| 摘要: | 本論文探討利用原子轉移自由基聚合(ATRP)製備高分子刷狀結構之SiO2次微米球，並且探討不同尺寸大小之均一粒徑SiO2次微米球的製備，以及其光子晶體之排列。 首先利用Stöber所提方法，以四乙氧基矽烷(TEOS)作為單體，可成功合成出158 nm ~ 700 nm之均一粒徑的SiO2次微米球，其Cv值皆小於4%，並將此次微米球經由自組裝排列形成光子晶體，其光子能隙(PBG)可涵蓋整個可見光波段及近紅外光範圍，並呈現出不同的結構性色彩。 由於ATRP是利用粒子表面的鹵素基去進行高分子刷狀結構的聚合反應，因此選用286 nm之SiO2次微米球以3-氯丙基三乙氧基矽烷(CPTS)進行表面改質，以形成表面帶有氯基之SiO2次微米球(即SiO2-Cl)，經由化學分析能譜儀(ESCA)進行表面元素的分析，可觀察出約在198ev位置有氯元素鍵結能(binding energy)波峰的出現，顯示氯基確實存在次微米球的表面。 最後將不同氯基濃度之SiO2-Cl粒子利用ATRP聚合反應製備刷狀結構之SiO2次微米球(SiO2-g-PMMA)，反應系統中以氯化亞銅(CuCl)當金屬觸媒，以N,N,N',N",N"-pentamethyldiethylenetriamine (PMDETA)當作螯合劑，合成出的高分子PMMA重量比率為5.6 % ~ 10.5 %，並經由掃描式電子顯微鏡(SEM)以及穿透式電子顯微鏡(TEM)可證明SiO2-g-PMMA粒子上的PMMA部分約6 nm，由以上結果顯示，本實驗已經可以成功製備出均一粒徑具刷狀結構之SiO2-g-PMMA粒子。 The preparation of highly monodisperse silica submicrospheres (SiO2), SiO2 with Chloro- functional group (SiO2-Cl), and silica-g-poly(methyl methacrylate) submicrospheres (SiO2-g-PMMA) have been discussed. At first, diameter of 158 to 700 nm were prepared by Stöber method. Three dimensional photonic crystals (PCs) were obtained by self- assembling of SiO2. Experimental λ max, obtained from UV Vis spectrophotometer, were consistent with photonic band gap (PBG), calculated from Bragg's Law, on 0° to 60°reflection angles. In other words, the structure color of PCs was corresponded to the PBG. Secondly, SiO2 was modified by (3-Chloropropyl) triethoxysilane (CPTS) to form Cl end-functional group on the surface (SiO2-Cl). The Chloro group was detected at about 198ev position by Electron Spectroscopy for Chemical Analysis (ESCA). Finally, SiO2-g-PMMA was obtained by atom transfer radical polymerization (ATRP) of SiO2-Cl in the presence of MMA using copper(I) chloride and N,N,N',N",N"-pentamethyldiethylenetriamine as catalyst precursors. The resulted showed that 5.6 % ~ 10.5 % grafted percentage of PMMA on SiO2-g-PMMA were characterized by Thermogravimetric Analyzer (TGA). In addition, 6 nm thickness of PMMA was observed by SEM and TEM. These results demonstrated that brush submicrospheres were synthesized successfully by ATRP. |
