Synthesis of graft copolymers carrying molecular diffusion susceptibility; investigation of the thermal, electrical and self-healing properties

In this study, 4-vinyl benzyl chloride was first prepared by acylation with 2-bromoisobutyryl bromide on the hydroxyl group of its structure after the preparation of 4-vinylbenzylalcohol according to the method adapted from the literature. Copolymers of this monomer with styrene were prepared by free-radical polymerization method and used as macroinitiator in studies. In order to prepare a monomer with the amide side group, compounds containing the OH and NH2 functionals together and amide and OH ended structures prepared from the reaction of acetic anhydride were synthesized, and then monomers were prepared from their reactions with acryloyl chloride. Graft copolymers were prepared by the ATRP method by using the prepared copolymers as a macroinitiator. FT-IR, 1H and 13C-NMR techniques were used in the characterization of synthesized polymers. The thermal behaviors of the polymers were examined by DSC and TGA. Activation energies for the thermal degradation of the polymers were calculated according to Flynn-Wall-Ozawa method by using the TG curves at different heating rates. In thesis concept, the self-healing behavior was investigated from property of reversible hydrogen bonding in soft matrix in the multi-phase supramolecules. The graft copolymer was first divided into two parts in order to examine the self-healing feature and these two pieces were then brought together and held for one minute. The self-healing were performed using the SEM and DMA techniques at room temperature. The recovery percentages were estimated versus time from measurements. The dielectric behaviors of the copolymers were examined as a function of temperature and frequency. Poly[(4-(2-bromoisobutiroyl methyl)]styrene and poly(3-acetamidopropyl acrylate) homopolymers were prepared, and the dielectric properties of these polymers were investigated using different filler. The graphene-based composites were prepared in order to give semi-conductive properties to the pure copolymers prepared at our study. After analyzing the dc conductivity properties of these composites, current (I)-voltage (V) graphs were recorded for the composite system containing graphene in the highest ratio, and diode characterization was carried out. In addition, capacitance, series resistance and conductivity values versus voltage of polymer composites were investigated by a system integrated with the impedance analyzer.