系列不同鏈長之乙烯氧基甲醚及(±)2-甲基-乙烯氧基甲醚為末端基(terminal group)，二苯基苯酯(carboxyl biphenyl benzoate)及對-(對-(苯甲酸)苯酯)(p'(p'-phenyl)benzoate es-ter)為液晶基(mesogenic group)之烯烷液晶單體，配對接枝到聚矽烷鏈聚合物側鏈上，形成液晶共聚合物。以氫-核磁共振光譜(^1H-NMR)分析共聚合物之組成，並利用偏光顯微鏡、微差掃描卡計(DSC)、及X-ray繞射儀分別測定液晶共聚合物之晶態種類、玻璃轉移溫度(glass transition temperature, T_g)與等方向性溫度(isotropization temperature, T_i)、及層間距(layer spacings, d_l)，探討組成與單體之晶態對液晶共聚合物之熱性質、晶態及液晶分子結構之影響；研究同時發現，適當的選擇兩種層列相(Smeetic phases)液晶單體與組成進行共聚合，可獲得層列相帶狀(smetic phase schlieren texture)液晶共聚合物。
並列摘要
The polysiloxane copolymers were obtained by grafting the correspounding pair monomers which contained olige (ethylene glycol) monomethyl ethers or (±) 2-methyl-ethylene glycol monomethyl ether as terminal group onto the poly (methyl hydrosiloxane). The mesomorphic properties of polysiloxane copolymer have been studied by the method of polarized optical microscopy, DSC, and X-ray diffraction analysis. The effects of change in composition on the LC texture, isotropic temperature, enthalpy changes of isotropic temperature, and layer spacing (d_l) of these copolymers were also discussed. By selecting suitable two smectic phase monomers for copolymerization, smectic phase schlieren texture copolymers have been prepared.