Evaluation of micro and Nano-fibers produced from old corrugated container (OCC) fibers by super disk grinding method

Cellulose Nano-fiber (CNF) and lignocellulose Nano-fiber (LCNF) are the most abundant bio-Nano-polymers that attracted much attention in researches and applications during recent decades. Super disk grinding method has prominent characteristics compared to the other methods such as simplicity, high speed, and high yield of production and owning single-stage process.

In this study, old corrugated container (OCC) was converted to lignocellulose microfibers (LCMF) and LCNF. LCNF was produced with ultra-fine friction grinding process, as a simple, fast and one-step downsizing method. The objective of this study was to investigate the grinding method on morphological characteristics (fiber diameter and distribution) with field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectrometry (EDX/EDS) analysis, thermal gravimetric analysis (TGA), suspension stability and air permeability of films made from LCMF and LCNF.

The average diameter of LCMF and LCNF obtained was 37±10 µm and 66±10 nm, respectively. The suspension of LCMF was unstable over checking stability time (after 2 min.), while the LCNF suspension had a long-term stability. The air-permeability of LCMF and LCNF films was 42.6 and 1.26 µmPa-1s-1, respectively. With downsizing lignocellulose fibers from micro to Nano scale, specific surface and bonding area increased and higher uniformity and lower porosity obtained.

In general, the results of this study showed that the production of LCNF and its film from OCC pulp were succeeded. Further investigations on the production of LCNF and evaluation its potential to produce different products compared to CNF (free of lignin and hemicelluloses) can bring many practical and industrial benefits to further commercialization of this value-added product.