Facile fabrication of polycaprolactone/h-MoO3 nanocomposites and their structural, optical and electrical properties

Hexagonal molybdenum oxide (h-MoO3) nanocrystals with a flower-like hierarchical structure were successfully incorporated into polycaprolactone (PCL) matrix by a simple solution casting technique. Initially, the PCL was prepared by a catalytic ring-opening polymerization (ROP) of epsilon-caprolactone (epsilon-CL) under solvent free condition. Thiosemicarbazide and 4-phenylthiosemicarbazide based metal (Zn2+ and Cu2+) complexes were prepared and employed as catalysts for the ROP of epsilon-CL. The catalytic reaction conditions were optimized in detail. The resultant PCL was used to fabricate the PCL/h-MoO3 nanocomposites. The h-MoO3 with three different weight percentages (1, 3 and 5 wt%) was chosen. The structural, functional and morphological properties of nanocomposites were investigated by various spectroscopic and microscopic techniques. The merit of the PCL/h-MoO3 nanocomposites was realized from the improved AC conductivity, dielectric and optical properties compared to the pure PCL.