利用二苯基甲烷二異氰酸酯合成聚亞醯胺及其奈米複合材料之研究

Abstract

本論文主要分為兩個部份：第一部份有別於一般以雙胺類 (Diamine)為起始單體合成聚亞醯胺(Polyimide)，主要探討利用價格較為低廉之二苯基甲烷二異氰酸酯(Methylene Diphenyl Diisocyanate, MDI) 單體合成出五大系列，分別為 (1) 聚脲酯-聚亞醯胺 (Polyurea-imide, PUI), (2) 聚脲酯-聚醯胺-聚亞醯胺 (Polyurea-amide-imide, PUAI), (3) 聚脲酯-聚亞醯胺-聚酯 (Polyurea-imide-ester, PUIE) (4) 聚亞醯胺-環氧樹酯 (Polyimide-epoxy, PIE) (5) 聚醯胺-聚亞醯胺-環氧樹酯 (Polyamide-imide-epoxy, PAIE)；利用不同比例的均苯四甲酸二酐 (Pyromellitic Dianhydride, PMDA), 羧基鄰苯二甲酐 (Trimellitic Anhydride, TMA), 4’4-二胺基二苯醚 (4’4-Oxydianline, ODA), 雙酚A (Bisphenol-A, BPA) 及環氧樹酯 ( Diglycidyl Ether of Bisphenol-A, DGEBA)進行一系列的合成並添加奈米黏土 (Nano-Clay)製備奈米複合材料，期待可分析出在不同官能基的改變下，做出價格低廉且同時俱備高耐熱及低介電性質的高分子。並進一步以熱重分析儀 (Thermal Gravimetric Analysis, TGA), 示差掃描量熱儀 (Differential Scanning Calorimetry, DSC), 熱機械分析儀 (Thermomechanical Analysis, TMA) 進行熱性質分析；掃描式電子顯微鏡 (Scanning Electron Microscope, SEM)和穿透式電子顯微鏡 (Transmission Electron Microscopy, TEM) 探討有機-無機混成材料之表面型態；亦探討機械性質及介電性質的影響。由實驗中可知當含有亞醯胺官能基 (Imide Group)含量越多時，其熱性質及機械性質均有較佳的結果；當合成聚亞醯胺-環氧樹脂 (Polyimide-epoxy, PIE)時，其熱裂解溫度可高達500 oC以上，介電常數則介於3.3-3.5之間，在價格較Kapton®低廉時便可得到與之相對應的特性。 第二部分主要為使用不同甲基數目的二胺類與二酸酐類並利用一步法進行合成，進而探討其不同甲基數目對材料性質的影響。主要利用4,4’-diamino-3,3’-dimethyl-diphenyl-methane (DDMDPM)，4,4’-methylene -bis(2-ethyl-6-methylaniline) (MBEMA); 和 4,4’-methylene-bis(2,6-diethylaniline) (MBDEA)這三種胺4,4'-聯苯醚二酐 (4,4’-oxydiphthalic anhydride, ODPA)及4,4'-(六氟異丙烯)二酞酸酐(4,4'-(Hexafluoroisopropylidene)diphthalic anhydride, 6FDA)此兩種二酸酐進行反應，並探討其熱性質及電氣性質。從結果可得知當甲基數目越多時其介電常數也會隨之下降；而當引入氟系列的元素時其介電更會大幅降低。

In this thesis, it is composed of two major parts: The first part is synthesis the kinds of polyimide by Methylene diphenyl diisocyanate (MDI). By adjust the molar ratio of Pyromellitic Dianhydride (PMDA), Trimellitic Anhydride (TMA), 4’4-Oxydianline (ODA), Bisphenol-A (BPA), and Diglycidyl Ether of Bisphenol A (DGEBA) to synthesis polyurea-imide (PUI), polyurea-amide-imide (PUAI), polyurea-imide-ester (PUIE), polyimide-epoxy (PIE), and polyamide-imide-epoxy (PAIE). The purpose of this study is using much cheaper materials to synthesis high thermal properties and low dielectric constant polymers. The thermal properties are measure by Thermal Gravimetric (TGA), Differential Scanning Calorimetry (DSC), and Thermomechanical Analysis (TMA); the morphologies of polymer/nano-clay are observed by Scanning Electronic Microscopy (SEM) and Transmission Electron Microscopy (TEM); and also measured the mechanical and electronic properties. The results of this study are shown that when imide groups are more, it will have good thermal and mechanical properties. The best polymer of this study is polyimide-epoxy (PIE), the degradation temperature is over 500 oC, and the dielectric constant is between 3.3-3.5. Therefore, polyimide-epoxy (PIE) polymer is much cheaper and also has higher performance as Kapton®. The second part is synthesis the new soluble polyimides which were synthesized from different 4,4'-diaminodiphenylmethane monomers with different alkyl substituents (4’4’-diamino-3,3’-dimethyl-diphenyl-methane, DDMDPM; 4,4’-methylene -bis(2-ethyl-6-methylaniline), MBEMA; and 4,4’-methylene-bis(2,6-diethylaniline), MBDEA)) in one-step with the poly(amic acid)s prepared from the polyaddition of 4,4’-oxydiphthalic anhydride (ODPA) and 4,4'-(Hexafluoroisopropylidene)diphthalic anhydride (6FDA). These polyimides exhibited excellent thermal stability, and they also possessed relatively low coefficients of thermal expansion and dielectric constants.