@conference{
author = "Ivanovska, Aleksandra M. and Cerović, Dragana D. and Asanović, Koviljka A. and Kostić, Mirjana M.",
year = "2018",
abstract = "In order to obtain jute fabrics with high AC specific electrical conductivity, the raw jute
woven fabric was chemically modified. Namely, alkali modification with 17.5% NaOH at
room temperature for 5 and 30 min was performed for progressive removal of
hemicelluloses, while oxidative modification with 0.7% NaClO2 at boiling temperature for
15 and 60 min was used for progressive removal of lignin. The chemical composition of the
chemically modified jute fabrics was determined by successive removal of non-cellulosic
components, after that, the α-cellulose remains as a solid residue. The moisture sorption was
determined according to thermo-gravimetric method. As very important indirect indicator of
the tendency of the fibrous materials to generate static charge, AC specific electrical
conductivity was measured in the frequency region between 30 Hz and 140 kHz at 30%
relative air humidity.
After the alkali modifications, the content of hemicelluloses decreased from 21.76% for
unmodified to 12.34% for alkali modified jute fabric, while after the oxidative modifications,
the content of lignin decreased from 13.48% for unmodified to 4.98% for oxidative modified
jute fabric. The moisture sorption of the alkali modified jute fabrics is about 21.6-26.6%
higher compared to the unmodified jute woven fabric. Oxidative modification of jute fabrics
slightly increased their moisture sorption (3.2-12.5%). Since, the fabric is heterogeneous
three-phase system, it was suggested to refer it as the capacitance of “fiber-moisture-air”
system. In that context, the AC specific electrical conductivity is very sensitive to fabrics
chemical composition and moisture sorption. The lowest AC specific electrical conductivity
was noticed for the untreated jute fabric, which can be related to its highest content of
hemicelluloses and lignin and the lowest moisture sorption. Chemically modified jute fabrics
have higher values of AC specific electrical conductivity compared to unmodified jute fabric.
For example, 36.6% lower content of hemicelluloses (modification with 17.5% NaOH for 5
min) in comparison with unmodified fabric resulted in increased value of AC specific
electrical conductivity from 0.095 µSm
-1
to 0.79 µSm
-1
(at around 140 KHz). Jute fabric with
37.7% lower content of lignin has lower value of AC specific electrical conductivity (0.7
µSm
-1
). The higher AC specific electrical conductivity of alkali modified jute woven fabrics
can be explained by the presence of water in form of moisture, leading to increase the
number of the polar groups, which facilitate the flow of current through the amorphous
regions, as well as the crystallite’s surface regions.
The obtained jute fabrics with higher AC specific electrical conductivity can be successfully
used for protective clothes or textile of specific behavior in environments sensitive to electrical discharges, home textiles (carpet), filters (static charge causes impairment of
filtering properties as well as the fire risk that can be caused by the spark appearance), etc.",
publisher = "Belgrade : Institute of Technical Sciences of SASA",
journal = "Program and the Book of Abstracts / Seventeenth Young Researchers' Conference Materials Sciences and Engineering, December 5-7, 2018, Belgrade, Serbia",
title = "The influence of the chemical modifications on the AC specific electrical conductivity of the jute woven fabrics",
pages = "33-32",
url = "https://hdl.handle.net/21.15107/rcub_technorep_6797"
}
