Tailoring electrical and thermal properties of polymethyl methacrylate-carbon nanotubes composites through polyaniline and dodecyl benzene sulphonic acid impregnation

A series of composites of polymethyl methacrylate (PMMA) with polyaniline-multiwalled carbon nanotubes (PANI-CNTs) as filler I and dodecyl benzene sulphonic acid-multiwalled carbon nanotubes (DBSA-CNTs) as filler II are developed by solution mixing method. Composites are characterized for morphological, electrical, and thermal properties to study effect of two different types of additives, PANI, and DBSA. Furthermore, their influence on dispersion of CNTs is also studied. Electrical percolation behavior of both composites series is investigated through dielectric and conductivity measurements. Sharp insulators to conductor transition curves are obtained for filler I and II, with conductivity of 5.6 Scm(-1) at 2 wt% of CNTs and 2 Scm(-1) at 3 wt% of CNTs, respectively. High dielectric constant is observed for filler I as compared to filler II due to the formation of comparatively big clusters of filler I than II. Theoretically calculated percolation threshold was found to be 1.3 wt% for filler I and 0.8 wt% for filler II in the matrix with exponent constants 2.4 and 1.25, respectively. Thermal stability of PMMA composites, containing filler II, indicated an impressive increase by 72 degrees C onset and 55 degrees C in complete degradation temperature as compared to pure PMMA. POLYM. COMPOS., 39:E1052-E1059, 2018. (c) 2017 Society of Plastics Engineers