TY  - JOUR
AU  - Lazić, Biljana
AU  - Janjić, Svjetlana
AU  - Ivanović, Vesna
AU  - Kostić, Mirjana
AU  - Novak, Bostjan
PY  - 2023
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/7301
AB  - Flax fibers contain cellulose and different impurities (hemicelluloses, lignin, pectin, waxes and fats, mineral salts, natural coloring matter and water soluble compounds). From the ecological and industrial aspect, hydrogen peroxide is the most acceptable component for modification of flax fibers. The aim of the modification of flax fibers is to remove non-cellulose components and improve the fiber quality without significant changing of the mechanical properties. Flax fibers were treated with hydrogen peroxide solutions at concentrations 1%, 2% and 4% at 50 °C, 80 °C and boiling temperature for time period of 60 min. With the removal of non-cellulosic substances from fibers, it has been achieved a high degree of fiber separation and a significant increase of modified fibers fineness. The value for fineness of modified fibers was reduced about 2-4-fold and the modified flax fibers were softer to the hand, unlike unmodified fibers that are very coarse and stiff. However, the weight loss and removal of lignin, which gives the fibers strength, as well as a partial damage of the cellulose itself during the severity of treatment, brought to reduction in the tensile strength of the modified fibers.
PB  - University of Banja Luka, Faculty of Technology
T2  - Journal of Chemists, Technologists and Environmentalists
T1  - Effect of hydrogen-peroxide treatment on the physico-mechanical properties of flax fibers
EP  - 19
IS  - 1
SP  - 14
VL  - 4
DO  - 10.59919/JCTE04202301E219
ER  - 

@article{
author = "Lazić, Biljana and Janjić, Svjetlana and Ivanović, Vesna and Kostić, Mirjana and Novak, Bostjan",
year = "2023",
abstract = "Flax fibers contain cellulose and different impurities (hemicelluloses, lignin, pectin, waxes and fats, mineral salts, natural coloring matter and water soluble compounds). From the ecological and industrial aspect, hydrogen peroxide is the most acceptable component for modification of flax fibers. The aim of the modification of flax fibers is to remove non-cellulose components and improve the fiber quality without significant changing of the mechanical properties. Flax fibers were treated with hydrogen peroxide solutions at concentrations 1%, 2% and 4% at 50 °C, 80 °C and boiling temperature for time period of 60 min. With the removal of non-cellulosic substances from fibers, it has been achieved a high degree of fiber separation and a significant increase of modified fibers fineness. The value for fineness of modified fibers was reduced about 2-4-fold and the modified flax fibers were softer to the hand, unlike unmodified fibers that are very coarse and stiff. However, the weight loss and removal of lignin, which gives the fibers strength, as well as a partial damage of the cellulose itself during the severity of treatment, brought to reduction in the tensile strength of the modified fibers.",
publisher = "University of Banja Luka, Faculty of Technology",
journal = "Journal of Chemists, Technologists and Environmentalists",
title = "Effect of hydrogen-peroxide treatment on the physico-mechanical properties of flax fibers",
pages = "19-14",
number = "1",
volume = "4",
doi = "10.59919/JCTE04202301E219"
}

Lazić, B., Janjić, S., Ivanović, V., Kostić, M.,& Novak, B.. (2023). Effect of hydrogen-peroxide treatment on the physico-mechanical properties of flax fibers. in Journal of Chemists, Technologists and Environmentalists
University of Banja Luka, Faculty of Technology., 4(1), 14-19.
https://doi.org/10.59919/JCTE04202301E219

Lazić B, Janjić S, Ivanović V, Kostić M, Novak B. Effect of hydrogen-peroxide treatment on the physico-mechanical properties of flax fibers. in Journal of Chemists, Technologists and Environmentalists. 2023;4(1):14-19.
doi:10.59919/JCTE04202301E219 .

Lazić, Biljana, Janjić, Svjetlana, Ivanović, Vesna, Kostić, Mirjana, Novak, Bostjan, "Effect of hydrogen-peroxide treatment on the physico-mechanical properties of flax fibers" in Journal of Chemists, Technologists and Environmentalists, 4, no. 1 (2023):14-19,
https://doi.org/10.59919/JCTE04202301E219 . .

TY  - JOUR
AU  - Lazić, Biljana D.
AU  - Janjić, Svjetlana
AU  - Rijavec, Tatjana
AU  - Kostić, Mirjana
PY  - 2017
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/3691
AB  - Flax fibers were modified with NaOH and NaClO2 under different conditions in order to not only clarify the effects of hemicelluloses and lignin removal on the morphology and properties of flax fibers, but also to improve the fiber quality. The quality of flax fibers was characterized in terms of chemical composition, fineness, whiteness, and mechanical and sorption properties. Both treatments, alkali treatment leading to hemicelluloses removal ( up to 72 %) and chlorite treatment leading to lignin removal ( up to 96 %), induce a modification of the morphology and properties of flax fibers. For 5 % NaOH treatments, as well as all NaClO2 treatments, an increase in the crystallinity was observed, while for higher NaOH concentrations, the mercerization phenomenon induced a slight decrease in the crystallinity. Modification with NaClO2 resulted in fiber fibrillation while modification with NaOH at boiling temperature resulted in smoother fiber surfaces. Both treatments cause a decrease in tensile strength and water retention values, with the maximal decrease obtained with NaOH treatment at boiling temperature. Chlorite treatment resulted in finer fibers having a higher whiteness index compare to the alkali-modified fibers.
PB  - Srpsko hemijsko društvo, Beograd
T2  - Journal of the Serbian Chemical Society
T1  - Effect of chemical treatments on the chemical composition and properties of flax fibers
EP  - 97
IS  - 1
SP  - 83
VL  - 82
DO  - 10.2298/JSC160707106L
ER  - 

@article{
author = "Lazić, Biljana D. and Janjić, Svjetlana and Rijavec, Tatjana and Kostić, Mirjana",
year = "2017",
abstract = "Flax fibers were modified with NaOH and NaClO2 under different conditions in order to not only clarify the effects of hemicelluloses and lignin removal on the morphology and properties of flax fibers, but also to improve the fiber quality. The quality of flax fibers was characterized in terms of chemical composition, fineness, whiteness, and mechanical and sorption properties. Both treatments, alkali treatment leading to hemicelluloses removal ( up to 72 %) and chlorite treatment leading to lignin removal ( up to 96 %), induce a modification of the morphology and properties of flax fibers. For 5 % NaOH treatments, as well as all NaClO2 treatments, an increase in the crystallinity was observed, while for higher NaOH concentrations, the mercerization phenomenon induced a slight decrease in the crystallinity. Modification with NaClO2 resulted in fiber fibrillation while modification with NaOH at boiling temperature resulted in smoother fiber surfaces. Both treatments cause a decrease in tensile strength and water retention values, with the maximal decrease obtained with NaOH treatment at boiling temperature. Chlorite treatment resulted in finer fibers having a higher whiteness index compare to the alkali-modified fibers.",
publisher = "Srpsko hemijsko društvo, Beograd",
journal = "Journal of the Serbian Chemical Society",
title = "Effect of chemical treatments on the chemical composition and properties of flax fibers",
pages = "97-83",
number = "1",
volume = "82",
doi = "10.2298/JSC160707106L"
}

Lazić, B. D., Janjić, S., Rijavec, T.,& Kostić, M.. (2017). Effect of chemical treatments on the chemical composition and properties of flax fibers. in Journal of the Serbian Chemical Society
Srpsko hemijsko društvo, Beograd., 82(1), 83-97.
https://doi.org/10.2298/JSC160707106L

Lazić BD, Janjić S, Rijavec T, Kostić M. Effect of chemical treatments on the chemical composition and properties of flax fibers. in Journal of the Serbian Chemical Society. 2017;82(1):83-97.
doi:10.2298/JSC160707106L .

Lazić, Biljana D., Janjić, Svjetlana, Rijavec, Tatjana, Kostić, Mirjana, "Effect of chemical treatments on the chemical composition and properties of flax fibers" in Journal of the Serbian Chemical Society, 82, no. 1 (2017):83-97,
https://doi.org/10.2298/JSC160707106L . .

TY  - JOUR
AU  - Janjić, Svjetlana
AU  - Kostić, Mirjana
AU  - Vucinić, Verica
AU  - Dimitrijević, Suzana
AU  - Mihajlovski, Katarina
AU  - Ristić, Mihailo S.
AU  - Škundrić, Petar
PY  - 2009
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/1426
AB  - The possibilities of obtaining biologically active cell ulose-chitosan fibers were examined. An effective two-stage method was developed. The first stage involves the formation of dialdehyde cellulose by the potassium periodate oxidation of lyocell fibers, which is able to form Schiff's base with chitosan. In the second stage, chitosan-coated lyocell fibers were prepared by subsequent treatment of oxidized lyocell fibers with a solution of chitosan in aqueous acetic acid. The impact of this two-stage protocol on the chemical and physical properties of lyocell fibers was evaluated by determining carbonyl group content, fineness and tensile strength of fibers, as well as chitosan content in the composite cell ulose-chitosan fibers. Antibacterial activity of the chitosan-coated lyocell fibers against different pathogenens: Staphylococcus aureus and Escherichia coli, was confirmed in vitro experiments.
PB  - Elsevier Sci Ltd, Oxford
T2  - Carbohydrate Polymers
T1  - Biologically active fibers based on chitosan-coated lyocell fibers
EP  - 246
IS  - 2
SP  - 240
VL  - 78
DO  - 10.1016/j.carbpol.2009.03.033
ER  - 

@article{
author = "Janjić, Svjetlana and Kostić, Mirjana and Vucinić, Verica and Dimitrijević, Suzana and Mihajlovski, Katarina and Ristić, Mihailo S. and Škundrić, Petar",
year = "2009",
abstract = "The possibilities of obtaining biologically active cell ulose-chitosan fibers were examined. An effective two-stage method was developed. The first stage involves the formation of dialdehyde cellulose by the potassium periodate oxidation of lyocell fibers, which is able to form Schiff's base with chitosan. In the second stage, chitosan-coated lyocell fibers were prepared by subsequent treatment of oxidized lyocell fibers with a solution of chitosan in aqueous acetic acid. The impact of this two-stage protocol on the chemical and physical properties of lyocell fibers was evaluated by determining carbonyl group content, fineness and tensile strength of fibers, as well as chitosan content in the composite cell ulose-chitosan fibers. Antibacterial activity of the chitosan-coated lyocell fibers against different pathogenens: Staphylococcus aureus and Escherichia coli, was confirmed in vitro experiments.",
publisher = "Elsevier Sci Ltd, Oxford",
journal = "Carbohydrate Polymers",
title = "Biologically active fibers based on chitosan-coated lyocell fibers",
pages = "246-240",
number = "2",
volume = "78",
doi = "10.1016/j.carbpol.2009.03.033"
}

Janjić, S., Kostić, M., Vucinić, V., Dimitrijević, S., Mihajlovski, K., Ristić, M. S.,& Škundrić, P.. (2009). Biologically active fibers based on chitosan-coated lyocell fibers. in Carbohydrate Polymers
Elsevier Sci Ltd, Oxford., 78(2), 240-246.
https://doi.org/10.1016/j.carbpol.2009.03.033

Janjić S, Kostić M, Vucinić V, Dimitrijević S, Mihajlovski K, Ristić MS, Škundrić P. Biologically active fibers based on chitosan-coated lyocell fibers. in Carbohydrate Polymers. 2009;78(2):240-246.
doi:10.1016/j.carbpol.2009.03.033 .

Janjić, Svjetlana, Kostić, Mirjana, Vucinić, Verica, Dimitrijević, Suzana, Mihajlovski, Katarina, Ristić, Mihailo S., Škundrić, Petar, "Biologically active fibers based on chitosan-coated lyocell fibers" in Carbohydrate Polymers, 78, no. 2 (2009):240-246,
https://doi.org/10.1016/j.carbpol.2009.03.033 . .

TY  - JOUR
AU  - Janjić, Svjetlana
AU  - Kostić, Mirjana
AU  - Škundrić, Petar
PY  - 2007
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/1029
AB  - The increased production of bast fibres (especially hemp fibres) brought about an increase in the amount of waste, namely shive (hemp stalks) and short fibres. This waste presents a potential significant source of high quality cellulose suitable for the production of high-quality papers and chemical cellulose fibres. The dissolution of hemp cellulose fibres in N-methylmorpholine-N-oxide (NMMO) was investigated. Hemp cellulose with an α-cellulose content of 88.3% and a DPη of 1100, obtained by previously removing fats, waxes, pectins, hemicelluloses and lignin from the hemp fibres, was used in these experiments. The cellulose concentration was varied from 1 to 10 wt.%. The dissolution and subsequent crystallization of the obtained solutions were observed using a hot-stage polarized light microscope. The rheological properties of the solutions of hemp and beech cellulose in NMMO were compared.
PB  - Taylor & Francis Inc, Philadelphia
T2  - Journal of Natural Fibers
T1  - Direct hemp cellulose dissolution in N-Methylmorpoline-N-Oxide
EP  - 36
IS  - 3
SP  - 23
VL  - 4
DO  - 10.1300/J395v04n03_02
ER  - 

@article{
author = "Janjić, Svjetlana and Kostić, Mirjana and Škundrić, Petar",
year = "2007",
abstract = "The increased production of bast fibres (especially hemp fibres) brought about an increase in the amount of waste, namely shive (hemp stalks) and short fibres. This waste presents a potential significant source of high quality cellulose suitable for the production of high-quality papers and chemical cellulose fibres. The dissolution of hemp cellulose fibres in N-methylmorpholine-N-oxide (NMMO) was investigated. Hemp cellulose with an α-cellulose content of 88.3% and a DPη of 1100, obtained by previously removing fats, waxes, pectins, hemicelluloses and lignin from the hemp fibres, was used in these experiments. The cellulose concentration was varied from 1 to 10 wt.%. The dissolution and subsequent crystallization of the obtained solutions were observed using a hot-stage polarized light microscope. The rheological properties of the solutions of hemp and beech cellulose in NMMO were compared.",
publisher = "Taylor & Francis Inc, Philadelphia",
journal = "Journal of Natural Fibers",
title = "Direct hemp cellulose dissolution in N-Methylmorpoline-N-Oxide",
pages = "36-23",
number = "3",
volume = "4",
doi = "10.1300/J395v04n03_02"
}

Janjić, S., Kostić, M.,& Škundrić, P.. (2007). Direct hemp cellulose dissolution in N-Methylmorpoline-N-Oxide. in Journal of Natural Fibers
Taylor & Francis Inc, Philadelphia., 4(3), 23-36.
https://doi.org/10.1300/J395v04n03_02

Janjić S, Kostić M, Škundrić P. Direct hemp cellulose dissolution in N-Methylmorpoline-N-Oxide. in Journal of Natural Fibers. 2007;4(3):23-36.
doi:10.1300/J395v04n03_02 .

Janjić, Svjetlana, Kostić, Mirjana, Škundrić, Petar, "Direct hemp cellulose dissolution in N-Methylmorpoline-N-Oxide" in Journal of Natural Fibers, 4, no. 3 (2007):23-36,
https://doi.org/10.1300/J395v04n03_02 . .

TY  - JOUR
AU  - Janjić, Svjetlana
AU  - Škundrić, Petar
AU  - Kostić, Mirjana
AU  - Lazić, Biljana D.
PY  - 2005
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/802
AB  - In recent years growing attention has been paid to production of cellulose from unconventional, annually and renewable plants such as hemp and flax. Lignin and pectin are very important noncellulosic substances occurring in hemp fibers. In order to establish effects on lignin removal, four types chemical processes are conducted: with boiling sodium hydroxide, with boiling sodium hydroxide and afterwards with permanganate; with boiling sodium hydroxide and afterwards with hydrogen peroxide; and with hydrogen peroxide. Lignin in hemp before and after chemical processing is characterized. The results indicate that the alkaline boiling process is effective for removing lignin and afterwards treatment with peroxide additionally removing lignin and also increase fiber whiteness. It is establish that, the cellulose obtained from hemp fibres by previous treatment is high quality materials for the process of manufacturing cellulose fibers based on direct cellulose dissolution in the N-methylmorpholine N-oxide (NMMO) as predominating technology for the 21st century.
AB  - Poslednjih godina je posvećena velika pažnja dobijanju celuloze od nekonvencionalnih, jednogodišnjih i obnovljivih biljnih vrsta kao što su konoplja i lan. Lignin i pektin su veoma važne necelulozne primjese koje se pojavljuju u vlaknima konoplje. Da bi se utvrdila efikasnost njihovog uklanjanja iz vlakana konoplje provedene su četiri vrste hemijskih obrada ključalim rastvorom natrijum hidroksida; ključalim rastvorom natrijum hidroksida a zatim vodonik peroksidom; ključalim rastvorom natrijum hidroksida a zatim kalijumpermanganatom; i vodonik peroksidom. Određen je sadržaj lignina u vlaknima prije i poslije obrade. Rezultati pokazuju da obrada ključalim rastvorom natrijum hidroksida dosta uspješno uklanja lignin a dodatna obrada peroksidom samo poboljšava njegovo uklanjanje i bijeli vlakna. Pokazano je, da je tako dobijena celuloza visoko kvalitetan materijal, koji se može uspješno koristiti za dobijanje hemijskih celuloznih vlakana, direktnim rastvaranjem u N-metilmorfolin N-oksidu (NMMO), što će predstavljati dominantnu tehnologiju proizvodnje ovih vlakana u 21-om vijeku.
PB  - Univerzitet u Nišu - Tehnološki fakultet, Leskovac
T2  - Zbornik radova Tehnološkog fakulteta, Leskovac
T1  - Obtaining of high quality cellulose from the hemp fibers
T1  - Dobijanje visoko kvalitetne celuloze iz vlakana konoplje
EP  - 394
IS  - 14
SP  - 386
UR  - https://hdl.handle.net/21.15107/rcub_technorep_802
ER  - 

@article{
author = "Janjić, Svjetlana and Škundrić, Petar and Kostić, Mirjana and Lazić, Biljana D.",
year = "2005",
abstract = "In recent years growing attention has been paid to production of cellulose from unconventional, annually and renewable plants such as hemp and flax. Lignin and pectin are very important noncellulosic substances occurring in hemp fibers. In order to establish effects on lignin removal, four types chemical processes are conducted: with boiling sodium hydroxide, with boiling sodium hydroxide and afterwards with permanganate; with boiling sodium hydroxide and afterwards with hydrogen peroxide; and with hydrogen peroxide. Lignin in hemp before and after chemical processing is characterized. The results indicate that the alkaline boiling process is effective for removing lignin and afterwards treatment with peroxide additionally removing lignin and also increase fiber whiteness. It is establish that, the cellulose obtained from hemp fibres by previous treatment is high quality materials for the process of manufacturing cellulose fibers based on direct cellulose dissolution in the N-methylmorpholine N-oxide (NMMO) as predominating technology for the 21st century., Poslednjih godina je posvećena velika pažnja dobijanju celuloze od nekonvencionalnih, jednogodišnjih i obnovljivih biljnih vrsta kao što su konoplja i lan. Lignin i pektin su veoma važne necelulozne primjese koje se pojavljuju u vlaknima konoplje. Da bi se utvrdila efikasnost njihovog uklanjanja iz vlakana konoplje provedene su četiri vrste hemijskih obrada ključalim rastvorom natrijum hidroksida; ključalim rastvorom natrijum hidroksida a zatim vodonik peroksidom; ključalim rastvorom natrijum hidroksida a zatim kalijumpermanganatom; i vodonik peroksidom. Određen je sadržaj lignina u vlaknima prije i poslije obrade. Rezultati pokazuju da obrada ključalim rastvorom natrijum hidroksida dosta uspješno uklanja lignin a dodatna obrada peroksidom samo poboljšava njegovo uklanjanje i bijeli vlakna. Pokazano je, da je tako dobijena celuloza visoko kvalitetan materijal, koji se može uspješno koristiti za dobijanje hemijskih celuloznih vlakana, direktnim rastvaranjem u N-metilmorfolin N-oksidu (NMMO), što će predstavljati dominantnu tehnologiju proizvodnje ovih vlakana u 21-om vijeku.",
publisher = "Univerzitet u Nišu - Tehnološki fakultet, Leskovac",
journal = "Zbornik radova Tehnološkog fakulteta, Leskovac",
title = "Obtaining of high quality cellulose from the hemp fibers, Dobijanje visoko kvalitetne celuloze iz vlakana konoplje",
pages = "394-386",
number = "14",
url = "https://hdl.handle.net/21.15107/rcub_technorep_802"
}

Janjić, S., Škundrić, P., Kostić, M.,& Lazić, B. D.. (2005). Obtaining of high quality cellulose from the hemp fibers. in Zbornik radova Tehnološkog fakulteta, Leskovac
Univerzitet u Nišu - Tehnološki fakultet, Leskovac.(14), 386-394.
https://hdl.handle.net/21.15107/rcub_technorep_802

Janjić S, Škundrić P, Kostić M, Lazić BD. Obtaining of high quality cellulose from the hemp fibers. in Zbornik radova Tehnološkog fakulteta, Leskovac. 2005;(14):386-394.
https://hdl.handle.net/21.15107/rcub_technorep_802 .

Janjić, Svjetlana, Škundrić, Petar, Kostić, Mirjana, Lazić, Biljana D., "Obtaining of high quality cellulose from the hemp fibers" in Zbornik radova Tehnološkog fakulteta, Leskovac, no. 14 (2005):386-394,
https://hdl.handle.net/21.15107/rcub_technorep_802 .