本研究利用溶膠-凝膠法在室溫下合成粒徑約90 nm的中空奈米二氧化矽粒子，並藉由偶合劑及氟化矽烷改質奈米粒子表面，以分別提供光聚合所需的C=C雙鍵及增加粒子表面的疏水性。利用穿透式電子顯微鏡及動態光散射來測量中空二氧化矽奈米粒子的型態、尺寸及zeta電位。將中空二氧化矽奈米粒子混合壓克力單體，旋轉塗佈於聚甲基丙烯酸甲酯基板，並以紫外光交聯將塗膜硬化。製作的複合塗膜具有高接觸角及低折射率的特性，且保持良好的可見光穿透度及鉛筆硬度。中空二氧化矽奈米粒子及氟化矽烷的增加可使塗膜接觸角上升，折射率及可見光穿透度下降。以中空二氧化矽含量40 wt%所製作的塗膜為最佳，能兼顧接觸角及可見光穿透度，其接觸角達117 o，折射率1.35且硬度維持4H。 和純壓克力塗膜相較，製作的複合塗膜表現較高的接觸角和較低的折射率，但仍保持良好的穿透度及硬度，隨著塗膜中二氧化矽含量和粒子表面氟化矽烷含量的增加，塗膜的接觸角隨之上升而折射率雖之下降，但可見光穿透率亦隨之下降。 In this study, ~90 nm spherical hollow silica nanoparticles were synthesized by the sol-gel method at room temperature. The synthesized hollow nanoparticles were surface-modified using the coupling agent and a fluorosilane in order to provide C=C bonds and hydrophobicity, respectively. The morphology and size/zeta potential of the formed nanoparticles were observed and measured by transmission electron microscopy and dynamic light scattering, respectively. Transparent composite coatings composed of the nanoparticles and acrylic monomer were prepared on the poly(methyl methacrylate) substrate via spin coating followed by UV-curing. Compared with the primal acrylic coating, the composite coatings showed higher water contact angles and lower refractive indices, while remained good visible transparency and pencil hardness. The contact angles of the coatings were increased but the refractive indices were decreased with increasing the silica content in the coating and fluorosilane content on the particle surface. However, the transmittances were decreased with these two. In the extreme case, a composite coating containing 40 wt% hollow silica nanoparticles with pencil hardness of 4H, a contact angle of 117o, and a refractive index of 1.35 was obtained.
