Grafting the Pattened Poly(2-dimethylaminoethyl methacrylate)-Quantum Dots Composite Brushes via Surface-Initiated Atom Transfer Radical Polymerization with pH Responsive Property

Autor: Hui-Hao Chen, 陳暉豪
Rok vydání: 2016
Druh dokumentu: 學位論文 ; thesis
Popis: 104
In this study, we divide into two parts, First, we grafted Poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) brushes from the initiator-modified surface of patterened silicon wafer by Atom Transfer Radical Polymerization (ATRP). After the reactions finish, we can use Fourier Transform Infrared Spectroscope (FTIR), X-ray photoelectron spectroscopy (XPS), Field Emission Scanning Electron Microscope (FE-SEM) and Contact Angle System (CA) to analyze the surface of polymer brushes. One-dimensional grating of the polymer brushes on the silicon wafer with the different widths are 1, 1.5, 2, 3μm. Using Atomic Force Microscope (AFM) to investigate the relationship between polymerization time and thickness. The highest thickness is 457nm. Polymer brushes are stimuli-responsive, they will swell and collapse when environment changes. When pH value is 4, 7 and 10, the highest thickness is 1323nm, 831nm and 783 nm, because of the positive repulsive force. There are almost double or triple changes of thickness, so we can use the characteristics in grating sensor. Furthermore, we immobilize quantum dots (CdTe) on the PDMAEMA brushes, and then use UV-vis light to make fluorescent pattern. After we finish the reaction, we use Field-emission transmission electron microscope (FE-TEM), Spectrofluorometer (PL), Ultraviolet-visible spectroscope (UV-Vis) and X-ray Diffractometer (XRD) to analyze quantum dots. Then using Confocal Laser Scanning Microscopy (CLSM) captures the different widths of fluorescent patterns, and find that CdTe was bound to the patterned PDMAEMA brushes.Observing switch of polymer brushes between different pH value by Atomic Force Microscope (AFM).
Databáze: Networked Digital Library of Theses & Dissertations
Externí odkaz: