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Politechniki Gdańskiej

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  • The Development of Toxoplasma gondii Recombinant Trivalent Chimeric Proteins as an Alternative to Toxoplasma Lysate Antigen (TLA) in Enzyme-Linked Immunosorbent Assay (ELISA) for the Detection of Immunoglobulin G (IgG) in Small Ruminants
    • Bartłomiej Tomasz Ferra
    • Maciej Chyb
    • Karolina Sołowińska
    • Lucyna Holec-Gąsior
    • Marta Skwarecka
    • Karolina Baranowicz
    • Justyna Gatkowska
    2024 INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES

    This study presents an evaluation of seventeen newly produced recombinant trivalent chimeric proteins (containing the same immunodominant fragment of SAG1 and SAG2 of Toxoplasma gondii antigens, and an additional immunodominant fragment of one of the parasite antigens, such as AMA1, GRA1, GRA2, GRA5, GRA6, GRA7, GRA9, LDH2, MAG1, MIC1, MIC3, P35, and ROP1) as a potential alternative to the whole-cell tachyzoite lysate (TLA) used in the detection of infection in small ruminants. These recombinant proteins, obtained by genetic engineering and molecular biology methods, were tested for their reactivity with specific anti-Toxoplasma IgG antibodies contained in serum samples of small ruminants (192 samples of sheep serum and 95 samples of goat serum) using an enzyme-linked immunosorbent assay (ELISA). The reactivity of six recombinant trivalent chimeric proteins (SAG1-SAG2-GRA5, SAG1-SAG2-GRA9, SAG1-SAG2-MIC1, SAG1-SAG2-MIC3, SAG1-SAG2-P35, and SAG1-SAG2-ROP1) with IgG antibodies generated during T. gondii invasion was comparable to the sensitivity of TLA-based IgG ELISA (100%). The obtained results show a strong correlation with the results obtained for TLA. This suggests that these protein preparations may be a potential alternative to TLA used in commercial tests and could be used to develop a cheaper test for the detection of parasite infection in small ruminants.

  • The effect of 1,4-butanediol on the efficiency of CO2 absorption and inhibition of NH3 escape during the mineral carbonation of gypsum
    • Temesgen Amibo
    • Donata Konopacka-Łyskawa
    2024 Pełny tekst

    This study explored the optimal concentration of 1,4-butanediol for maximizing CO2 absorption and minimizing ammonia desorption. Mineral carbonation of gypsum slurry was carried out in a bubble reactor with a magnetic stirrer maintaining constant speed for 1 hour. The gas introduced to the reactor was a mixture of CO2 and air. The gas flow was controlled by the mass controllers. Gas sensors were used to determine the concentration of CO2 and NH3 in the outlet gas. The initial and final pH values were measured. The liquid phase was ammonia solutions at a concentration of 1.69 mol.dm-3 with the addition of varying concentrations of 1,4-butanediol (ranging from 0.1 to 0.5 mol. dm-3). The ratio of gypsum to liquid phase was maintained as 1:14 (kg. dm-3). Based on measured CO2 and NH3 concentrations, the efficiency of carbon dioxide absorption and the efficiency of ammonia escape inhibition were calculated.

  • The effect of aeration mode (intermittent vs. continuous) on nutrient removal and greenhouse gas emissions in the wastewater treatment plant of Corleone (Italy)
    • Giorgio Mannina
    • Paulo Marcelo Bosco Mofatto
    • Alida Cosenza
    • Daniele Trapani Di
    • Hazal Gulhan
    • Antonio Mineo
    • Jacek Mąkinia
    2024 Pełny tekst SCIENCE OF THE TOTAL ENVIRONMENT

    The paper reports the results of an experimental study aimed at comparing two configurations of a full-scale wastewater treatment plant (WWTP): conventional activated sludge (CAS) and oxic-settling-anaerobic process (OSA) with intermittent aeration (IA). A comprehensive monitoring campaign was carried out to assess multiple parameters for comparing the two configurations: carbon and nutrient removal, greenhouse gas emissions, respirometric analysis, and sludge production. A holistic approach has been adopted in the study with the novelty of including the carbon footprint (CF) contribution (as direct, indirect and derivative emissions) in comparing the two configurations. Results showed that the OSA-IA configuration performed better in total chemical oxygen demand (TCOD) and ortho-phosphate (PO4-P) removal. CAS performed better for Total Suspended Solids (TSS) removal showing a worsening of settling properties for OSA-IA. The heterotrophic yield coefficient and maximum growth rate decreased, suggesting a shift to sludge reduction metabolism in the OSA-IA configuration. Autotrophic biomass showed a reduced yield coefficient and maximum growth yield due to the negative effects of the sludge holding tank in the OSA-IA configuration on nitrification. The OSA-IA configuration had higher indirect emissions (30.5 % vs 21.3 % in CAS) from additional energy consumption due to additional mixers and sludge recirculation pumps. The CF value was lower for OSA-IA than for CAS configuration (0.36 kgCO2/m3 vs 0.39 kgCO2/m3 in CAS).

  • The effect of elevated temperature on LCF damage growth in 2024AA – Experiment and modeling
    • Anna Falkowska
    • Adam Tomczyk
    • Andrzej Seweryn
    2024 ENGINEERING FAILURE ANALYSIS

    This paper presents the results of experimental low-cycle fatigue (LCF) tests conducted on EN-AW 2024 alloy in T3511 temper at 100 ◦C, 200 ◦C and 300 ◦C. The material’s basic fatigue characteristics were determined, such as fatigue life curve and cyclic strain curve. Both the hysteresis loop and nature of fracture surfaces obtained in macro- and microscopic observations (scanning electron microscope, SEM) were accounted for. The results of tests at elevated temperature were compared with results obtained at room temperature in the authors’ previous papers. Based on the results of experimental tests, an analytical model of fatigue damage growth was proposed. In this model, it was assumed that damage accumulation mainly depends on the current normal stress and increment of plastic strain. Dependencies of the model’s parameters with respect to temperature were determined, and the model was validated experimentally. Good concurrency of the numerical simulations with the experimental results was obtained.

  • The effect of environmental turbulence on cyber security risk management and organizational resilience
    • Susanne Durst
    • Christoph Hinteregger
    • Małgorzata Zięba
    2024 Pełny tekst COMPUTERS & SECURITY

    Even though there is a plethora of research on the role of environmental turbulence in organizational performance in general, little attention has been paid to the effect of environmental turbulence on cyber security risk management and further - organizational resilience. Drawing on the resource-based view and contingency theory, this study investigates how technological and market turbulence influence organizational cyber security risk management (CSRM) and then organizational resilience. Using a data set from 150 European companies, the study findings show how the two types of turbulence have different effects on CSRM in the companies studied. Technological turbulence directly impacts the firms’ cyber security risk maturity while market turbulence has a direct positive affect on firms’ cyber security risk perception. The study also determines the interplay between risk perception and risk maturity and subsequent resilience.

  • The effect of groyne field on trapping macroplastic. Preliminary results from laboratory experiments
    • Łukasz Przyborowski
    • Zuzanna Cuban
    • Anna Łoboda
    • Małgorzata Robakiewicz
    • Stanisław Biegowski
    • Tomasz Kolerski
    2024 SCIENCE OF THE TOTAL ENVIRONMENT

    Macroplastic, a precursor of microplastic pollution, has become a new scope of research interest. However, the physical processes of macroplastic transport and deposition in rivers are poorly understood, which makes the decisions of where to locate macroplastic trapping infrastructure difficult. In this research, we conducted a series of experiments in a laboratory channel, exploring the impact of groynes and flexible artificial vegetation on the floating macroplastic litter. The goal was to investigate the litter paths with different obstruction arrangements, which was done by implementing a particle tracking technique on video recordings from each experimental run. We found that increasing discharge correlated with the number of plastic litter floating into the recirculation zone within the groyne fields, especially if the upstream groyne had an extended length. This produced a strong mixing interface between the main flow and the groyne field, while a vegetation patch added in the same groyne field changed the paths of plastic litter by deflecting the flow. We noticed that during a moderate discharge rate, the litter pieces flowing into the groyne field with the vegetation circulated there for the longest period, and some of them got entangled between floating stems when discharge was at its lowest. This phenomenon points to the conclusion that low flow velocity paired with the presence of vegetation can be a primer for plastic deposition and consequently, its degradation. The insights from the experiment allowed us to recommend a place downstream of an extended groyne as the desirable (efficient) area for installing a plastic trapping infrastructure or conducting plastic cleaning actions.

  • The Effect of Hyperbaric Storage on the Nutritional Value and Retention of Certain Bioactive Proteins in Human Milk
    • Katarzyna Mazur
    • Barbara Kusznierewicz
    • Dorota Martysiak-Żurowska
    • Izabela Drążkowska
    • Edyta Malinowska-Pańczyk
    2024 Pełny tekst Nutrients

    Human milk (HM) contains the essential macronutrients and bioactive compounds necessary for the normal growth and development of newborns. The milk collected by human milk banks is stored frozen and pasteurized, reducing its nutritional and biological value. The purpose of this study was to determine the effect of hyperbaric storage at subzero temperatures (HS-ST) on the macronutrients and bioactive proteins in HM. As control samples, HM was stored at the same temperatures under 0.1 MPa. A Miris HM analyzer was used to determine the macronutrients and the energy value. The lactoferrin (LF), lysozyme (LYZ) and α-lactalbumin (α-LAC) content was checked using high-performance liquid chromatography, and an ELISA test was used to quantify secretory immunoglobulin A (sIgA). The results showed that the macronutrient content did not change significantly after 90 days of storage at 60 MPa/−5 °C, 78 MPa/−7 °C, 111 MPa/−10 °C or 130 MPa/−12 °C. Retention higher than 90% of LYZ, α-LAC, LF and sIgA was observed in the HM stored at conditions of up to 111 MPa/−10 °C. However, at 130 MPa/−12 °C, there was a reduction in LYZ and LF, by 39 and 89%, respectively. The storage of HM at subzero temperatures at 0.1 MPa did not affect the content of carbohydrates or crude and true protein. For fat and the energy value, significant decreases were observed at −5 °C after 90 days of storage.

  • The effect of preliminary creep-strain on material behavior under LCF tension/compression and pure torsion regimes
    • Adam Tomczyk
    • Wojciech Grodzki
    • Andrzej Seweryn
    2024 INTERNATIONAL JOURNAL OF FATIGUE

    This paper presents the results of experimental tests of monotonic tension and torsion, creep-rupture and preliminary creep at 200C and 300C, as well as low-cycle fatigue of 2024 T3511 aluminum alloy. The fatigue process was conducted at room temperature for uniaxial tension/compression and torsion. The as-received material and pre-deformed material were also investigated during creep at elevated temperature. Basic monotonic, creep and fatigue characteristics of the material were determined. Detailed micro- and macroscopic analyses of fracture surfaces (scanning electron microscopy, SEM) were carried out. The influence of different creep pre-deformation histories at elevated temperature on the behavior of the studied alloy were characterized with respect to monotonic and cyclic loads at room temperature.

  • The Effect of Steaming Beech, Birch and Maple Woods on Qualitative Indicators of the Surface
    • Michal Dudiak
    • Richard Kminiak
    • Adrian Banski,
    • Daniel Chuchała
    2024 Pełny tekst Coatings

    This work presents the effect of steaming beech, birch and maple woods on the resulting quality of the milled wood surface. The steaming process of the studied woods results in a targeted change in the color of the wood, which changes from the original light white-gray color to fine reddishbrown to dark brown color shades that are more or less saturated depending on the temperature of the saturated water steam. The color changes achieved during the modification process were identified using coordinates in the CIE L*a*b* color space. The achieved color changes were described through the total color difference of ΔE* and defined through classification grades using a color scale. The technological process of wood steaming with saturated water steam for the purpose of a targeted change in the color of the wood and experimental measurements of the roughness of the milled wood surface proved that the wood steaming process has a positive effect on the roughness of the wood surface of the investigated trees, depending on the steaming temperature. The reduction of roughness in the process of the modification of beech wood compared with native wood was at the temperature of the saturated water steam as follows: tI = 105 ± 2.5 ◦C by Ra = 12.3%, at tII = 125 ± 2.5 ◦C by Ra = 15.4%, at tIII = 135 ± 2.5 ◦C by Ra = 16.9%. By modifying birch wood at tIII = 135 ± 2.5 ◦C, the roughness decreased by Ra = 13.4%; the surface roughness decreased by Ra = 15.8% compared with native wood by modifying maple wood. The roughness of the milled surface of modified wood in individual treatment modes decreased compared with native wood, which means that the milled surface of modified wood is of a better quality, which is positive for its practical use.

  • The effect of using jug-type water filters on selected metals concentration in tap water – a case study
    • Hubert Kwiatkowski
    • Ksawery Kreft
    • Oskar Ronda
    • Bartłomiej Cieślik
    2024 JOURNAL OF WATER AND HEALTH

    In this study, the effect of the filtration process on Na, K, Mg, Ca, Fe and Zn concentration in water, using filters from one of the leading European manufacturers, was investigated. The increase in Na (up to 300%) and K concentration (up to 320%) at the beginning of jug filter usage was reported. A decrease in Ca, Fe and Zn concentration was observed. Standard filters remove 80–90% of Mg from tap water at the beginning of the usage, while magnesium-enriching ones slightly increase its concentration – from around 8 to 12–25 mg/L. Significant changes in the filter’s operating characteristics were also observed for other studied elements as they wore out. Using Mg-enriching filters can increase magnesium intake from 4–5 to 6–15% of the recommended daily dose from water consumption. The results were also discussed regarding the amounts of macroelements found in commercially available bottled water. The magnesium concentration in tap water after filtration through magnesium-enriching filters was lower compared to bottled mineral waters. The authors note a scope for the development of water filter production technology, in particular, the need to develop filters that more efficiently enrich water with magnesium and do not increase sodium concentration

  • The Effect of Varying the Light Spectrum of a Scene on the Localisation of Photogrammetric Features
    • Paweł Burdziakowski
    2024 Remote Sensing

    In modern digital photogrammetry, an image is usually registered via a digital matrix with an array of colour filters. From the registration of the image until feature points are detected on the image, the image is subjected to a series of calculations, i.e., demosaicing and conversion to greyscale, among others. These algorithms respond differently to the varying light spectrum of the scene, which consequently results in the feature location changing. In this study, the effect of scene illumination on the localisation of a feature in an image is presented. The demosaicing and greyscale conversion algorithms that produce the largest and smallest deviation of the feature from the reference point were assessed. Twelve different illumination settings from polychromatic light to monochromatic light were developed and performed, and five different demosaicing algorithms and five different methods of converting a colour image to greyscale were analysed. A total of 300 different cases were examined. As the study shows, the lowest deviation in the polychromatic light domain was achieved for light with a colour temperature of 5600 K and 5000 K, while in the monochromatic light domain, it was achieved for light with a green colour. Demosaicing methods have a significant effect on the localisation of a feature, and so the smallest feature deviation was achieved for smooth hue-type demosaicing, while for greyscale conversion, it was achieved for the mean type. Demosaicing and greyscale conversion methods for monochrome light had no effect. The article discusses the problem and concludes with recommendations and suggestions in the area of illuminating the scene with artificial light and the application of the algorithms, in order to achieve the highest accuracy using photogrammetric methods.

  • The experimental and numerical investigation of fracture behaviour in PMMA notched specimens under biaxial loading conditions – Tension with torsion
    • Elżbieta Bura
    • Wojciech Grodzki
    • Andrzej Seweryn
    2024 Pełny tekst ENGINEERING FRACTURE MECHANICS

    This paper presents the results of experimental fracture test of flat PMMA specimens under biaxial loading condition tension with torsion (proportional). The specimens were made in two thicknesses: 5 and 15 mm and were weakened with V-type edge notches with different root radii: 0.5; 2 and 10 mm. Thanks to the ARAMIS 3D 4 M non-contact vision system, measurement of the elongation and twist angle were recorded. During experimental part all of the deformation processes were observed using PHANTOM cameras. Obtained records made it possible to precisely indicate the moment of crack initiation (tensile force and torsional moment values). Using the microscopic observations the location of crack initiations were determined. Results obtained for biaxial loading were compared with those obtained for uniaxial tension and torsion. Based on experimental data the numerical calculation with FEM were carried out. The principal stress and plastic strain distribution under critical load, were obtained. The points of occurrence of stress maxima and plastic strain were indicated, which were taken as potential crack initiation sites. On the basis of the stress and plastic strain values measured at the critical points, a stress–strain fracture criterion was formulated, which was then positively verified. Additionally, new form of stress–strain fracture criterion was proposed. The bilinear form of the fracture criterion can be successfully used to predict fracture in PMMA flat specimens, regardless of the notch root radius, type of load or element thickness.

  • The exposure to UV filters: Prevalence, effects, possible molecular mechanisms of action and interactions within mixtures
    • Alexandra Rafeletou
    • Jenni Viivi Linnea Niemi
    • Francisco Alejandro Lagunas-Rangel
    • Wen Liu
    • Błażej Kudłak
    • Helgi B. Schiöth
    2024 SCIENCE OF THE TOTAL ENVIRONMENT

    Substances that can absorb sunlight and harmful UV radiation such as organic UV filters are widely used in cosmetics and other personal care products. Since humans use a wide variety of chemicals for multiple purposes it is common for UV filters to co-occur with other substances either in human originating specimens or in the environment. There is increasing interest in understanding such co-occurrence in form of potential synergy, antagonist, or additive effects of biological systems. This review focuses on the collection of data about the simultaneous occurrence of UV filters oxybenzone (OXYB), ethylexyl-methoxycinnamate (EMC) and 4-methylbenzylidene camphor (4-MBC) as well as other classes of chemicals (such as pesticides, bisphenols, and parabens) to understand better any such interactions considering synergy, additive effect and antagonism. Our analysis identified >20 different confirmed synergies in 11 papers involving 16 compounds.

  • “The Guardians of the Truth”: Journalists’ Resistance to the Algorithmization of Journalism
    • Jan Kreft
    • Monika Boguszewicz-kreft
    • Mariana Fydrych
    2024 Pełny tekst ETHOS. KWARTALNIK INSTYTUTU JANA PAWŁA II KUL

    Regardless of the term used, be it “robot journalism,” “automated journalism,” “algorithmic journalism” or “machine-written journalism,” the process of automatic content creation and distribution is progressing in the newsrooms. Meanwhile, exercising control over the creation and distribution of news is considered a fundamental element of journalists’ professional identity. The article presents the results of research on the perception of algorithmic content creation conducted among journalists in the context of their professional values and identity. The research was conducted with a qualitative method using a semi-structured interview technique with 18 journalists employed in leading Polish media. According to the study, algorithmic journalism is perceived by journalists primarily in the context of posing a threat to the fundamental journalistic principle of providing true information: what they bring to the fore is the potential for creating and spreading fake news. The respondents, who defended their journalistic professional identity, compared the disadvantages of algorithmic journalism with the unique competences of “human” journalists, perceiving the latter as advocates of concern for the quality standards of social discourse and as “guardians of the truth”.

  • The impact of China’s One-Belt One-Road initiative on international trade and global value chains
    • Yuxin Lu
    • Joanna Wolszczak-Derlacz
    2024 Asia-Pacific Journal of Accounting & Economics

    This study examines the potential effects of China’s ‘One-Belt One-Road’initiative (OBOR) on trade flows and global value chain (GVC) connections.The empirical analysis is based on the augmented trade gravity model, which comprises 186 economies and 199 of their partners from 2000 to 2018. We also estimate the gravity model for involvement in GVC (domestic value added in intermediate exports, foreign value added in exports, and one country’s contributed value in another’s total exports). OBOR proves to be positively correlated with international trade and GVC, while some corridors seem to benefit more than others (e.g. China-Pakistan,China-Mongolia-Russian Federation, and Bangladesh-China-India-Myanmar).

  • The Impact of Different Drying Methods on the Metabolomic and Lipidomic Profiles of Arthrospira platensis
    • Marika Mróz
    • Karol Parchem
    • Joanna Jóźwik
    • M. Rosário Domingues
    • Barbara Kusznierewicz
    2024 Pełny tekst MOLECULES

    Drying is an inseparable part of industrial microalgae production. In this work, the impacts of eight different drying methods on the metabolome and lipidome of Arthrospira platensis were investigated. The studied drying methods were freeze drying (FD), sun drying (SD), air drying at 40 and 75 °C (AD′ and AD″), infrared drying at 40 and 75 °C (IRD′ and IRD″), and vacuum drying at 40 and 75 °C (VD′ and VD″). Results gathered by reversed-phase liquid chromatography separation coupled with high-resolution tandem mass spectrometry with electrospray ionization (RP-LC-ESI-Orbitrap HRMS/MS) analysis allowed researchers to identify a total of 316 metabolites (including lipids) in aqueous and ethanolic extracts. The compounds identified in ethanolic extracts were mainly lipids, such as neutral and polar lipids, chlorophylls and carotenoids, while the compounds identified in the aqueous extracts were mainly amino acids and dipeptides. Among the identified compounds, products of enzymatic and chemical degradation, such as pyropheophytins, monoacylglycerols and lysophosphatidylcholines were also identified and their amounts depended on the drying method. The results showed that except for FD method, recognized as a control, the most protective method was AD′. Contrary to this, VD′ and VD″, under the conditions used, promoted the most intense degradation of valuable metabolites.

  • The Impact of Drying Conditions on the Surface Color Changes of Pine Wood
    • Aleksandra Suchta
    • Jacek Barański
    • Tatiana Vilkovská
    • Ivan Klement
    • Peter Vilkovský
    2024 Pełny tekst BIORESOURCES

    The article presents the impact of drying process and selected parameters on the color changes on the surface of pine wood (Pinus sylvestris L.). Three predetermined process conditions (modes), mild, normal, and intensive, were investigated. The experiments were conducted using a semi-industrial scale dryer designed at the Gdańsk University of Technology with a loading capacity of 0.55 m3. The drying process was applied to pine wood grown in the northern part of Pomeranian region in Poland. The specimens were selected taking into consideration the radial angle of the growth rings. During each drying mode, 25 pieces of wood with dimensions (thickness, width, length) of 0.03 m, 0.2 m, and 1.5 m, respectively, were dried. The total color change (ΔE) after drying process and color saturation (h*) before and after drying processes of the wood surface was determined using the normalized CIELAB methods. The obtained results indicated that the color change of the pine wood surface increased simultaneously with the intensification of the drying process. However, the normalized wood quality after drying under intensive drying process conditions remained within the standard limits. The application of intensive drying process conditions remarkably changes the surface color of the obtained material, while remarkably reducing the drying process duration.

  • The Impact of Foreign Accents on the Performance of Whisper Family Models Using Medical Speech in Polish
    • Szymon Zaporowski
    2024

    The article presents preliminary experiments investigating the impact of accent on the performance of the Whisper automatic speech recognition (ASR) system, specifically for the Polish language and medical data. The literature review revealed a scarcity of studies on the influence of accents on speech recognition systems in Polish, especially concerning medical terminology. The experiments involved voice cloning of selected individuals and adding prosodic contours with Russian and German accents, followed by transcription of these samples using all available models from the Whisper family and comparison with the original transcription. The results of these initial experiments suggest that the Whisper model struggles with foreign accents in the context of Polish language and medical terminology. This highlights the need for further research aimed at improving ASR systems for foreign accents and medical terminology.

  • The impact of global value chains on wages, employment, and productivity: a survey of theoretical approaches
    • Sabina Szymczak
    2024 Pełny tekst Journal for Labour Market Research

    This study presents a systematic literature review to provide a collection of theories explaining the impact of global value chains (GVCs) on labour market outcomes. Due to the complex nature of GVCs and the interconnectedness of wages, employment, and productivity, many direct and indirect effects are at play. To ensure a transparent and systematic flow of the review process, I follow the PRISMA guide. Eventually, 36 records out of 1221 results from Scopus database were selected. This review may be useful for theorists, empirical economists, and policy makers as an overview of theoretical developments and convenient map of potential outcomes expected from involvement in GVCs. It identifies and systematizes a number of effects existing in the literature under various names. The results show that the predictions from the theory are ambiguous. The positive effects which may emerge regardless the characteristics of the GVC are the productivity-enhancing effect and the cross-effect, especially important considering growing servicification of manufacturing. Here lies the critical role of the state and policies to assure that the losses will not exceed the gains in the aggregate terms. One of the main factors shaping the outcome is the power distribution among the GVC’s firms. Additionally, this paper shows the shortcomings of the existing theories. Less aggregated levels of analysis could be a great input to the discussion, as well as addressing different GVCs’ dimensions and types of organisation. The understanding of relation between GVC position and labour market is especially worth exploration as the existing evidence adopt different and even contradicting perspectives on the definition of upgrading the GVC position.

  • The Impact of Hybrid Flame Retardant Compositions on the Performance of Foamed Flexible Polyurethane/Ground Tire Rubber Composites
    • Paulina Kosmela
    • Adam Olszewski
    • Mateusz Barczewski
    • Adam Piasecki
    • Aleksander Hejna
    2024 JOURNAL OF MATERIALS ENGINEERING AND PERFORMANCE

    Current sustainability-oriented trends affect polyurethane (PU) materials and stimulate the incorporation of recycled or waste-based materials as fillers. Ground tire rubber (GTR) poses as an auspicious candidate due to the excellent performance of car tires. Despite the benefits related to the mechanical performance, it contributes to the increasing flammability of the resulting composites. Herein, presented work assessed the impact of hybrid flame retardant (FR) combinations of ammonium polyphosphate (APP) or melamine cyanurate (MC) with organophosphorus compounds on the performance of foamed flexible PU/GTR composites. Such works are of vital importance, because matching to the needs of material with the mode of action of particular FRs is quite challenging. Except for the flammability reduction, they also affect structure and performance of composites. Fire resistance was enhanced for all applied FRs compositions; however, APP was found more effective than MC due to the efficient formation of protective char layer. Moreover, introduction of MC induced heterogeneity of cellular structure and excessive stiffening of PU structure, which increased its friability and cells’ coalescence, deteriorating thermal insulation performance and damping ability.