光硬化蒙脫土-環氧樹脂奈米複合物之製備研究

Abstract

本論文研究利用四級胺鹽（Quaternary Alkylammonium Salt），Hexadecyl Trimethylammonium Bromide（HDTMA）與[2-(Methacyloyloxy)ethyl] trimethylammonium Methyl Sulfate（MAOTMA），將PK802蒙脫土（Montmorillonites，MMT）改質成有機化蒙脫土，並將其摻混於環氧樹脂（Epoxy）中以製備出蒙脫土-環氧樹脂的奈米複合膠材，膠材試樣以行星式研磨（Planetary Ball Mill）進行有機化蒙脫土於樹脂基材中之分散，之後探討分散劑種類、研磨鋯珠粒徑對奈米複合物之微觀結構、熱性質、黏著性質與透光性之影響。 XRD分析顯示蒙脫土層間距由改質前的1.18 nm分別增加至1.90（經HDTMA改質）和1.39 nm（經MAOTMA改質）；由ICP-MASS分析可知蒙脫土層間可交換的鈉離子幾乎完全被取代出來；XRD分析亦顯示行星式分散研磨較傳統的超音波/磁石攪拌有更好的分散效果。 改質劑MAOTMA能參與環氧樹脂的聚合反應，實驗結果得知以其進行改質的蒙脫土在奈米複合物中可達到接近完全脫層，其尺寸安定性佳，熱穩定性提升；而有機改質劑HDTMA不參與環氧樹脂的聚合反應，其製備的奈米複合物為部份插層、部分脫層，尺寸安定性雖提升但較MAOTMA之效果差。奈米複合物之形成會略為影響黏著力和透光度，但無重大之劣化。 經由鋯珠粒徑2 mm和0.5 mm研磨都能達到分散均勻的目的，然而小粒徑研磨可得到較佳之分散及尺寸安定性效果，但熱穩定性則以大粒徑研磨較佳；整體而言，以小粒徑的研磨能製備性質較佳的奈米複合物。

Two different types of quaternary alkylammonium salts, hexadecyl trimethylammonium cation (HDTMA) and [2-(methacyloyloxy)ethyl] trimethylammonium cation (MAOTMA), were adopted to modify montmorillonite (MMT) in order to prepare the epoxy/MMT nanaocomposites. Planetary ball mill was also adopted to disperse the organically modified MMT in polymer matrix. The influence of quaternary alkylammonium salt type, zirconium (Zr) beads size on the morphology, thermal stability, adhesion and transmittance of nanocomposites were investigated accordingly. X-ray diffraction (XRD) indicated the interplanar spacing of MMT increases from 1.18 nm respectively to 1.90 nm (by HDTMA) and 1.39 nm (by MAOTMA). ICP-MASS analysis revealed the Na+ ions on MMT lamella are almost all exchanged by the modification agents. XRD analysis also indicated that the planetary ball mill provides a superior dispersion effect of modified MMTs in epoxy in comparison with conventional ultrasonic vibration/magnetic stirring method. Since the MAOTMA may join the polymerization of epoxy, it implied a nearly exfoliated MMT structure in epoxy and consequently improved the dimension stability and thermal stability of nanocomposite samples. The HDTMA-modified MMT did not react with epoxy resin; it implied a mixture of partly intercalated, partly exfoliated MMTs in epoxy and a slightly inferior improvement on dimension stability. Formation of nanaocomposites affected the adhesion and transmittance of epoxy, nevertheless, no severe damage occurred. Planetary ball mill using Zr beads sizes of 0.5 or 2 mm provided satisfied dispersion effect, however better improvements were obtained in dispersed structure and dimension stability via the 0.5-mm bead milling. Though a better thermal stability improvement was obtained by the 2-mm bead milling, the 0.5-mm bead milling is the choice for a better overall improvement on physical properties and microstructure of nanocomposites.