以聚二甲基矽氧烷(KF-6001, Polydimethylsiloxane, PDMS, 1800 g/mol)為雙醇基，先和過量之IPDI進行反應，形成末端-NCO官能基之PU預聚合物(PDMS-NCO)，接著再和aminopropyl triethoxysilane (APTES)反應，形成末端-Si(OH)3之PU 寡聚物(PDMS-APTES)；改質後之PDMS-APTES，分別摻混四乙氧基矽烷(TEOS)或奈米級二氧化矽(Nano-silica)，利用溶膠法，形成含PDMS之PU與奈米矽膠之混成物。探討添加不同量的四乙氧基矽烷或奈米級二氧化矽其所形成的性質差異，並以量測混成物之物理性質如膠含量、對水與乙醇吸收損失率、接觸角及硬度等方面都比原本PDMS-APTES皆有所提升，在UV/vis穿透度，隨添加量而有所下降，在熱性質方面使用熱重分析(TGA)測量，發現其熱安定性皆有所提升;在動態機械分析(DMA)測量，可以發現改質後的軟鍊端Tg比之前PDMS-APTES還要低溫而硬鏈端比之前高溫;最後並利用掃描式電子顯微鏡(SEM)觀察材料截面型態，發現TEOS和Nano-silica等皆均勻分佈PDMS-APTES基材，並無相分離現象發生。 A PDMS-containing PU oligomer with triethoxysilane as the terminal groups that is obtained from NCO-terminated PU prepolymer with aminopropane triethyoxysilane (APTES). This PU prepolymer (PDMS-APTES) is prepared by the reaction of polydimethylsiloxane diol (KF-6001) with excess amount of isophorone diisocyanate (IPDI). PU/silica hybridized composites are obtained by the blending of PU prepolymer (PDMS-APTES) with tetraethoxysilane (TEOS) and nano-silica in various dosages, via a sol-gel processes, respectively. The PU/silica hybrids are evaluated by the measurements of physical properties, such as gel content, water absorption, contact angle, hardness. Even though the thermal stability (TGA) increases and the transmittance of UV/visible spectrum is decreases as increasing nano-silica dosage. That is due to the aggregation occurs when the dosage of nano-silica increases, however, SEM micrographs proves that the dispersion of silica is still in nano-scale.
