Influence of surfactant assisted exfoliation of hexagonal boron nitride nanosheets on mechanical, thermal and dielectric properties of epoxy Nanocomposites

Abstract

ABSTRACTIn Present decade, polymer nanocomposites are extensively used for manufacturing of automotive, aircraft structural components. The polymer nanocomposites properties enhancement depends upon dispersion quality of nanofiller. Recently, hexagonal boron nitride (hBN) nanosheets is one of the most attractive nanofiller; a white solid with a layered structure, physically or structurally similar to graphite, also known as White graphene. In the present work, the hBN nanosheets are prepared by surfactant assisted liquid-phase exfoliation method using ethanol as solvent. The surfactant used is a block copolymer of polyethylene oxide-polypropylene oxide-polyethylene oxide (PEO-PPO-PEO). Although ethanol is a poor solvent, but it is a green solvent. A highly concentrated and stable dispersion of hBN nanosheets (~0.45 mg/ml) is obtained by probe sonication followed by centrifugation. The surfactant modified hBN nanosheets reinforced epoxy nanocomposites are prepared by an open casting method and characterized by various characterization techniques. At 0.08 wt% of surfactant modified hBN nanosheets incorporation in epoxy matrix show enhancement in flexural modulus and strength is by 3.6% and 5.7%. There is a multilayer dispersion of surfactant modified hBN nanosheets in epoxy matrix facilitating the dampening of cracks for flexural properties enhancement.