以高分子反應合成新穎聚醯胺高分子及其性質研究

Synthesis and properties of novel polyamides through polymer reactions.

李蕙珍(Hui-Chen Lee)

指導教授 ： 劉英麟

中原大學/工學院/化學工程研究所/碩士(2006年)

https://doi.org/10.6840/cycu200600413

摘要

本研究是以含馬來醯胺二酸單體為基礎，利用直接聚合法與六氟二胺單體和具有醚基的二酸單體共聚，成功地聚合出一系列高分子量的聚醯胺，因為大分子鏈導入了氟原子與馬來醯胺取代基，此系列高分子溶解度良好，易溶於常見的極性溶劑中如N, N-dimethylacetamide (DMAc)、dimethylsulfoxide( DMSO)、N-methyl-2-pyrrolidone (NMP)、tetrahydrofuran (THF)。雖然接上了馬來醯胺會增加剛性，結構變得易脆，但由於馬來醯胺有不飽和雙鍵具有反應性，我們使用含大量柔韌醚基的Polytetrahydrofuran bis(3-aminopropyl) terminated (P-THF)進行加成反應，得到交聯結構的共聚合膜材，經由Instron的測定，增韌後的拉伸率接近60%，顯示聚醯胺增韌改質有所成效。接著利用高溫燒解法，於250℃環境下將P-THF燒解，並以SEM、TEM證明，P-THF受熱裂解形成封閉奈米孔洞，同時由於空氣會充滿這些孔洞之中，聚合物膜材介電常數可減少原本9~23%。
進一步我們將多面體聚矽氧烷寡聚物(polyhedral olgomeric silsesquioxane, POSS)導入聚醯胺高分子中，形成有機-無機複合材料，透過TGA監測熱裂解行為，在空氣環境下POSS含量愈多的膜材，於800℃殘留量也愈多，證明POSS會在表面形成SiO2保護層，提升了高溫區的熱穩定性。另外藉由AFM、SEM、TEM 觀測材料形態，發現POSS比例較少時，與聚醯胺具有不錯的相容性，隨著POSS的比例增加，愈容易出現自身聚集的情形。介電常數方面，由於POSS形成立體障礙影響分子鏈排列，能有效地降低介電常數。

關鍵字

聚醯胺高分子

並列摘要

In this study, a series of novel polyamides having pendant maleimide groups were synthesized by direct polycondensation of 5-male- imido-isophthalic acid with 4,4'-(Hexafluoroisopropylidene) dianiline and 4,4'-Dicarboxydiphenyl ether. All the aromatic polyamides were readily soluble in various polar aprotic solvents such as N, N-dimethylacetamide (DMAc), dimethylsulfoxide (DMSO), N-methyl-2-pyrrolidone (NMP) and tetrahydrofuran (THF). One of the major drawbacks of this maleimide–containing polyamide is their brittleness. To overcome this disadvantage, Polyamides modified with Polytetrahydrofuran bis- (3-aminopropyl) terminated (P-THF) cross-linked structure were obtained through Michael addition reaction. The modified polyamides exhibited 60% with elongation at break. Moreover, these films were thermally treated at 250℃ to decompose P-THF domains and generated pores in polyamide film. The presence of pores were confirmed by SEM and TEM. With the incorporation of air nanopores, the dielectric constants were found to decrease 9~23% comparing with original polyamide film.
Organic-inorganic hybrid materials were also obtained from covalently incorporation combining nanoporous POSS molecules to polyamide. The thermal stability was measured with TGA in air. At 800℃, the film which contained the most POSS content showed the highest char yields . Some POSS might have degraded and evolved out from the matrix under heat. The morphologies of PA-POSS nanocomposites were observed by AFM, SEM and TEM. POSS molecules tethered to polyamide form self-assembled architecture as the mole ratio of POSS is increased. The dielectric constants of PA-POSS were lower due to the increased free volume and the chain interaction.

並列關鍵字

polyamide

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