Cellulose nanofibres offer potential as a cheap source of nanofibres for use in nonwovens and composites. Cellulose nanofibres have been produced by electrospinning and by grinding fibres from wood and other ligno-cellulosic species. In this study, cellulose nanofibres were prepared from a bleached northern softwood kraft (NIST RM 8495) by a process of wet disintegration to separate the dried fibres from each other. This was followed by mechanical treatment in a laboratory refiner and separation using a 200 mesh screen. Mechanical treatment to achieve pulp drainage characteristics similar to those used industrially in the manufacture of paper produced a yield of around 5% nanofibres. SEM images of the resulting fibres show a broad range of fibre sizes, due to the probabilistic nature of the separation process, but most fibres appear to have diameters in the range of 50-100 nm. The remaining 95% of the fibres retained on the screen are suitable for the production of conventional paper. The method shows the potential for generating cellulose nanofibres as by-products from paper manufacture, since variations of all the processing steps used in this work are also currently used in paper manufacture.

The nanofibres were formed into nonwoven sheets from a 0.5% (wt/v) suspension of solids using a woven filter under vacuum. The nonwoven sheets had extremely low porosity, natural resistance to moisture penetration and were stronger than conventionally produced paper. These nonwoven products show great potential as very fine particle filters, coatings and materials for applications such as tissue engineering.