Influence of chitin nanofibrils ultrasonic treatment on structure and properties of chitosan-based composite materials

Application of the Composite Fibers Based on Chitosan and Chitin Nanofibrils in Cosmetology

“…Figure 2 also shows microphotographs of the chitosan fiber ( Figure 2 c,d) and the composite fiber ( Figure 2 e,f) containing 0.5 wt.% chitin nanofibrils. As can be seen in Figure 2 e,f, the composite fibers have a denser homogeneous structure compared to the unfilled chitosan fiber ( Figure 2 c,d), which is probably due to the good compatibility of the chitin nanofibrils and chitosan macromolecules due to the similarity of their chemical structure, that was explored in detail earlier elsewhere [ 28 , 31 , 32 ]. Chitin nanofibrils introduced into the chitosan solution facilitate the appearance of a new spatial arrangement of the chitosan chains.…”

“…The degree of dispersion of nanoparticles depends on the dispersion method and the type of interaction between a polymer and a filler, which, in turn, is determined by the peculiar features of their chemical structures. In our previous works [ 28 ], the optimal method of ultrasound dispersion (v = 22 kHz, P = 630 watts, t = 10 min) and the best suitable concentration of chitin nanofibrils (0.3–0.5%) for preparation of composite fibers with good mechanical characteristics were selected.…”

“…A study of the effect of an ultrasonic field on the process of dispersion of the chitin nanofibrils showed that the power and frequency of longitudinal vibrations in an aqueous medium determine the parameters of the cavitation process [ 28 ]. A model calculation showed that at a field power of 196 W, the radius of the air bubble changes smoothly, without destruction; the process is close to isothermal, which allowed us to conclude that the initial temperature changes in the cavity were weak.…”

“…Chitin nanofibrils introduced into the chitosan solution facilitate the appearance of a new spatial arrangement of the chitosan chains. In the acidified aqueous solution, protonated chitosan chains preferably interact with functional groups located on the surface of rigid chitin nanofibrils and not with each other [ 28 ]. Our previous paper [ 33 ] presents a calculation performed by the molecular dynamics method.…”

“…Chitosan and composite fibers were prepared using chitosan purchased from Biolog Heppe GmbH (Landsberg, Germany) with molecular mass Mm = (1.64 − 2.0) × 10 5 and deacetylation degree DD = 92.4%. The aqueous dispersion of chitin nanofibrils (SRL Mavi Sud, Italy) (C = 20 mg/mL) was subjected to ultrasound treatment with the use of an IL10-0.63 dispergator (“Ultrasonic Technique–Inlab”, St. Petersburg, Russia) for 10 min [ 28 ]. Chitosan powder was added to the ultrasound-treated aqueous dispersion.…”