Synthesis And Properties Of Many Provinces And Quinone High Dielectric Polymer

With the development of technology, the trend of the microelectronic systems is to become smaller and more integrated. In order to overcome the existing limits in semiconductor devices, meanwhile, to improve the ability of storing electrical energy and reliability in capacitors, more and more researches have been focused on materials with high dielectric constant, especially in the industries of semiconductor and electric components. And some polymers with high dielectric constant are attracting so much attention in and abroad for their advantages, such as light weight, simple technics and easily being large-scale.Polyacene quinine radical polymer (PAQR) possesses high dielectric constant and good stability, so it is a kind of important polymers of high dielectric constant. However, PAQR has hardly been used in practice for the severe conditions of synthesis, the huge dielectric loss and bad solubility as well as being hardly fusible. In this paper our research work includes the synthesis process of PAQR and the influence of different conditions to the dielectric properties of the polymer. Then two new anthraquinone monomers and modified PAQR are synthesized. The dielectric properties of modified PAQR are also studied.A kind of molten salt NaCl /AlCl3, rarely reported in the synthesis of polymer, is used to synthesize PAQR, which is compared with the one got in nitrobenzene. The structure and thermal stability of polymers have been studied as well as the dielectric constant. The results indicate that PAQR shows good thermal stability. The polymer synthesized in NaCl /AlCl3 exhibits huge dielectric constant which is over 10,000 when the frequency is 20Hz while the one of polymer synthesized in nitrobenzene is below 10.The dielectric constant of PAQR decreases rapidly as the frequency increases.Besides, two new kinds of anthraquinone monomers :1,4-bis(octyloxy)anthracene- -9,10-dione and 1,4-dibutoxyanthracene-9,10-dione are synthesized and characterized by FITR, H1NMR spectra and elemental analysis. Results of DSC and TG indicate melting points of two monomers are below 130℃and the 5% thermal decomposition temperatures are more than 200℃. At last the modified PAQR are obtained by step-growth condensation polymerization which the monomers react in nitrobenzene and then the unpurified products are dried and react in NaCl /AlCl3. The structure and thermal properties are characterized by FITR, TG. And the dielectric constant is studied, too.The modified PAQR still exhibit excellent thermal stability as the 5% decomposition temperatures are over 387℃. The maximum of dielectric constant is 100 at 20Hz, which is less than the one of unmodified PAQR. A class of modified polymer which is soluble in ethanol is obtained and the dielectric constant is around 1,9997 at 20Hz.The dielectric properties of PAQR and modified one can be explaned by the theory of nomadic polarization.