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