立體規則度對聚丙烯腈共聚物環化機制之影響

Effect of tacticity on the cyclization mechanism of polyacrylonitrile copolymers

潘世允(Shih-Yun Pan)

指導教授 ： 芮祥鵬

國立臺北科技大學/工程學院/有機高分子研究所/碩士(2014年)

摘要

本篇研究選用丙烯酸甲酯(MA)與二甲酯衣康酸(DMI)為第二單體，於總體聚合法中，添加氯化鎂來改善聚丙烯腈共聚物之立體規則度(Tacticity)。合成出之聚丙烯腈共聚物利用核磁共振儀(1H-NMR、13C-NMR)鑑定其分子結構；使用凝膠滲透層析儀(GPC)對合成之共聚物進行分子量特性分析；搭配X光單晶繞射儀(XRD)做結晶測試；用傅立葉轉換紅外線光譜（FT-IR）來分析特定官能基；透過熱示差掃描分析儀(DSC)研究其熱性質及恆溫狀態下的環化反應。
實驗結果表示，由13C-NMR可看出，在總體聚合裡我們使用氯化鎂當作催化劑來控制聚丙烯腈共聚物 [P(AN-co-DMI)]和[P(AN-co-MA)]的同排結構，而其同排結構比例可以從大約30％提升至50％。在恆溫DSC的實驗裡可以看出，當我們的同排結構比例提高，能有助於縮短環化反應的時間，改善聚丙烯腈共聚物穩定化過程的環化反應。

關鍵字

聚丙烯腈無水氯化鎂 ； 立體規則度 ； 熱分析

並列摘要

In this study, we synthesized polyacrylonitrile copolymers with controlled tacticity on the basis of the strategy of the bulk polymerization of acrylonitrile (AN) in the presence of magnesium chloride, and we selected methacrylate(MA) and dimethyl itaconate (DMI) as comonomer. All polyacrylonitrile copolymers were using 1H-NMR and 13C-NMR to identify its molecular structure, and the polymers’ molecular weights were characterized by gel permeation chromatography. Moreover, X-ray diffraction was utilized to determine the crystallinity; Fourier Transform Infrared Spectrometer was utilized to analyze its functional groups；Differential Scanning Calorimetry (DSC) was defined to evaluate the extent of isothermal cyclization of stabilization process.
The 13C-NMR results show that the magnesium chloride was successfully used as catalyst for bulk polymerization of AN to control tacticity of PAN copolymers, [P(AN-co-DMI)] and [P(AN-co-MA)], whose contents of isotacticity increase from 30% to 50%. In the isothermal DSC studies, we found that the cyclization reaction time of the PAN copolymers decrease with increase isotacticity structure. Those studies indicated that bulk polymerization can effectively enhance isotactic structure result in favorite cyclization reaction during stabilization process.

並列關鍵字

polyacrylonitrile ； Anhydrous magnesium chloride ； tacticity ； thermal analyzer

參考文獻

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