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。

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.

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