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Download or read book Mean Depositions Rates of the Polymerization of Polyaniline by Oxidative Chemical Vapor Deposition written by Connor J. Brok and published by . This book was released on 2020 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt: Conductive polymers have become an important area of research as they have a multitude of uses. The growing trend of "smart" devices has led to expanding uses for these materials. Since polyaniline's discovery as a conductive polymer in the 1960s, it has stayed as an important material due to its high electrical conductivity and tunability. Among different methods for synthesizing polyaniline, oxidative chemical vapor deposition (oCVD) has emerged as an important polymerization technique that is solvent free, using oxidant and monomer vapors to enable the step-growth oxidative polymerization of polyaniline. The polymer is grown on a temperature-controlled substrate and under mild vacuum conditions. This research shows the effect of substrate position, substrate temperature and reaction time on the rate of reaction during the oCVD polymerization of aniline using antimony pentachloride as the oxidant. This work found that the position of the substrate relative to the center of the deposition zone determines the consistency and rate of deposition on the substrate, with the position near the center showing the most polymer growth. The analysis of substrate temperature showed that rate decreased as temperature increased. This indicated that the rate was limited by the adsorption of oxidant and monomer onto the substrate instead of the intrinsic kinetics of the polymerization reaction. Lastly, the reaction time analysis was shown to yield complex rate behavior. There was an initial rise to a steady state growth rate. However, at lower temperatures, a second rise in rate was seen. It is believed that an autocatalytic reaction of polyaniline with the aniline monomer is occurring that caused this rise. This work highlighted new deposition behavior that has not been previously reported and will be important in understanding further to enable better control of the oCVD process for depositing conducting polymers like polyaniline.