Cellulose I can be irreversible transformed into cellulose II via mercerisation or regeneration treatments.
In the past few decades, mercerisation was used mainly to improve fibre properties for textile industries.
A few studies have focused on the effects of mercerisation treatment on the cellulose polymorph itself
and after it was downscaled to nanosize. This study aims to characterise the micro size crystalline
cellulose after complete polymorph conversion via mercerisation technique and investigate its effects
on isolation to nanosize crystalline cellulose. A microcrystalline cellulose (MCC) was purchased and
converted into cellulose II via mercerisation technique. Sulphuric acid hydrolysis was carried-out
to produce nanocrystalline cellulose (NCC). The MCC and NCC of different polymorphs were then
characterised and analysed for its crystallography, morphology, particles size distribution and thermal
stability using wide-angle X-ray diffraction (WXRD), electron microscopes, dynamic light scattering
analyser and thermogravimetric analyser, respectively. Both MCC and NCC fibres showed complete
conversion of cellulose I to cellulose II and decrement of crystallinity index (CI). Electron micrographs
revealed that both cellulose II polymorph fibres (MCC II and NCC II) were morphological affected.
The analysis of size distribution and dimension
measurement confirmed that mercerisation
treatment causing increment in fibre diameter and
shortened length. The thermal stability of both
cellulose II polymorph fibres (MCC II and NCC
II) was also found to be improved.