高分子刷結構可以改變界面或表面之物理性質，有效地提高固體之濕潤與黏著性、增強膠體穩定性與生物相容性。因此近年來高分子刷成為表面改質，以及奈米高分子材料領域的研究重點。本研究主要探討利用接枝到表面法(grafting-to method)在表面改質過的矽晶圓基材上合成不同密度的PEO高分子刷。 基材表面改質使用單一或混合兩種含矽原子的分子進行自組裝成單分子膜，此兩種含矽原子的分子分別為 3-mercaptopropyl trimethoxysilane (MPS) 和n-propyl triethoxysilane (PTS)。透過不同反應時間及濃度的差異造成MPS覆蓋率的差異，以決定表面改質的程度。藉由水接觸角和X射線光電子能譜儀 (X-ray photoelectron spectroscopy，XPS)判定表面改質的成果。高分子刷的合成是先將聚乙二醇(poly ethylene glycol，PEG)高分子的末端官能基從OH基換成Br基，藉由傅立葉轉換-紅外光譜儀(Fourier transform infrared spectroscopy，FT-IR)及超導核磁共振儀(Nuclear magnetic resonance，NMR)確認反應過後的高分子存在C-Br的鍵結。高分子上的Br末端官能基與MPS末端的SH官能基藉由鈀催化劑(bis (triphenyl- -phosphine) palladium(II) chloride，PdCl2(PPh3)2)進行C-S鍵耦合反應合成聚乙二醇高分子刷。我們可以透過水接觸角及X射線光電子能譜圖得知聚乙二醇的接枝情形。本研究說明了藉由簡單的表面改質技術達成合成高分子刷於自組裝單分子膜改質之基材進而達到改變表面性質以進行更多應用的目的。 Polymer brush can greatly modify the interface structure, physical, and chemical properties of the surface. Typical examples are manipulating the wetting and adhesion of solid, and enhancing colloidal stability and biocompatibility. Therefore, polymer brushes have become one of the most attractive research in recent years. This thesis reports the synthesis and applications of poly-ethylene-glycol (PEG) polymer brushes on surface-assembled monolayer (SAM)-modified silica substrates using grafting-to approach. The first part of the research focuses on the surface modification using SAMs. Two silane molecules, 3-mercaptopropyl trimethoxysilane (MPS) and n-propyl triethoxysilane (PTS) were used, to generate a monolayer of mixed SAMs onto silica substrate, with various MPS surface coverage. Water contact angle and X-ray photoelectron spectroscopy (XPS) were used to analyze the modified surface properties. PEG polymers with hydroxyl group at one end were used as the model system to study the properties of polymer brushes using grafting-to approach. First, -OH was replaced by -Br by adding PBr3 in the reaction. The -Br end-group was detected by Fourier transform infrared spectroscopy (FT-IR) and Nuclear magnetic resonance (NMR). Since MPS has an end -SH group, PEG with end -Br group can graft onto MPS through C-S coupling with the catalyst, bis (triphenylphosphine)palladium(II) chloride (PdCl2(PPh3)2). We can use water contact angle measurement ,XPS and AFM to check the polymer brush’s grafting statues. This study demonstrates that we can change the surface property via simple surface modification and polymer brush grafting technique.
