TY  - CONF
AU  - Obradović, Vera
AU  - Bajić, Danica
AU  - Sejkot, Petr
AU  - Fidanovski, Bojana
AU  - Machalická, Klára V.
AU  - Vokáč, Miroslav
PY  - 2021
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/7076
AB  - The para-aramid fibres (Kevlar, Twaron, Kolon) are high performance polymeric fibres characterized by their high tenacity, strength to weight ratio and impact resistance. They are used for the soft body armour structures in ballistics and for the manufacture of parts in aerospace and automotive industry.
In this study, the specimens were made from the two-layered Kolon fabrics impregnated with epoxy resin where some silicon carbide (SiC) microparticles or SiC nanofibres were added as reinforcement. These composite specimens
were fabricated by hot compression and curing of epoxy resin.
Despite their good mechanical strength it is a well-known fact that the mechanical properties of epoxy resins are affected by moisture absorption. The tensile and impact properties of the untreated specimens were compared with the ones that underwent water absorption in the duration of 72h (immersion or humidity) followed by desorption. The immersion of the specimens in water and the exposure to high humidity (70%) were completed in accordance with the ISO 62 standard while the tensile test was performed according to the ASTM D 3039 standard. Furthermore, the tensile test simulation of the Kolon/epoxy composite by using software Abaqus® was accomplished.
For the determination of the absorbed impact energy and the impact toughness of the composite specimens, an impact test was performed by using the Charpy impact pendulum in accordance with the ASTM D5942 standard.
PB  - Royal Society of Chemistry
C3  - Book of poster Abstracts / 15th International conference on materials chemistry (MC15) - online, United Kingdom, July 12-15, 2021
T1  - Effect of moisture absorption on the mechanical properties of Kolon/ epoxy composites
SP  - P104
UR  - https://hdl.handle.net/21.15107/rcub_technorep_7076
ER  - 

@conference{
author = "Obradović, Vera and Bajić, Danica and Sejkot, Petr and Fidanovski, Bojana and Machalická, Klára V. and Vokáč, Miroslav",
year = "2021",
abstract = "The para-aramid fibres (Kevlar, Twaron, Kolon) are high performance polymeric fibres characterized by their high tenacity, strength to weight ratio and impact resistance. They are used for the soft body armour structures in ballistics and for the manufacture of parts in aerospace and automotive industry.
In this study, the specimens were made from the two-layered Kolon fabrics impregnated with epoxy resin where some silicon carbide (SiC) microparticles or SiC nanofibres were added as reinforcement. These composite specimens
were fabricated by hot compression and curing of epoxy resin.
Despite their good mechanical strength it is a well-known fact that the mechanical properties of epoxy resins are affected by moisture absorption. The tensile and impact properties of the untreated specimens were compared with the ones that underwent water absorption in the duration of 72h (immersion or humidity) followed by desorption. The immersion of the specimens in water and the exposure to high humidity (70%) were completed in accordance with the ISO 62 standard while the tensile test was performed according to the ASTM D 3039 standard. Furthermore, the tensile test simulation of the Kolon/epoxy composite by using software Abaqus® was accomplished.
For the determination of the absorbed impact energy and the impact toughness of the composite specimens, an impact test was performed by using the Charpy impact pendulum in accordance with the ASTM D5942 standard.",
publisher = "Royal Society of Chemistry",
journal = "Book of poster Abstracts / 15th International conference on materials chemistry (MC15) - online, United Kingdom, July 12-15, 2021",
title = "Effect of moisture absorption on the mechanical properties of Kolon/ epoxy composites",
pages = "P104",
url = "https://hdl.handle.net/21.15107/rcub_technorep_7076"
}

Obradović, V., Bajić, D., Sejkot, P., Fidanovski, B., Machalická, K. V.,& Vokáč, M.. (2021). Effect of moisture absorption on the mechanical properties of Kolon/ epoxy composites. in Book of poster Abstracts / 15th International conference on materials chemistry (MC15) - online, United Kingdom, July 12-15, 2021
Royal Society of Chemistry., P104.
https://hdl.handle.net/21.15107/rcub_technorep_7076

Obradović V, Bajić D, Sejkot P, Fidanovski B, Machalická KV, Vokáč M. Effect of moisture absorption on the mechanical properties of Kolon/ epoxy composites. in Book of poster Abstracts / 15th International conference on materials chemistry (MC15) - online, United Kingdom, July 12-15, 2021. 2021;:P104.
https://hdl.handle.net/21.15107/rcub_technorep_7076 .

Obradović, Vera, Bajić, Danica, Sejkot, Petr, Fidanovski, Bojana, Machalická, Klára V., Vokáč, Miroslav, "Effect of moisture absorption on the mechanical properties of Kolon/ epoxy composites" in Book of poster Abstracts / 15th International conference on materials chemistry (MC15) - online, United Kingdom, July 12-15, 2021 (2021):P104,
https://hdl.handle.net/21.15107/rcub_technorep_7076 .

TY  - CONF
AU  - Bajić, Danica M.
AU  - Fidanovski, Bojana
AU  - Radisavljević, Igor
AU  - Bogosavljević, Marica
AU  - Totovski, Ljubica
AU  - Stojanović, Dušica B.
PY  - 2021
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/6933
AB  - As one of transition metal dichalogenides, tungsten disulphide (WS2) is well known for its solid
lubricating behavior, but besides this feature, it exhibits extraordinary thermal stability and mechanical
resistance. The outstanding mechanical strength of WS2 is most pronounced when it comes in form of
multi-layer hollow nanoparticles and nanotubes: inorganic fullerene-like nanoparticles and inorganic
nanotubes, denoted as IF-WS2 and INT-WS2, respectively. These structures have extraordinary shock resistance
properties, pressure and heat resistance, that can be exploited for a variety of applications. They have been
studied as reinforcing fillers of various polymers, but they might be also added as reinforcement of matrix in
more complex composites, like CFRPs. Our research aimed to examine their reinforcing effect on laminated
composites based on aramid fabric and poly(vinyl butyral), PVB, intended for demanding applications: in
personal protection equipment, ballistic protection, sports equipment, automotive, nautical and aircraft
engineering. WS2 nanostructures have been incorporated in PVB by temporary dissolving in ethanol, by
ultrasonication and intensive mechanical mixing. After impregnation of aramid fabrics ethanol would
evaporate, and layers of aramid with thermoplastic binder PVB would be integrated by hot pressing. SEM
analysis confirms the uniform distribution of WS2 nanostructures in the prepared composite material. DSC
analysis reveals the effect of WS2 addition on thermal resistance of the new material, while PVB/aramid
mechanical resistance was examined using DMA, impact test and tensile test. IF- WS2 has imported higher
thermal resistance and ductility improvement, while INT-WS2 has significantly improved tensile and impact
strength of the composite.
C3  - Abstract Book / 3 rd Edition of Materials Science and Nanoscience Webinar, V-Mat2021, September 17-18, 2021
T1  - WS2 nanostructures as thermo-mechanical reinforcement of composite materials for advanced applications
SP  - 40
UR  - https://hdl.handle.net/21.15107/rcub_technorep_6933
ER  - 

@conference{
author = "Bajić, Danica M. and Fidanovski, Bojana and Radisavljević, Igor and Bogosavljević, Marica and Totovski, Ljubica and Stojanović, Dušica B.",
year = "2021",
abstract = "As one of transition metal dichalogenides, tungsten disulphide (WS2) is well known for its solid
lubricating behavior, but besides this feature, it exhibits extraordinary thermal stability and mechanical
resistance. The outstanding mechanical strength of WS2 is most pronounced when it comes in form of
multi-layer hollow nanoparticles and nanotubes: inorganic fullerene-like nanoparticles and inorganic
nanotubes, denoted as IF-WS2 and INT-WS2, respectively. These structures have extraordinary shock resistance
properties, pressure and heat resistance, that can be exploited for a variety of applications. They have been
studied as reinforcing fillers of various polymers, but they might be also added as reinforcement of matrix in
more complex composites, like CFRPs. Our research aimed to examine their reinforcing effect on laminated
composites based on aramid fabric and poly(vinyl butyral), PVB, intended for demanding applications: in
personal protection equipment, ballistic protection, sports equipment, automotive, nautical and aircraft
engineering. WS2 nanostructures have been incorporated in PVB by temporary dissolving in ethanol, by
ultrasonication and intensive mechanical mixing. After impregnation of aramid fabrics ethanol would
evaporate, and layers of aramid with thermoplastic binder PVB would be integrated by hot pressing. SEM
analysis confirms the uniform distribution of WS2 nanostructures in the prepared composite material. DSC
analysis reveals the effect of WS2 addition on thermal resistance of the new material, while PVB/aramid
mechanical resistance was examined using DMA, impact test and tensile test. IF- WS2 has imported higher
thermal resistance and ductility improvement, while INT-WS2 has significantly improved tensile and impact
strength of the composite.",
journal = "Abstract Book / 3 rd Edition of Materials Science and Nanoscience Webinar, V-Mat2021, September 17-18, 2021",
title = "WS2 nanostructures as thermo-mechanical reinforcement of composite materials for advanced applications",
pages = "40",
url = "https://hdl.handle.net/21.15107/rcub_technorep_6933"
}

Bajić, D. M., Fidanovski, B., Radisavljević, I., Bogosavljević, M., Totovski, L.,& Stojanović, D. B.. (2021). WS2 nanostructures as thermo-mechanical reinforcement of composite materials for advanced applications. in Abstract Book / 3 rd Edition of Materials Science and Nanoscience Webinar, V-Mat2021, September 17-18, 2021, 40.
https://hdl.handle.net/21.15107/rcub_technorep_6933

Bajić DM, Fidanovski B, Radisavljević I, Bogosavljević M, Totovski L, Stojanović DB. WS2 nanostructures as thermo-mechanical reinforcement of composite materials for advanced applications. in Abstract Book / 3 rd Edition of Materials Science and Nanoscience Webinar, V-Mat2021, September 17-18, 2021. 2021;:40.
https://hdl.handle.net/21.15107/rcub_technorep_6933 .

Bajić, Danica M., Fidanovski, Bojana, Radisavljević, Igor, Bogosavljević, Marica, Totovski, Ljubica, Stojanović, Dušica B., "WS2 nanostructures as thermo-mechanical reinforcement of composite materials for advanced applications" in Abstract Book / 3 rd Edition of Materials Science and Nanoscience Webinar, V-Mat2021, September 17-18, 2021 (2021):40,
https://hdl.handle.net/21.15107/rcub_technorep_6933 .