米氏酸衍生物與氧代氮代苯并環己烷化合物之共硬化反應特性及其共聚合物性質之研究

Characteristics of curing reaction and properties of crosslinked resins of the reactive blends of Meldrum’s acid derivatives and benzoxazine compounds

陳宜(CHEN,YI)

指導教授 ： 劉英麟

國立清華大學/工學院/化學工程學系/碩士(2016年)

摘要

本研究以米氏酸進行聚合反應，推測其聚合反應機制，並探討其熱硬化後之聚合物之性質。第一部分，將米氏酸衍生物摻混等當量之氧代氮代苯并環己烷(benzoxazine)單體，因其帶有三級胺的結構為Lewis bases可將米氏酸活化，使米氏酸開環反應溫度降低，藉由微差掃描卡計儀(DSC), 熱重分析儀(TGA), 紅外光譜儀(FT-IR)與核磁共振光譜儀(NMR)儀器證實其催化效果，並推測其催化反應機制。更進一步，藉由此反應機制，以不同當量米氏酸衍生物(MA-F)改質聚氧代氮代苯并環己烷單體(BPA-FBZ)，然而其產生酯基的鍵結較弱，因此隨著添加的MA-F比例越高其熱穩定性則有較差的表現。
第二部分，將米氏酸衍生物(MA-FBCB)與雙馬來醯亞胺化合物進行Diels-Alder加成反應而聚合得到高分子(MA-FBCB-BMI)，藉由微差掃描卡計儀(DSC), 熱重分析儀(TGA)與紅外光譜儀(FT-IR)鑑定其結構與純度，而此高分子相對於反應物米氏酸單體有更好的溶解度，增加了其後續加工的能力，而經由熱處理後所得到的交聯高分子，具有好的熱穩定性與低介電常數。

關鍵字

乙烯酮 ； 米氏酸 ； 二聚合反應 ； 親核加成反應 ； 四圓環 ； 氧代氮代苯并環己烷 ； 狄爾斯阿爾德反應

並列摘要

This study focuses on Meldrum’s acid (MA) polymerization mechanism as well as the properties of the correspond crosslinked polymers. In the first part, MA derivatives are blended with benzoxazine compound (F-BZ) with tertiary amine structure, which is a Lewis base, to undergo thermolysis at a much lower temperature. By means of DSC, TGA, FT-IR and NMR characterization, we confirmed its catalytic effect and mechanism. Furthermore, by this reaction mechanism, different equivalent MA derivative (MA-F) are applied to modify polybenzoxazine. Results indicate polymers modified with MA-F have poor thermal stability due to the week bonding of ester group.

In the second part, MA monomer with two furan group (MA-FBCB) was synthesized and used to polymerize with a bismaleimide compound through Diels-Alder reaction (DA reaction). The molecular structure was further verified by DSC, TGA, FT-IR. This polymer has better solubility and hence better potential than MA monomer (MA-FBCB). After crosslinking, a material with better thermal behavior and low dielectric constants was obtained.

並列關鍵字

ketene ； Meldrum's acid ； dimerization ； Nucleophilic addition ； benzoxazine ； diels- alder reaction

參考文獻

1. Leibfarth, F.A., et al., A facile route to ketene-functionalized polymers for general materials applications. Nat Chem, 2010. 2(3): p. 207-212.

2. González, L., et al., Reduction of the shrinkage of thermosets by the cationic curing of mixtures of diglycidyl ether of bisphenol A and 6,6-dimethyl-(4,8-dioxaspiro[2.5]octane-5,7-dione). Journal of Polymer Science Part A: Polymer Chemistry, 2006. 44(23): p. 6869-6879.

3. Fillion, E., et al., Meldrum's acids as acylating agents in the catalytic intramolecular friedel−crafts reaction. The Journal of Organic Chemistry, 2005. 70(4): p. 1316-1327.

4. Wolffs, M., M.J. Kade, and C.J. Hawker, An energy efficient and facile synthesis of high molecular weight polyesters using ketenes. Chemical Communications, 2011. 47(38): p. 10572-10574.

5. Wu, C.-Y., et al., Liberation of small molecules in polyimide membrane formation: An effect on gas separation properties. Journal of Membrane Science, 2016. 499: p. 20-27.