Polyaniline Composite Conductive Coating

In this paper, a series of polyaniline (PANI) doped by different sulfonic acids, were synthesizd by two methods: in-situ chemical oxidative polymerization and chemical oxidative polymerization at sub-zero temperature, and the following composites were achieved by mixing epoxy resin and PANI-ABSA by ultrasonic oscillator. The mechanic properties and electrical behaviors of polyaniline were investigated. Also, the dispersion of polyanilinein the matrix and the distribution of main elements in surface were analyzed by SEM and XPS. Morphology and performance of polyaniline/resin composites influenced by the oxidative methods and doped ions, as well as the thermal stability were discussed.The polymerization of aniline to polyaniline was carried out by chemical oxidative polymerization of aniline using ammonium peroxydisulphate as oxidant at -25℃. After emeraldine base achieved, the polymer was "second-doped" with a specific ratio solution of methyl sulfonic acid (MSA), p- toluenesulfonic acid (TSA), p-amimobenzenesulfonic acid (ABSA), dodecylbenzene sulphonic acid (DBSA), camphor sulfonic acid (CSA). The modulus and the rigidity of the polyaniline were affected by the doped ions. Nevertheless, in the resins, the change could be neglected, for the content of polyaniline was so little.Then, the acids impacted on the electrical values and percolation threshold. Under the similar conditions, PANI-ABSA could achieve the higher surface electricity, but also with higher percolation threshold.The percolation threshold was connected with the dispersion of PANI particle.Referring to an acid, Morphology and performance of PANI particle varied with the method of polymerization. The results suggested that the compatibility of PANI and the matrix was better with in-situ chemical oxidative polymerization, whereas, the properties of product of chemical oxidative polymerization at sub-zero temperature were better (except ABSA).PANI/EP composites presented good thermal stability independent of synthetic method, above 350℃.It was concluded that PANI/EP composite had good environmental stability, well electricity and lower percolation threshold. Although the research on the polymer just began, PANI had potential application values.