本研究中,藉由醯氯反應合成出含有偶合基團的雙胺單體3,5-di aminobenzamide n-propyltriethoxylsilane(PTSDA),然後以此一新單體與m-phenylenediamine (PDA)及hexafluoroisopropylidene diphthalic dianhydride (6FDA)調配不同比例來進行溶凝膠反應以製備聚醯亞胺/二氧化矽混成材料。 我們藉由AFM來觀測材料的表面型態、SiO2粒子大小及分佈情形,由UV-Vis來觀測有無光散射現象產生,並從AFM及UV-Vis結果可以得知,未添加含有偶合基團雙胺時,水是影響溶凝膠反應最大的因素,水添加量過多易造成SiO2粒子的聚集,使得粒子有變大的趨勢。當添入含有偶合基團PTSDA後,會有助於有機-無機兩者間相容性提升,並且有效降低SiO2粒子,且光訊號的損失可藉由SiO2粒子添加量來調控。此外,由TGA及DSC結果顯示,摻合SiO2粒子的聚醯亞胺,其熱裂解溫度均可維持在500 ℃以上,玻璃轉化溫度亦可保持在290 ℃以上,並且DMA的量測結果亦顯示,添加SiO2含量越高,材料的硬度亦會因此而提升,其楊氏模數值均可維持在1GPa以上。由研究結果顯示,所製備的聚醯亞胺/二氧化矽混成材料具有高度均勻性、透光性,以及可調整的光學性質,因此深具光學材料的應用潛力。 除此,本研究也將以實驗規劃法,尋找出製備混成材料的最適化反應條件,以期能達到製備擁有最佳熱穩定性、機械強度與介電性的聚醯亞胺-二氧化矽混成材料。在此實驗設計方法中,我們利用實驗數據建立了類神經網路的模式,最後可求得最佳配方,即向整體最佳解收斂。利用此均勻設計模式,不需要繁瑣的數學運算就可以直接使用,大大增加實驗人員的方便性,只需利用少量的實驗數據建立可靠的模式來求取最適化條件。
In this study, a coupling agent of 3,5-diaminobenzamide n-propyl triethoxylsilane (PTSDA) was synthesized by the acid chloride reaction and used as a diamine monomer to react with m-phenylenediamine (PDA) and hexafluoroisopropylidene diphthalic dianhydride (6FDA) to prepare polyimide-silica hybrid materials. The morphology, microstructure and the particle sizes and their distribution of silica in hybrid materials was examined by AFM and the light transmission studied by UV-VIS. Based on this study, water content is one of major factors to affect the size of SiO2. However, addition of PTSDA would decrease the size of SiO2 and reduce light scattering and optical loss. In addition, all of hybrid materials prepared in this study show good thermal stability (>500℃) and mechanical strength (Young’s modulus>1GPa). It is shown that these hybrid materials could play important roles in optical applications. Finally, we try to use experimental design to optimize material properties. Under appropriate design, we can use artificial neural network and genetic algorithm to obtain optimized preparations.