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Ганиев Парпиев тўплам 1 ҚИСМ 25 05 2022

Adabiyotlar roʻyxati 
1.Nasimov A, Buronov A, Isakulova M, Toshpulatov D, Mirzayev Sh. Tashpulatov Kh, 
Photochemical studies of bromocresol purple in sol-gel membrane, Jour of Adv Research in 
Dynamical & Control Systems, Vol. 12, 04-Special Issue, 2020, 1156-1159 pp 
2.M. Medina-Sa´nchez, S. Miserere, A. Merkoc¸i, Nanomaterials and lab-on-a-chip 
technologies, Lab Chip 12 (2012) 1932-1943. 
OXIDATION OF MICROCRYSTALLINE CELLULOSE BY 
POTASSIUM PERMANGANATE 
Kuzieva M., Axatov A., Ataxanov A. 
Institute of Polymer Chemistry and Physics, Uzbekistan Academy of Sciences, Tashkent, 
Uzbekistan. 
 
In recent years, nanocellulose materials have been widely used to produce 
specific materials with properties such as biocompatibility, biodegradability, and low 
toxicity. Oxidized nanocellulose (ONC), which has been used in the biomedical and 
pharmaceutical applications due to their biodegradable, biocompatible, haemostatic, 
and antibacterial properties [1]. 
The aim of this work was to study the oxidation of microcrystalline cellulose in 
the presence of potassium permanganate in an acidic medium and study the 
properties and structures of the resulting ONC (Figure 1). 
Figure 1. 
Reaction of MCC oxidation 
The formation of carboxyl groups was also confirmed by IR spectroscopic 
studies. Comparative studies of MCC and ONC showed that absorption bands at ~ 
3400 cm
-1
are observed in the IR spectra, which are related to the stretching 
vibrations of O-H. In the case of ONC, this absorption band narrows and appears 


316 
more intensely due to a decrease in the number of hydroxyl groups involved in 
hydrogen bonds. The stretching vibrations of the CH bonds in in methylene and me 
thine groups are manifested in the regions of 2800-2950 cm
- 1
. In contrast to the 
spectrum of the MCC samples, a new absorption band appears in the spectra of ONCs 
at 1721 cm
-1
, which is related to the stretching vibration C=O, confirming the 
presence of carboxyl groups [2]. At the same time, in the region of 1425 cm
-1
related 
to bending vibrations of -CH
2
- groups, the signal intensity decreases, and the 
intensity of the absorption band at 1315 cm
-1
related to fan-shaped vibrations of -
CH
2
- groups, which are associated with out-of-plane vibrations, increases. The 
pyranose ring of the elementary cellulose unit is preserved, which confirms the 
oxidation of the C6 hydroxyl group. 
The calculation of the conductometric titration results showed that the amount of 
carboxyl groups 1,1 mmol/g. 
The sizes and distribution of particles were estimated by the DLS method, which 
showed that the sizes of particles ranged from micrometers to nanometrs, and a 
polymodal distribution of particles was also observed. The size of the ONC particles 
decreases with an increase duration of the oxidation process, which is in good 
agreement with the results of AFM studies. 
AFM studies showed that the ONC size was reduced to 106-180 nm, and the 
spherical shape of the MCC was partially eliminated. 
In summary, the possibility of MCC oxidation in a more accessible way under 
mild conditions using potassium permanganate in an acidic medium was shown. By 
using AFM and DLS was showed that the oxidation process leads to a decrease in the 
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