Renata Dobrzyńska

Dr. Renata Dobrzyńska

Faculty of Maritime Technology and Transport, West Pomeranian University of Technology, Szczecin, Zachodniopomorskie, Poland
orcid

Research Focus & Metrics

Academic Career Length

18Years (2009-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
1 October 2020 in Composites Part B: Engineering
Verified
Journal Article
Open access
YWYanliang Wen
Yanliang Wen
XLXiaoguang Liu
Xiaoguang Liu
XWXin Wen
Xin Wen
XCXuecheng Chen
Xuecheng Chen
KSKarolina Szymańska
Karolina Szymańska
EMEwa Mijowska
Ewa Mijowska

30 July 2013 in Journal of Thermal Analysis and Calorimetry
Verified
Journal Article
Open access
PDF file
Przemysław RybińskiPrzemysław Rybiński
Przemysław Rybiński
GJGrażyna Janowska
Grażyna Janowska
RDRenata Dobrzyńska
Renata Dobrzyńska
AKAgnieszka Kucharska
Agnieszka Kucharska
This paper presents the results of investigating the thermal stability, flammability, and fire hazard of cross-linked EVM/NBR blends unfilled and filled with halogenless flame-retardant compounds such as melamine cyanurate or magnesium hydroxide. The thermal analysis of the blends was carried out in the atmosphere of air. The activation energy of the composite destruction was determined by two non-isothermal methods: Flynn–Wall–Ozawa’s and Kissinger’s methods. The flammability of the composites obtained was determined by the method of oxygen index and on the basis of their combustion in air. The fire hazard of the vulcanizates investigated was determined with the use of a cone calorimeter and on the basis of toxicometric parameters W LC50SM. The test results have shown that the flame retardants used increase the thermal stability of the cross-linked blends and decrease their flammability, and thereby allow one to obtain self-extinguishing or non-flammable polymeric materials. The cross-linked EVM/NBR blends filled with these flame-retardant compounds are characterized by good mechanical properties and reduced fire hazard.

29 June 2021 in Polymers
Verified
Journal Article
Open access
PDF file
Sandra PaszkiewiczSandra Paszkiewicz
Sandra Paszkiewicz
IIIzabela Irska
Izabela Irska
Iman TaraghiIman Taraghi
Iman Taraghi
EPElżbieta Piesowicz
Elżbieta Piesowicz
JSJakub Sieminski
Jakub Sieminski
BSBartłomiej Szymczak
Bartłomiej Szymczak
The effect of the presence of halloysite nanotubes (HNTs) and silane-treated alumina trihydrate (ATH-sil) nanofillers on the mechanical, thermal, and flame retardancy properties of ethylene-vinyl acetate (EVA) copolymer/low-density polyethylene (LDPE) blends was investigated. Different weight percentages of HNT and ATH-sil nanoparticles, as well as the hybrid system of those nanofillers, were melt mixed with the polymer blend (reference sample) using a twin-screw extruder. The morphology of the nanoparticles and polymer compositions was studied using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The mechanical properties, hardness, water absorption, and melt flow index (MFI) of the compositions were assessed. The tensile strength increases as a function of the amount of HNT nanofiller; however, the elongation at break decreases. In the case of the hybrid system of nanofillers, the compositions showed superior mechanical properties. The thermal properties of the reference sample and those of the corresponding sample with nanofiller blends were studied using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Two peaks were observed in the melting and crystallization temperatures. This shows that the EVA/LDPE is an immiscible polymer blend. The thermal stability of the blends was improved by the presence of HNTs and ATH-sil nanoparticles. Thermal degradation temperatures were shifted to higher values by the presence of hybrid nanofillers. Finally, the flammability of the compositions was assessed. Flammability as reflected by the limiting oxygen index (OI) was increased by the presence of HNT and ATH-sil nanofiller and a hybrid system of the nanoparticles.

9 May 2023 in Applied Sciences
Verified
Journal Article
Open access
PDF file
KBKatarzyna Bryll
Katarzyna Bryll
EKEwelina Kostecka
Ewelina Kostecka
MSMieczysław Scheibe
Mieczysław Scheibe
RDRenata Dobrzyńska
Renata Dobrzyńska
TKTomasz Kostecki
Tomasz Kostecki
IKIga Korczyńska
Iga Korczyńska
In small vessels, for example, yachts, polymer–glass composites are mainly used for their construction. However, the disposal and/or recycling of composite units is very difficult. It is advisable to solve the problem of disposing of post-consumer items as soon as possible. Therefore, alternative, environmentally friendly, but also durable and safe construction materials are being sought. Such materials can be polymer–natural composites, which can be used as a potential material (alternative to polymer–glass composites) for the construction of small vessels. However, its performance properties should be investigated as new construction materials. The possibility of using polymer–hemp composites was assessed in terms of safety, i.e., the fire resistance of these materials. This paper compares selected characteristics that the reaction of composite materials has to fire with glass fiber and hemp fiber reinforcements. During the study, a natural composite reinforced with hemp fabric was investigated. Based on the laboratory test, it was found that this composite showed better susceptibility to energy recycling, with a relatively small deterioration in fire resistance compared to the composite reinforced with glass fiber. This material could therefore be a potential construction material for small vessels if we consider fire resistance in terms of the safety of the vessel’s operation.

1 January 2009 in Polish Maritime Research
Verified
Journal Article
Open access
PDF file
RDRenata Dobrzyńska
Renata Dobrzyńska
Upholstery furniture and bedding components which presently are required to satisfy conditions of resistance to only small fire setting sources, really constitute a serious source of toxic hazard. The proposed method of toxic hazard assessment in the initial phase of fire progress, due to thermal decomposition and combustion of materials, makes appropriate selection of outfitting materials for shipboard living and service accommodations already in ship design phase, possible. Practical application of the proposed algorithm of selection procedure of suitable outfitting and decorative materials intended for shipboard living accommodations would decrease fire toxic hazard level in such accommodations.

22 January 2025 in Polymers
Verified
Journal Article
Open access
PDF file
MSMieczysław Scheibe
Mieczysław Scheibe
RDRenata Dobrzyńska
Renata Dobrzyńska
MUMagdalena Urbaniak
Magdalena Urbaniak
Andrzej K. BłędzkiAndrzej K. Błędzki
Andrzej K. Błędzki
This paper presents the potential for an alternative use of structural polymer composite reinforcement, made from natural industrial hemp (Cannabis sativa L.) fibres, in the manufacture of selected products in the shipbuilding industry. This research used fabrics made from unmodified and chemically modified industrial hemp fibres. The primary research focus was on determining the impact strength of the new eco-friendly structural composites produced after long-term storage in representative aqueous environments. Also presented are the results of fire response tests of these composites in the context of their disposal by energy recycling. The tests carried out also referred to a well-defined glass fibre-reinforced polymer composite, from which a control slab of the actual product was realistically produced in the form of a representative section of a 34-foot boat hull plate below the waterline. The results of this basic research into these structural composites confirmed the validity of continuing, respectively, application and implementation research, aimed at producing composites dedicated to selected products of the shipbuilding industry.