Please use this identifier to cite or link to this item: http://hdl.handle.net/11455/3466
標題: Aromatic Azetidine-2,4-diones的合成及在高分子之應用
作者: Yi, Wu Mei
吳美儀
關鍵字: 異氰酸鹽;聚醯胺樹脂;聚醯胺彈性體;高分子;聚氨基甲酸酯
出版社: 化學工程學系
摘要: 
This study concerns the thermally induced cycloaddition reactions of ketenes with Methylene-(diphenylene isocyanates), MDI. Through the optimization of reaction condition and ketene candidates, we have found high yield syntheses of mono- and bis-azetidine-2,4-diones.
Aromatic azetidine-2,4-diones have been found to have several good characteristics to be used for as polymer intermediates. Firstly, they are thermally stable even heated to 220 ℃ for short period of time without sign of decomposition. Secondly, they react rapidly and almost quantitatively with aliphatic primary amines into malonamide derivatives at ambient temperature. Lastly, the reactions of azetidine- 2,4-diones with alcohols, secondary amines, and aniline are far less slower than those of aliphatic amines, such that the latter tend to be dominant when mixture of the above were co-existing as the co-reactants.
We also have investigated the polymerization of aliphatic amines with bis-azetindine-2,4-diones and have prepared several high molecular weight malonamides. Polymerization could be conveniently carried out in the melt by mixing to the bis-azetidine-2,4-diones with primary amines in absence of solvent. The thermal analysis of the polymer showed that Tgs are 90~135℃ and Tds are generally greater than 330 ℃. The speed of the ring-opening reaction seems to be slightly slower than those of polyurethane preparation, but thermal stability seems superior. Further research should be able to utilize bis-azetidine-2,4- diones for one-shot syntheses of polyamides and polyamide elastomers.

本研究以Methylene-(diphenylene-isocyanate)【MDI】和Ketenes以熱化學方式合成Aromatic Mono-及Bis-azetidine-2,4-diones。觀察那一種Ketene較適合於反應,並發展出一最佳的反應條件。
所製得之芳香族Azetidine-2,4-diones發現具有如下優良特質:(1)它的熱穩定性高,即使加熱至220℃也無分解之跡象。(2)它是一具有高選擇性的官能基,可與脂肪族的一級胺在室溫即可進行開環反應,且其加成反應快速、產率極高,而且無副產物之生成。(3)脂肪族的一級胺與含羥基之化合物,或是和苯胺及二級胺,若同時同步進行開環時,一級胺具有絕對的優勢。
由於上述Azetidine-2,4-dione的特殊化性,本研究也以合成之不同取代基的Bis-azetidine- 2,4-diones為高分子原料,和脂肪族一級胺混合作用,利用熔融法進行開環作用,而形成非結晶型、高分子量Polymalonamides。所製得的Polymalonamides一般之Tg在90~ 130℃之間,高分子量的Polymalonamides的Td(TGA)皆高於330 ℃,顯示其抗熱性較PU佳。這種以快速熔融法可一步合成的高分子中間體,將有助於新型聚醯胺樹脂(Polyamide)及醯胺類彈性體的後續研發。
URI: http://hdl.handle.net/11455/3466
Appears in Collections:化學工程學系所

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