The effect of reduction methods and stabilizer (PVP) on the properties of polyacrylonitrile (PAN) composite nanofibers in the presence of nanosilver

Abstract

There are many studies which use different types of reduction methods that affect the final properties of composite material containing silver nitrate (AgNO 3 ). The use of poly(N-vinylpyrrolidone) (PVP) in the composite also affects the final properties of composite material. However, as seen from the literature, it is difficult to find any studies focusing on polymer composite nanofibers reduced using different reduction methods and studies with different PVP loadings which are compared to each other, although it is very important to determine the most suitable reduction method and PVP loading for final composite properties. Thus, in this work, the effect of different reduction methods on polyacrylonitrile (PAN) composite nanofibers incorporating AgNO 3 and the comparison of different amounts of stabilizer (PVP) are studied in detail to determine the most suitable reduction method and the effect of PVP loading on the structure and the properties of the final product. PAN composite nanofibers having different amounts of PVP are reduced by four different methods namely arc-sol method, hydrazine method, arcweb method, and reflux method and characterized by electrical conductivity, mechanical testing, and thermal and SEM analyses. It has been observed that the hydrazine method provides higher breaking strength, electrical conductivity, enthalpy, smallest diameter, and lower cyclization temperature (T c ) than other reduction methods. Presence of PVP results in an increase of breaking strength and cyclization temperature, a decrease of enthalpy and the electrical conductivity. While highest breaking strength was obtained by hydrazine reduction with highest PVP loading, highest electrical conductivity was obtained by hydrazine reduction without PVP. As a direct result of the incorporation of AgNO 3 with or without PVP, insulator pure PAN (10 -12 S/cm) becomes semi-conductive material (10 -7 S/cm), which can be used as an antistatic material.

Polyacrylonitrile-polyaniline composite nanofiber webs: Effects of solvents, redoping process and dispersion technique

“…The tester was equipped with a 100 N load cell and the testing was performed at a crosshead speed of 20 mm/min [18,[38][39][40]. The length and width of the specimens were 35 mm and 5 mm, respectively.…”

“…The length and width of the specimens were 35 mm and 5 mm, respectively. The gauge length was 15 mm [18,39,40]. At least 10 specimens were tested for each sample and average value for the sample was calculated.…”

Polyacrylonitrile/polyaniline composite nanofiber webs with electrostatic discharge properties

“…11,[38][39][40] The length and width of the specimens were 35 mm and 5 mm, respectively. The gage length was 15 mm, and at least 10 specimens were tested for each sample.…”

“…The gage length was 15 mm, and at least 10 specimens were tested for each sample. 11,39,40 The thicknesses of the specimens were measured with a Mitutoyo digital micrometer.…”

Nanocomposite polyacrylonitrile filaments with electrostatic dissipative and antibacterial properties

“…They investigated the nanowebs regarding their morphology, crystallinity, silver ion release and antibacterial activity, and reported excellent antibacterial activity. [14][15][16][17][18][19][20][21][22][23][24] Considering the results of above composite nanofiber web studies, the addition of AgNO 3 to PAN microfilament produced by wet-spinning method and performing chemical reduction process is also a very promising technique for the production of nanocomposite antibacterial filaments. However, there are very limited number of studies in literature.…”