The aim of this research was to align poly(3-hydroxybutyrate) (PHB)-functionalised multi-walled carbon nanotubes (MWCNTs) into a chitosan matrix. The MWCNTs were first functionalised with PHB and aligned into a membrane filter template through a filtration process. A solution casting technique was then applied to cast the chitosan onto the template to form PHB-MWCNT/chitosan nanocomposite membranes. The functionalised MWCNTs and resulting membranes were characterised using thermo-gravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The TGA demonstrated that approximately 40 wt.% of the PHB was successfully functionalised in the MWCNTs, and TEM showed that the polymer wrapped on the nanotubes surface. The presence of the PHB functional moieties helped to improve the dispersion and compatibility of the MWCNTs in the chitosan matrix. When we applied the PHB-MWCNT/chitosan nanocomposite membranes in the pervaporation process of 1,4-dioxane dehydration, the nanocomposite membrane showed a relatively high permeation flux and selectivity towards water, compared to existing membrane. (c) 2010 Elsevier B.V. All rights reserved.