Surface functionalization of polymer substrates and nanoparticles via pulsed plasma polymerization process
This thesis investigates the RF plasma polymerizations of chlorinated saturated linear monomer 1,1,1-trichloroethane and the dicarboxylic citraconic acid. It utilizes a variable duty cycle plasma technique to provide film chemistry control during the plasma polymerization process. Film chemical compositions and deposition rates were characterized as functions of the plasma processing conditions. In each system studied, spectroscopic analyses revealed that large progressive changes in film compositions were obtained with sequential variations in plasma duty cycles in the plasma polymerization of both 1,1,1-trichloroethane and citraconic acid.
The plasma approach was also employed to modify the surfaces of nanoparticles. Thin polymeric films, produced from allylamine monomer, were pulsed plasma polymerized onto surfaces of 35nm (average particle size) gamma iron oxide nanoparticles. The morphology, structure and composition of the allylamine coated gamma iron oxide nanoparticles were characterized using a variety of analytical techniques. High resolution transmission electron microscope measurements revealed an ultra thin film of allylamine (4 nm) was uniformly deposited on surfaces of gamma iron oxide nanoparticles by the pulsed plasma polymerization process. Fourier transform infrared, X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectroscopy measurements all confirmed the allylamine deposition and existence of free amine groups on gamma iron oxide nanoparticle surfaces. The free amine groups of polyallylamine provide sites for immobilization of foreign molecules, suggesting that the allylamine coated gamma iron oxide nanoparticles can be employed to deliver drugs to targeted tissues and organs using magnetic focusing techniques.