臺灣博碩士論文加值系統

本研究係以自製三甲基三苯基環三矽氧(1,3,5-trimethyl-l,3,5-triphenylcyclotrisiloxane,D3Ph)，與六苯基環三矽氧(hexaphenylcyclotrisiloxane，P3)為單體 ，正丁基鋰(n-BuLi)為引發劑，二苯基甲基氯矽烷為終止劑，利用陰離子開環聚合法，於不同的溶劑系統中製備了三個系列各含不同二苯基矽氧含量的甲基苯基矽氧/二苯基矽氧(PMPS/PDPS)共聚物。物經由GPC和1H-NMR來鑑定其分子量、分子量分佈及二苯基矽氧的莫耳含量。
我們使用Fineman-Ross法求得三組於不同的溶劑系統反應下之D3Ph、P3單體反應性比，同時比較溶劑的改變對單體反應性比及其對共聚物結構類型的影響，並由產物1H-NMR光譜圖及玻璃轉移溫度(Tg)來證實我們的推測。
最後，藉由微差掃瞄熱分析儀(DSC)、偏光顯微鏡(POM)以及熱重分析儀(TGA)的量測，來探討這三個系列PMPS/PDPS共聚合物的熱性質，包括玻璃轉移溫度(Tg)、介相轉移溫度(Tm)、各向同向性轉移的溫度(Ti，isotropic temperature)及裂解溫度(T10)，與PMPS/PDPS共聚物中PDPS含量及分子量的關係。

Series of Polymethylphenylsiloxane (PMPS)/Polydiphenylsiloxane (PDPS) statistical random copolymers with different PDPS content were synthesized through a living anionic copolymerization from hexaphenylcyclotrisiloxane (P3) and 1,3,5-trimethyl-1,3,5-triphenylcyclotrisiloxaiie (D3Ph) in various solvent system, using n-butyllithium as initiator, and diphenylmediylchlorosilane as terminator. These copolymers were characterized by GPC and 1H-NMR.
The monomer reactivity ratios of the D3Ph/P3 copolyinerization in various solvent system were estimated from Fineman-Ross equation. The monomer sequence of the copolymers was confirmed by the 1H-NMR and the glass transition temperature (Tg) of the synthesized copolymers.
The Tg and mesophase transition temperature (Tm) of these copolymers were determined by Differential Scanning Calorimeter (DSC). The isotropic temperature (Ti) of the copolyiners were measured by the Polarized Optical Microscopy (POM). Basing upon DSC and POM results, the phase diagrams of these copolymers were established. The thermal stability (T10) of these copolymers were measured by Thermogravimetry Analysis (TGA).