Preparation And Electrochromic Properties Of Conductive Polymers With Multi-color Range

Electrochromic polymers can be prepared by means of a simple technological process and has high optical contrast.The advantages of electrochromic device based on electrochromic polymers include their low driving voltages and rapid response times.In addition,to improve their performances,it’s necessary to do molecular design.Electrochromic polymers can be used for smart windows,automatically dimming rearview interior mirrors and displays and so on.In this dissertation,electrochromic polymers poly(3,4-ethylenedioxythiophene),poly(3,4-dibromo thiophene)and polyaniline were chosen as the main materials,in order to develop their color range and electrochromic properties.Through color combination,dye doped and compositing photonic crystals and electrochromic polymers,the research work blow was undergoing:1.The composite of poly(3,4-ethylenedioxythiophene)(PEDOT)and poly(3,4-dibromo-thiophene)(PDBrTh)was prepared by two consecutive electrochemical polymerization.The results indicated that the film can change reversibly between deep-red,atrovirens,and black-blue,and the response time of the composite film was 10.57s and 2.13s.Our study has shown that the color combination of different electrochromic polymers can enrich the color range of electrochromic mateials.2.PEDOT doped with acid red G(PEDOT-ARG)are electrochemical polymerized,which switched from aubergine in the reduction state to light blue in the oxidized state,and the response time was 5.7s for the oxidation process and 5.4s for the reverse reduction process,in various dye concentrations and different polymerization times,we prepared PEDOT films doped with water-soluble fluorescence yellow dye(PEDOT-FY),which showed orange,green,purple,greenish-gray and aubergine and so on,with fast response times and long cycle lifes.This method developed a novel general route to prepare enriched color range of electrochromic films.3.The opal structured SiO2@PANI photonic crystal film was fabricated via electrochemical methods by using the resulted SiO2 opal as template.It was found that the color of SiO2@PANI film was bright and vibrant with a maximal contrast of 77%,which was superior to pure PANI film of 43%,and its response speed was faster.Monodisperse PS microspheres were synthesized by soap-free emulsion polymerization,then red,blue and purple opal films were obtained by a vertical deposition self-assembly method.The PS@PANI film was prepared by electrochemically synthesis of PANI by a galvanostatic method by templating colloidal crystals(peak reflectance 660 nm),which showed dazzling color,such as red,blue and green.The maximal contrast was 40%@655nm,and the switch times were 4.7s and 3.8s,in addition,this film showed much better cycle stability than pure PANI film.