Functionalized Halloysites for Epoxy Nanocomposite Applications

S. Zeng, C. Reyes, P. Rodgers, S. Wentworth, L. Sun
University of Connecticut, US

Keywords: halloysite, nanocomposite, epoxy, dispersibility

Summary:

Polymer nanocomposites have been extensively studied over the past few decades, and a wide range of applications have been developed based on their excellent performance. Halloysite nanotube (HNT), a type of naturally occurring aluminosilicate clay, has come into focus for study as a nanofiller to reinforce polymers. Herein, we report a new approach for modifying HNTs for the preparation of epoxy/HNT nanocomposites with improved stiffness and toughness. The hydroxylated HNTs (h-HNTs) from NaOH treatment was further modified by sodium dodecyl sulfate (SDS), leading to better colloidal stability as confirmed by zeta potential. With an addition of 5 phr of this SDS treated h-HNTs (HNTs-SDS) into epoxy matrix, the modulus and fracture toughness of epoxy/HNT-SDS nanocomposite was improved by 22% and 52%, respectively. The simultaneous improvements in both stiffness and toughness are believed owing to the significantly improved interface between epoxy matrix and HNTs after surface treatment.