Effects of Heat Treatment Conditions on Microstructure and Mechanical Properties of Halloysite Nanotube (HNT) Filled Epoxy Nanocomposites

Abstract

Halloysite nanotubes (HNTs) are naturally occurring Kaolite group minerals having an aluminosilicate-layer in the form of nanotubes. The composites containing a nanofiller in the form of HNTs used as a reinforcement and an epoxy resin as a matrix is effectively fabricated by using polymer casting method incorporating dispersion strengthening by mechanical stirring action and specimens are prepared as per American Society for Testing and Materials (ASTM) standards. The functional nanofillers are effectively used to enhance the mechanical strength of the composite by restricting matrix disengagement movements. In this regard, 2the present work is carried out to evaluate the mechanical properties of the nanocomposites consisting of different Wt.% of HNTs effectively heat-treated at three temperatures viz. Room temperature (RT), 50°C and 70°C and varying in the range of 0 to 10 with an interval of 5. The various properties viz. "density, hardness, tensile, flexural, and impact strength" are investigated through the ASTM procedure. As per the experimental investigation, the mechanical properties of the nanocomposite increases by the incorporation of heat-treated HNT. Further, the study revealed that the 10 Wt.% of HNT with 50°C heat-treated nanocomposite shows superior tensile and flexural strength. However, the critical observation of the results reveal that the impact strength is maximum for 70°C heat-treated nanocomposite synthesized for 5 Wt.% of HNT. It is evident that the properties of the nanocomposite depend on the quantity of functional filler present and temperature of heat treatment.