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Abstracts ICPS 2023

 
 


Poster presentation 
307 
ELECTROSPINNING OF NANOFIBERS FROM Bombyx mori 
CHITOSAN SOLUTIONS 
 
R.Yu. Milusheva, K.K. Pirniyazov, S.Sh. Rashidova 
Institute of Polymer Chemistry and Physics of ASRU, Tashkent, Kadyri St., 7, b 
The development of functional materials from renewable sources (silk production 
waste) is an urgent task. The production of nanofibers based on chitosan is a new 
direction in the field of nanotechnology, since their production differs significantly in 
key parameters. Different feedstocks (chitosans from heterogeneous sources) lead to 
spinning solutions with different characteristics, which naturally leads to differences in 
the resulting nonwoven nanofiber materials. 
The electrospinning of nanofibers was carried out on an ES-robot Electrospinning 
/spray system with chitosan solutions of various concentrations. The electric field 
voltage was 25–28 W, the distance between the anode and cathode was 10 cm. The 
solution supply rate was controlled in the range from 2 to 20 μl/min. To obtain 
nanofibers, purified chitosan was obtained of preliminary dissolution of chitosan in 2% 
acetic acid, precipitation and coagulation of the solution at a certain pH, washing with 
alcohol, centrifugation, and freeze-drying of the sample. 
A sample of purified chitosan with Mv 184 kDa and SDA=84% was obtained. Bombyx 
mori solutions of various concentrations of chitosan in 80% acetic acid were prepared for 
electrospinning. IR spectroscopic and X-ray studies of the obtained nanofibers were carried 
out (Fig. 1,2). 
Fig. 1. - IR spectra of chitosan Vm and 
nanofibers based on it (Blue - nanofibers, red - 
original) 
Fig. 2. - Diffraction pattern of chitosan Vm and 
nanofibers based on it (Blue - nanofibers, red - 
original) 
The IR-spectrum of nanofibers of chitosan Bm differs from the initial spectrum of chitosan 
Bm, which may be due to the conditions for the formation of nanofibers, since during 
electrospinning of chitosan solutions, orientation of macromolecules occurs. Changes in the 
crystallinity and polymorphism of chitosan lead to slight differences in the absorption 
intensity in the absorption bands at 1604 cm-1 and 1592 cm-1. In nanofibers, a narrower 
absorption band at about 3500 cm–1 is observed, which confirms the partial participation of 
hydroxyl groups in the C2 and C6 positions of chitosan in intra- and intermolecular hydrogen 
bonds.The diffraction patterns of Bombyx mori chitosan show crystalline reflections with 
maxima at 2θ=5.79o, 10.52o, 20.3o and 28.9o. At the value of the angle 2θ=20.3°, the most 
intense maximum is observed, which refers to the crystallographic reflection (020). In this 
case, an amorphous halo is observed in the diffraction patterns of nanofibers, as well as broad 
crystalline reflections of the corresponding imperfect crystals. Thus, the IR and X-ray 
diffraction patterns of the obtained samples unambiguously indicate the formation of 
nanofibers under these conditions with the observed differences in the IR spectra and 
diffraction patterns. 
F:\BAZA DANI\Baza dani- 2022\NanoTola 17.08.2022\Нанотола 17,08,2022.0 Нанотола 17,08,2022 Poroshok
F:\BAZA DANI\Baza dani- 2022\Pirniyazov (oчиш XZ) 17,08,2022\Очиш. ХЗ для спиннинга.0 Очиш. ХЗ для спиннинга Poroshok
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