TY  - JOUR
AU  - Kekez, Branka
AU  - Gojgić-Cvijović, Gordana
AU  - Jakovljević, Dragica
AU  - Pavlović, Vladimir
AU  - Beskoski, Vladimir
AU  - Popović, Aleksandar
AU  - Vrvić, Miroslav M.
AU  - Nikolić, Vladimir
PY  - 2016
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/4034
AB  - Novel macromolecular graft copolymers were synthesized by reaction of the hydroxyl groups of the microbial polysaccharide levan, produced using Bacillus licheniformis, with polystyrene (Lev-g-PS). Synthesis was performed by the free radical reaction using potassium persulfate (PPS) as initiator. The prepared copolymer was characterized by FTIR, SEM, TG/DTA, XRD and C-13 NMR. The influence of the different conditions (reaction temperature, air or nitrogen atmosphere, reaction time, type of amines and ascorbic acid (AA) concentration) on the grafting reaction was investigated. Results showed that maximum percentage of grafting (58.1%) was achieved at a reaction temperature 70 degrees C, in a nitrogen atmosphere and using dimethylethanolamine (DMEA) as the amine activator. On the basis of the obtained results, the likely reaction mechanism was proposed. Synthesized copolymers have better thermal stability in comparison with their initial components. Copolymers such as Lev-g-PS could potentially have many applications, such as compatibilizers and material for membranes.
PB  - Elsevier Sci Ltd, Oxford
T2  - Carbohydrate Polymers
T1  - Synthesis and characterization of a new type of levan-graft-polystyrene copolymer
EP  - 29
SP  - 20
VL  - 154
DO  - 10.1016/j.carbpol.2016.08.001
ER  - 

@article{
author = "Kekez, Branka and Gojgić-Cvijović, Gordana and Jakovljević, Dragica and Pavlović, Vladimir and Beskoski, Vladimir and Popović, Aleksandar and Vrvić, Miroslav M. and Nikolić, Vladimir",
year = "2016",
abstract = "Novel macromolecular graft copolymers were synthesized by reaction of the hydroxyl groups of the microbial polysaccharide levan, produced using Bacillus licheniformis, with polystyrene (Lev-g-PS). Synthesis was performed by the free radical reaction using potassium persulfate (PPS) as initiator. The prepared copolymer was characterized by FTIR, SEM, TG/DTA, XRD and C-13 NMR. The influence of the different conditions (reaction temperature, air or nitrogen atmosphere, reaction time, type of amines and ascorbic acid (AA) concentration) on the grafting reaction was investigated. Results showed that maximum percentage of grafting (58.1%) was achieved at a reaction temperature 70 degrees C, in a nitrogen atmosphere and using dimethylethanolamine (DMEA) as the amine activator. On the basis of the obtained results, the likely reaction mechanism was proposed. Synthesized copolymers have better thermal stability in comparison with their initial components. Copolymers such as Lev-g-PS could potentially have many applications, such as compatibilizers and material for membranes.",
publisher = "Elsevier Sci Ltd, Oxford",
journal = "Carbohydrate Polymers",
title = "Synthesis and characterization of a new type of levan-graft-polystyrene copolymer",
pages = "29-20",
volume = "154",
doi = "10.1016/j.carbpol.2016.08.001"
}

Kekez, B., Gojgić-Cvijović, G., Jakovljević, D., Pavlović, V., Beskoski, V., Popović, A., Vrvić, M. M.,& Nikolić, V.. (2016). Synthesis and characterization of a new type of levan-graft-polystyrene copolymer. in Carbohydrate Polymers
Elsevier Sci Ltd, Oxford., 154, 20-29.
https://doi.org/10.1016/j.carbpol.2016.08.001

Kekez B, Gojgić-Cvijović G, Jakovljević D, Pavlović V, Beskoski V, Popović A, Vrvić MM, Nikolić V. Synthesis and characterization of a new type of levan-graft-polystyrene copolymer. in Carbohydrate Polymers. 2016;154:20-29.
doi:10.1016/j.carbpol.2016.08.001 .

Kekez, Branka, Gojgić-Cvijović, Gordana, Jakovljević, Dragica, Pavlović, Vladimir, Beskoski, Vladimir, Popović, Aleksandar, Vrvić, Miroslav M., Nikolić, Vladimir, "Synthesis and characterization of a new type of levan-graft-polystyrene copolymer" in Carbohydrate Polymers, 154 (2016):20-29,
https://doi.org/10.1016/j.carbpol.2016.08.001 . .