Properties of Waterborne Polyurethane/CNT Nanocomposite Adhesives: Effect of Countercations

Abstract

Two series of waterborne polyurethane (WBPU)/carbon nanotube (CNT) nanocomposites were prepared with various CNT contents (0-1.50 wt%). We used a metal-hydroxide (copper hydroxide, Cu(OH)(2)) and amine (triethylamine, TEA) as the countercation in the nanocomposites. The interaction of the counter-cations with the CNTs in the nanocomposite was characterized by TEM, and the interaction effects on the properties, such as the glass transition temperature (T-g), storage modulus, tensile strength, Young's modulus and adhesive strength, were investigated. The CNTs were homogeneously (optimum) dispersed at concentrations of up to 1.25 and 1.00 wt% for the metal-hydroxide and amine series, respectively. At the optimum CNT content, the tensile strength and adhesive strength were maximized in each series. However, the adhesive strength of the WBPU/CNT nanocomposite with the metal-hydroxide countercation was less affected than with the amine-countercation after immersing the adhesive bonded nylon fabrics in water (for up to 48 h). (C) Koninklijke Brill NV, Leiden, 2011