含有米氏酸結構的可交聯高分子之合成與其熱固化樹脂之性質研究

Preparation of crosslinkable polymers possessing Meldrum's acid groups and the properties of the corresponding thermally-cured resins

周育楷(Chou, Yu Kai)

指導教授 ： 劉英麟

國立清華大學/工學院/化學工程學系/碩士(2015年)

https://doi.org/10.6843/NTHU.2015.00066

摘要

本研究以逐步聚合反應合成主鏈含有米氏酸結構的高分子，並探討其熱硬化後之聚合物之性質。第一部分直接利用米氏酸為單體與二-氯甲基-苯化合物進行縮合反應，合成帶有米氏酸結構的長鏈高分子，利用紅外光譜儀(FTIR)探討其基本鑑定及結構。所合成高分子可以於270 oC下進行交聯反應，形成網狀交聯的分子，但所合成之高分子其於有機溶劑中之溶解度不佳，導致不易加工，雖改用帶有甲基取代基的二-氯甲基-苯化合物作為單體，所得到的高分子之溶解度也沒因此而有所改善，應該是分子結構過於剛硬以及分子間作用力太強致使此類高分子之溶解度不佳。
第二部分則先合成帶有雙呋喃基的米氏酸化合物作為單體，利用紅外光譜儀(FTIR)、核磁共振光譜儀(NMR)、質譜儀(mass spectrometry)、元素分析儀(EA)鑑定其化學結構，接著將其與雙馬來醯亞胺化合物經由Diels-Alder加成反應進行聚合，形成帶有米氏酸官能基的高分子，此高分子亦可進行熱交聯反應，透過米氏酸結構開環聚合形成網狀高分子，交聯樹脂具有良好的熱性質。

關鍵字

乙烯酮 ； 米氏酸 ； 呋喃 ； 二聚合反應 ； 親核加成反應 ； 縮合聚合反應 ； 四圓環

並列摘要

Abstract
This study focuses on the synthesis of polymers possessing Meldrum’s acid (MA) groups at the main chains and the studies on their crosslinking reactions and the properties of the corresponding crosslinked polymers. In the first part, MA is used as a monomer to directly polymerize with 1,4-bis(chloromethyl)benzene or 2,5-bis(chloromethyl)-p-xylene through the dehydrochlorination condensation reaction. The resulting polymers contain MA groups which could perform thermally-induced dimerization, so as to make the polymers thermally crosslinkable. The thermally crosslinking reactions were monitored with a Fourier transform infrared spectroscopy to demonstrate the MA decomposition, formation of active ketene groups, and dimerization of ketene groups take place in the crosslinking process. As a result, crosslinked polymers could be obtained at 270 oC for 1 h. Nevertheless, the solubility of the obtained polymers was poor so as to limit their molecular weights and processing properties. Although 2,5-bis(chloromethyl)-p-xylene was used as a monomer instead, the solubility of the polymer was not therefore improved. It could be referred that intermolecular structure was too rigid and intermolecular forces was so strong to cause such a polymer of poor solubility.
In the second section, a MA monomer possessing two furan groups (MA-FBCB) was synthesized and used as a monomer to polymerize with a bismaleimide compound through Diels-Alder (DA) reaction. The polymer also possessed MA groups at the main chains and was thermally crosslinkable. After being cured at 230 oC for 15 minutes, the corresponding crosslinked polymer was obtained to show good thermal properties.

並列關鍵字

ketene ； Meldrum's acid ； furan ； dimerization ； Nucleophilic addition ； Knoevenagel condensation

參考文獻

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