本研究以米氏酸單體及衍生物合成具有反應性官能基的高分子為目的。第一部分先合成帶有雙端米氏酸官能基之單體(MPM)，因二異氰酸酯官能基能催化米氏酸的熱裂解開環溫度，可於較低溫下生成烯酮官能基，並與脂肪族及芳香族的二異氰酸酯進行加成反應，合成具有反應選擇性的azetidine-2,4-dione官能基，但所合成之高分子的溶解度相當差，嘗試改變反應物的當量比或加入醇類皆無法改善其溶解性，因此無法進行後續的加工應用。
第二部分則利用米氏酸結構上高反應性的C-H鍵與二異氰酸酯進行反應，成功合成帶有米氏酸結構的聚醯胺高分子，其中與脂肪族的二異氰酸酯合成之高分子溶解度較差，而與芳香族的二異氰酸酯合成之高分子溶解度較好。因此使用兩倍當量的芳香族二異氰酸酯合成尾端帶有異氰酸官能基的寡聚物，並加入乙二醇、聚乙二醇或己二醇進行合成反應，製備帶有可自交聯特性的米氏酸官能基、醯胺官能基及氨基甲酸乙酯官能基之高分子，且具有良好的溶解性，並利用此三種高分子進行熱交聯反應製備薄膜及熱固性樹酯。

The purpose of this study is to synthesize reactive polymers based on Meldrum’s acid (MA) derivatives. In the first section, a bifunctional Meldrum’s acid compound (MPM) is synthesized and characterized by Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance (NMR) spectroscopy. MPM has been used as a monomer to react with diisocyanate compounds for preapartion polymers possessing azetidine-2,4-dione groups. It is found that the isocyanate group might catalyze the thermolysis reaction of MA groups. Nevertheless, due to the poor organosolubility of the obvtained polymers, further studies are blocked.
In the second section, polyamide possessing MA groups have prepared through the reaction between the highly reactive C-H bond of MA and isocyanate group. Polyamide from aromatic diisocyanate precursor shows better solubility than that from aliphatic diisocyanate. Consequently, excess aromatic diisocyanate has been employed to result in telechelic MA-containing oligomers with isocyanate endgroups, which have been further reacted with ethylene glycol, polyethylene glycol, and 1,6-hexanediol to result in the corresponding MA-containing polyamide-urethane. The polymers show good organosolubility for further processing. Based on the thermally-induced MA reactions, the polymers are self-crosslinkable. The corresponding thermosetting resins have been prepared and their properties are discussed.

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