Novel process for isolating fibrils from cellulose fibers by high‐intensity ultrasonication. II. Fibril characterization

Abstract

High-intensity ultrasonication with a batch process was used to isolate fibrils from several cellulose sources, and a mixture of microscale and nanoscale fibrils was obtained. The geometrical characteristics of the fibrils were investigated with polarized light microscopy, scanning electron microscopy, and atomic force microscopy. The results show that small fibrils with diameters ranging from about 30 nm to several micrometers were peeled from the fibers. Some fibrils were isolated from the fibers, whereas some were still on the fiber surfaces. The lengths of untreated and treated cellulose fibers were investigated by a fiber size analyzer. The crystallinities of some cellulose fibers were evaluated by wide-angle X-ray diffraction and Fourier transform infrared spectroscopy. The high-intensity ultrasonication technique is an environmentally benign method and a simplified process that conducts fiber isolation and chemical modification simultaneously and helps significantly reduce the production cost of cellulose nanofibers and their composites.

A review of extractions of seaweed hydrocolloids: Properties and applications

“…This method has been employed from laboratory-scale level to fullscale commercialized applications in food industry due to its incredible advantages such as more effective mixing and micro-mixing, faster energy and mass transfer, reduced thermal and concentration gradients, reduced temperature, selective extraction, reduced equipment size, faster response to process extraction control, faster start-up, increased production, and elimination of process steps [109]. This environmentally benign and cost effective method has successfully extracted highly purified fibrils/nanofibrils from cellulosic materials [81,110]. Although UAE method has been utilized in extraction of bioactive compounds from several marine algae or even non-hydrocolloids materials [81,94,95,111,112].…”

Characterization of Fibers from Pineapple's Crown, Rice Husks and Cotton Textile Residues

“…For RH fibers, it was observed peaks at 2θ = 15. assigned to the (1 10), (101) and (200) crystallographic planes of cellulose II 22,23 , besides the peaks of cellulose I, (Figure 3). Cotton fiber was mercerized during the pre-treatment in the textile industry and this could change the crystalline structure of the cellulose contained in the resulting RTF fibers.…”

Advanced Cellulosic Nanocomposite Materials

“…2), such as regenerated cellulose fiber (Lyocell fiber), pure cellulose fiber (TC40, 180, and 2500), microcrystalline cellulose (MCC), and pulp fiber, was developed Cheng et al, 2010a). HIUS produces very strong mechanical oscillating power (Abramov, 1998), which forms hydrodynamic forces of ultrasound to separate cellulosic fibrils in micro/nano scales.…”

“…The treated and separated fibrils in micro and nano scales by HIUS were investigated using polarized light microscopy, SEM, and AFM. The crystallinities of treated and untreated cellulose fibers were studied by Wide-angle X-ray diffraction (WAXD) and Fourier transform infrared spectroscopy (FTIR) (Cheng et al, 2010a). The temperature of water suspension during HIUS treatment changes with different powers and cooling methods.…”