Synthesis and characterization of graphene oxide reinforced triphenyl pyridine-based polyimide composites having UV shielding and low k properties

Graphene oxide (GO) reinforced polyimide composites with low-k, improved thermal stability, surface behavior and UV shielding properties have been developed. A new 2,6-bis(4-aminophenyl)-4-(4-(octyloxy)phenyl)pyridine (PyDA) was synthesized and its molecular structure has been confirmed by FT-IR and H-1-NMR spectroscopy. Polyimide (PI) was prepared using pyridine-based amine and pyromellitic dianhydride and characterized. The varying weight percentages of (5, 10, 15 wt%) of GO have been reinforced into polyimide matrix to obtain nanocomposites and were characterized using TGA, XRD, SEM and TEM analysis. The thermal studies infer that the value of decomposition temperature (T-d) obtained for neat PI matrix and GO-PI composites are 453 degrees C and 520 degrees C respectively and the percentage char yield are 38.9% and 40.5% respectively. The value of water contact angle of PI matrix has been steadily raised with the increasing incorporation of GO in the PI matrix. The values of contact angle observed for neat PI matrix and 15 wt% of GO reinforced PI nanocomposites are 87 degrees and 98 degrees respectively. Similarly, the values of dielectric constant obtained for neat polymer matrix and 15 wt% GO reinforced polyimide nanocomposites are 3.9 and 2.1 respectively. Results obtained from the UV studies indicated that the GO reinforced PI possesses better UV shielding behavior.