Preparation and characterisation of nanocellulose reinforced polyamide-6

A procedure is described for preparing polyamide-6 (PA-6) reinforced with cellulose nanofibres. The cellulose nanofibres were obtained from flax and microcrystalline cellulose (MCC) using combinations of acid hydrolysis, ball milling and ultrasound, then characterised by transmission electron microscopy (TEM) in order to determine their size and geometry. The nanofibres produced from the different feedstock sources were of a similar order with lengths ranging from 21 to 300 nm and diameters between 2 and 22 nm. PA-6 nanocomposite films were subsequently prepared from these nanofibres using a solution casting technique. Their chemical and physical structure was analysed using Fourier transform infrared analysis (FTIR) and TEM. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were also applied to compare their thermal properties with unfilled polymer. Dynamic mechanical thermal analysis and tensile measurements demonstrated a significant enhancement in mechanical properties was possible with a low addition of cellulose nanofibres to the polymer matrix.