Morphology, structure and property of high consistency mechano-enzymatic fibrillated cellulose: Effect of treatment consistency of bamboo pulp fibers

High consistency mechano-enzymatic fibrillation of cellulose fibers is a desirable approach to producing high solid fibrillated cellulose (HSFC) materials in a green fashion, which can reduce water consumption and lower logistic costs as well as carbon footprint. Here, we mainly investigated the effects of various treatment consistencies (15–45%) of bamboo pulp fibers during the mechano-enzymatic processing on the morphology, structure, and property of the resulting HSFC materials. The results revealed that the 35% treatment consistency was the most favorable for producing fibrillated cellulose materials comprising the most nanoscale fibrils, despite a small fraction of unfibrillated microfibril bundles existing. The fibrillated cellulose obtained at the 35% consistency had the highest water retention value, yielding a cast film with the highest mechanical performance. The 15% treatment consistency generated HSFC materials with the least degree of fibrillation, in which most were shortened yet micro-sized fiber fragments. Regardless of treatment consistencies, the HSFC materials almost retained cellulose crystallinity and thermal stability. The results suggest that mechano-enzymatic fibrillation at a suitable treatment consistency is crucial to producing the most highly fibrillated cellulose.