Novel HDPE nanocomposites containing aluminum nitride (nano) particles: Micro-structural and nano-mechanical properties correlation

Abstract

The inclusion of inorganic nano-fillers with high mechanical strength in polymers could enhance efficiently the nano-mechanical properties of polymer-matrix (nano) composites. In this article, low-cost, high mechanical strength and stable crystal structured Aluminum nitride (nano) particles were incorporated into a High-density polyethylene (HDPE) thermoplastic polymer-matrix fabricated by melt-blending, compression moulding followed by hot pressing for investigation of nano-mechanical properties of HDPE/AlN nanocomposites. Nano-mechanical properties of HDPE/AlN (nano) composites (0-20 vol%) were measured by Quasi-static nanoindentation technique. A standard Berkovich indenter was used to make indentations under four different normal loads viz., 700, 1000, 3000 and 5000 μN, respectively. The surface topographies of the indented regions were monitored by AFM. The micro-structure of AlN (nano)/HDPE composites were characterized by intermittent tapping mode AFM, XRD, FEG-SEM and HR-TEM. The results showed that the homogenous distribution of AlN (nano) particles in the HDPE polymer-matrix affected the nano-mechanical properties of AlN (nano)/HDPE composites significantly. Nano-mechanical properties of the composites display substantial improvement with increasing AlN (nano) content in HDPE. The results are discussed with reference to AlN (nano) particles dispersion, interfacial adhesion and effective load transfer in AlN (nano) particles filled HDPE polymer composites.