- 學位論文
微米及次微米胺基化二氧化矽粒子/環氧樹脂 複合材料之製備與性質之比較性研究
Comparative Studies on the Properties of Epoxy Composite Materials Containing Microscaled and Sub-Microscaled Amino-Modified Silica Particles
摘要
本研究主要是針對不同大小之二氧化矽粒子添加入熱固性高分子『環氧樹脂』在複合材料應用方面來做探討，並且利用鋰鹽(LiCl)破壞胺基(amine)間的氫鍵的概念來改善粒徑小的無機材之分散。首先利用甲基三甲氧基矽烷(methyltrimethoxysilane, MTMS)和胺丙基三甲氧基矽烷(3-aminopropyltrimethoxy-silane,APTMS)在鹼催化下進行溶膠-凝膠法(sol-gel)反應，製備表面具有胺基(-NH2)官能機的二氧化矽粒子，並藉由改變水含量和界面活性劑調控二氧化矽粒子之粒徑大小(Amino-modified silica ，AMS)，分別為160nm (AMSC)、1000nm (AMSP)。進而利用in-situ熱開環聚合方式，製備添加表面胺化修飾的二氧化矽粒子之有機環氧樹脂∕無機二氧化矽複合材料。 本研究中，首先將表面胺化修飾的二氧化矽粒子以傅利葉轉換紅外線光譜儀(FT-IR)及固態核磁共振光譜儀(29Si-NMR、13C-NMR)和掃描式電子顯微鏡(SEM)做基本結構鑑定、型態鑑定；而在性質方面，首先用傅立葉單點式全反射光譜分析(FTIR-ATR)和紫外光可見光光譜儀(UV-Vis)做光學性質的鑑定，使用動態機械分析儀(DMA)、熱示差掃瞄卡量計(DSC)和熱重分析儀(TGA)做熱性質與機械性質鑑定，其次利用穿透式電子顯微鏡觀察二氧化矽在環氧樹脂中的分散現象；綜合所有量測結果顯示，添加0.5%表面胺化修飾的AMSP之環氧樹脂複合材料確實能有效提升整體的熱穩定性、機械強度、耐熱性；但添加入的二氧化矽粒子為AMSC時，由於在環氧樹脂中產生凝集的現象，因此並未如預期的性質較優越於AMSP/ Epoxy。為了改善無機粒子之分散，在AMSC/Epoxy製備過程中先加入少量鋰鹽(LiCl)， 最後由數據結果分析，AMSC/Epoxy複合材料所量測到的性質則較AMSP/Epoxy複合材料的性質來的優異。
並列摘要
Amino-modified silica (AMS) particles with two different diameters (~ 160 nm and ~ 1000 nm) were successfully prepared by conventional base-catalyzed sol-gel process. First of all, the AMS particles prepared by sol-gel process were carried out at suitable feeding ratio of MTMS/APTMS. Size control of AMS particles can be fine-tuned by incorporation of varying with different type of surfactants. The as-prepared AMS particles are characterized by Fourier-Transformation infrared (FTIR) spectroscopy, scanning electron microscope (SEM) and 29Si NMR、13C NMR . Subsequently, the AMS particles were blending into epoxy thermosets by performing thermal epoxide ring-opening polymerization reactions. It should be noted that the epoxy-silica composites containing small AMS particles of ~ 160 nm was found to reveal poor physical properties in DMA and transparency in uv-visible as compared to that of containing large AMS particles of ~ 1000 nm. It indicated that the small AMS particles revealed severe aggregation phenomena in epoxy thermosets matrix, which can be further evidenced by the observation of transmission electron microscopy (TEM). According to the experimental result, it could improve the dispersing of small AMS particles that we added the LiCl in the process of sub-microcomposites. After that, the mechanical properties of sub-microcomposites were better than the microcomposites.