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Search results for: DEGRADABLE POLYURETHANE
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Experimental Study on Dynamics of Wooden House Wall Panels with Different Thermal Isolation
PublicationWood frame buildings are very popular in regions that are exposed to different dynamic excitations including earthquakes. Therefore, their seismic resistance is really important in order to prevent structural damages and human losses. The aim of the present paper is to show the results of experimental tests focused on the dynamic response of wall panels of a wooden frame building with thermal isolation made of mineral wool and...
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Mechanical Recycling via Regrinding, Rebonding, Adhesive Pressing, and Molding
PublicationIncreasing amount of polyurethane foams waste (e.g. from the building or furniture industry) produced every year resulted in the intensive development of their recycling methods. This chapter covers most important mechanical recycling methods, i.e. regrinding, rebonding, adhesive pressing, and molding. The procedure, required equipment and chemicals (if needed) for each method were described. The possible applications of the products...
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Auxetic foams
PublicationThis paper presents a method of producing auxetic polyurethane foams (PUFs) and their unique properties. The experience was based on a synthesis of traditional flexible polyurethane foam and thermal conversion to auxetic foam. The foam specimens were transformed from conventional Poisson's ratio to auxetic (negative Poisson's ratio) [1]. Basic research was performed to determine the mechanical properties and cell structure. Auxetic...
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MODAL ANALYSIS OF REAL TIMBER FRAME HOUSES WITH DIFFERENT INSULATION MATERIALS
PublicationThe aim of this article is to present the results of a numerical modal analysis of two actual structures of timber frame buildings and the different behaviour due to the used insulation material. One model of the timber structure was filled with mineral wool, while the other with polyurethane foam. During the modal analysis, eigenvalues for both models have been determined. The results of the analysis clearly show the increase...
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Influence of several biodegradable components added to pure and nanosilver-doped PMMA bone cements on its biological and mechanical properties
PublicationAcrylic bone cements (BC) are wildly used in medicine. Despite favorable mechanical properties, processability and inject capability, BC lack bioactivity. To overcome this, we investigated the effects of selected biodegradable additives to create a partially-degradable BC and also we evaluated its combination with nanosilver (AgNp). We hypothesized that using above strategies it would be possible to obtain bioactive BC. The Cemex...
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Experimentation, material modelling and simulation of bonded joints with a flexible adhesive
PublicationThe paper deals with material parameters identification of a flexible adhesive and the numerical simulation of its behaviour in a single lap bonded joint. The material modelling was based on the simple shear and tensile-shear laboratory tests of the bonded joints made of thin aluminium and polyurethane plates with the flexible adhesive Terostat MS 9360 manufactured by Henkel AG & Co. The adhesive was considered as a hyperelastic...
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NARAŻENIA NAPIĘCIOWE SILNIKÓW INDUKCYJNYCH ZASILANYCH Z FALOWNIKÓW NAPIĘCIA
PublicationW artykule przedstawiono zagadnienia związane z narażeniami izolacji silników pracujących w układach napędowych z falownikami napięcia. Znaczne stromości napięć oraz zjawiska falowe w przewodach zasilających powodują przyspieszoną degradacje izolacji maszyn. Rozwiązaniem jest stosowanie filtrów biernych na wyjściu falownika.
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Biopolyols obtained via microwave-assisted liquefaction of lignin: structure, rheological, physical and thermal properties
PublicationThe present study examined the application of polyols obtained via microwave-assisted liquefaction of lignin in the production of rigid polyurethane foam. Lignin was liquefed in crude glycerol and 1,4-butanediol at diferent temperatures (130–170 °C), without a catalyst and using various biomass concentrations (15 and 30 wt%). The physicochemical properties, process yield, and FTIR-based identifcation of the obtained polyols were...
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Centrum Gdańska Wrzeszcza - problem degradacji ulicy Grunwaldzkiej
PublicationGdańskw- Wrzeszcz jest jedną z najwazniejszych dzielnic Gdańska. W publikacji opisano historię ul. Grunwaldzkiej, głównej ulicy tej dzielnicy od momentu jej odbudowy po zniszczeniach wojennych w 1945 r. do końca XX w. Wskazano na zachodzące zmiany i postępującą degradacje tej ulicy.
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Prediction of the fatigue lifetime of PUR structural elements using a combined experimental-numerical approach
PublicationThis paper presents a method for estimating the fatigue life of polyurethane elastomeric components. A rubber replacement - polyurethane of hardness 80ShA commonly used in vibration damping systems, for example, in motor vehicle suspensions, was used for the study. A metal-rubber bushing component was selected for analysis, and numerical analysis was carried out along with a fatigue model proposal based on a modification of the...
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Structure and properties comparison of poly(ether-urethane)s based on nonpetrochemical and petrochemical polyols obtained by solvent free two-step method
PublicationThe application of thermoplastic polyurethanes (TPU) is becoming more and more extensive, and the decreasing of used petrochemical monomers and reduction of energy for the polymerization and processing processes is getting increasingly important. In this paper, we confirmed the positive influence of high bio-based monomers contents (by replacing petrochemical polyol and glycol by bio-based counterparts) on processing and properties...
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Novel bio-based thermoplastic poly(ether-urethane)s. Correlations between the structure, processing and properties
PublicationThe main purpose of this work was to analyze the effect of the number of unreacted isocyanate groups and the [NCO]/[OH] molar ratio during the chain extension of a prepolymer during the polymerization process on the structure, processing and selected properties of thermoplastic poly(ether-urethane)s. Three series of novel thermoplastic polyurethanes were obtained via a prepolymer route. Three prepolymers were synthesized from diisocyanate...
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Influence of nitrogen and organic matter fractions on wastewater treatment in treatment wetland
PublicationMunicipal wastewater contains both biodegradable and non-degradable pollutants. Moreover, they are present in dissolved, colloidal and particulate forms. These fractions are characterised by various decomposition rates, hence their bioavailability during microbial respiration. It was confirm that biological degradation rate in terms of COD reduction is influenced by particle size speciation. Therefore, the objective of the study...
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Timber frame houses resistant to dynamic loads - seismic analysis
PublicationThe aim of the article is to present results of seismic analysis results of two real-sized timber frame buildings subjected to seismic excitations. The first model was insulated with mineral wool, the second one with polyurethane foam. Technology and specifications involved in both models construction is based on the previously conducted experimental research on timber frame houses, including wall panels tests, wall numerical models...
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Removal efficiency of phenol by ozonation process with calcium peroxide from aqueous solutions
PublicationPhenol has been introduced as a priority pollutant by the US Environmental Protection Agency. Advanced oxidation processes (AOPs) are one of the most efcient methods for removal of non-degradable organic pollutants in aqueous solutions. The removal efciencies of phenol and COD under optimal conditions pH=3, phenol concentration=5 mg/L, CaO2 concentration=0.025 mg/L, temperature 25 °C, 1 g/min ozonation rate and contact time=90...
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Pilot study of the influence of thermoplastic starch based polymer packaging material on the growth of diatom population in sea water environment
PublicationNovel polymeric packaging materials susceptible to environmentally friendly decomposition appeared on the global market. The paper is devoted to an investigation of the impact of degradable polymer packaging on marine life. The chosen polymer was a commercial packaging based on thermoplastic starch (TPS over 85%). The microorganism chosen was Phaeodactylum tricornutum diatom (identified in many aquatic reservoirs, with a tendency...
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Risks related to car fire on innovative Poroelastic Road Surfaces-PERS
PublicationTo reduce tyre/road noise, the concept of poroelastic road surfaces (PERS) was invented. PERS is a road surface material that is porous, and at the same time, it is flexible because of the substantial amount of rubber granulate content (from 20% to 85%). The rubber and stone particles are bound by polyurethane resin instead of bitumen. It was feared that in case of fire, because of the high content of rubber and polyurethane, there...
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Synthesis, structure and properties of novel poly(hydroxyurethane)s obtained by non-isocyanate route
PublicationNon-isocyanate polyurethanes (NIPUs) can be synthesized by polyaddition of five-membered bis(cyclic carbonate)s and primary diamines. NIPUs are an alternative for the commonly used (in the form of foams, elastomers, coatings or fibers) in the industry polyurethanes obtained using toxic and moisture sensitive diisocyanates, polyols and low-molecular weight chain extenders. The main aim of this work was to synthesize non-isocyanate...
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New-fangled sources of cellulose extraction: comparative study of the effectiveness of Cissus latifolia and Ficus benghalensis cellulose as a filler
PublicationRecycled polymers and biopolymers are receiving a great deal of attention these days. If these two can be combined, it will lead to an environment-friendly green material with a great deal of applications. Here the present work is about incorporating bio-based fillers in a recycled polyurethane matrix. Two unusual and extremely novel sources of cellulose have been proposed. The celluloses obtained from Cissus latifolia and Ficus...
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Assessment of the impact of bacteria Pseudomonas denitrificans, Pseudomonas fluorescens, Bacillus subtilis and yeast Yarrowia lipolytica on commercial poly(ether urethanes)
PublicationThe assessment of the impact of the bacteria Pseudomonas denitrificans, Pseudomonas fluorescens, Bacillus subtilis and yeast Yarrowia lipolytica on commercial poly(ether urethanes) Tecoflex® and Tecothane® is presented. The polyurethane samples were incubated with pure cultures of the microorganisms at 30 °C for five months. The changes in the chemical structure of the polymers were evaluated using loss of weight and contact angle...
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Low Noise Poroelastic Road Pavements Based On Bituminous Binder
PublicationTire/road noise is the dominant source of traffic noise. It depends both on the tire design and on the characteristics of road pavements as well as on the vehicles’ operating conditions. Due to the fact that conventional (pneumatic) car tires have almost reached the limits of their ability to further reduce their noisiness, it is widely believed that the additional reduction of tire noise will be possible mainly through modifications...
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The Influence of Substitution of a Phosphorus-Containing Polyol with the Bio-polyol on the Properties of Bio-based PUR/PIR Foams
PublicationIn this work, effects of incorporating of a phosphorus-containing polyol into rigid polyurethane/polyisocyanurate foams’ formulations developed with use of two different bio-based polyols, derived from crude glycerol or liquefied cellulose were examined. The bio-polyol derived from crude glycerol was synthesized via two-step process from crude glycerol and castor oil, whereas the bio-polyol derived from liquefied cellulose was...
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Synteza, struktura chemiczna i właściwości bezizocyjanianowych poliuretanów otrzymywanych z wykorzystaniem CO2 oraz surowców pochodzenia naturalnego.
PublicationZ uwagi na wciąż rosnącą świadomość proekologiczną, politykę zrównoważonego rozwoju, a także nurt zielonej chemii wiodącym trendem w przemyśle tworzyw sztucznych jest poszukiwanie alternatywnych metod otrzymywania materiałów polimerowych. Komercyjnie poliuretany otrzymywane są w wyniku reakcji poliaddycji di- lub poliizocyjanianów z poliolami i małocząsteczkowymi przedłużaczami łańcucha. Z uwagi na niekorzystne właściwości diizocyjanianów,...
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The role of SSVF and SSHF beds in concentrated wastewater treatment, design recommendation
PublicationThe return flows of reject water from sewage sludge dewatering alter the activated sludge process ina conventional WWTP and increase TN concentration in the final effluent from WWTP. The objectiveof the investigation carried out was to consider the application of multistage treatment wetland(MTW) for the treatment of reject water from sewage sludge dewatering in a centrifuge (RWC). Thispaper aims to present the design and performance...
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Mathematical Modeling of the Impact Range of Sewage Discharge on the Vistula Water Quality in the Region of Włocławek
PublicationThe paper presents results of analysis of the industrial sewage discharge influence at km 688 + 250 of the Vistula River on water quality. During the analysis, two-dimensional models of flow, impurities and temperature transport were used. Hydrological conditions of the analyzed section of the river, characteristic flows and bathymetry of the riverbed in the first instance were defined. Calculations of velocity distribution at...
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Developing Materials for Biodegradable Otolaryngological Stents
PublicationMaterials for otolaryngological stents have to be characterized by good tensile strength, wear resistance, biocompatibility, and specific degradation time. This work aimed to synthesize polyurethanes based on various biodegradable polyol blends. Their biodegradability and mechanical properties were tested and compared to commercial BIOFLEX material.
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Istotność procesu selekcji przy wykorzystaniu algorytmów genetycznych do diagnostyki cieplno-przepływowej
PublicationArtykuł ten ma za zadanie przedstawić istotność zastosowania procesu selekcji przy diagnozowaniu turbin parowych. Możliwość zastosowania algorytmów genetycznych w diagnostyce cieplno-przepływowej wiąże się z zastosowaniem selekcji występujących parametrów, proces selekcji jest najtrudniejszy ze względu na liczbę parametrów. Liczba degradujących się parametrów może być różna tzn. możemy mówić o degradacji jednokrotnej lub wielokrotnej....
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The role of SSVF and SSHF beds in concentrated wastewater treatment, design recommendation
PublicationThe return flows of reject water from sewage sludge dewatering alter the activated sludgeprocess in a conventional WWTP and increas TN concentration in final effluent from WWTPs.The objectives of the investigation carried out is to consider the application of sequential SS VFbeds and an SS HF bed for the treatment of highly polluted wastewater, namely reject waterfrom sewage sludge dewatering in a centrifuge (RWC). This paper aims...
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Maillard-reaction (glycation) of biopolymeric packaging films; principles, mechanisms, food applications
PublicationBackground The biodegradable, biocompatible, sustainable, and renewable nature of biomaterials has led to increased interest in developing biopolymeric food packaging films (BFPFs) with green ingredients and strategies. To enhance the performance of these films, biopolymer molecules can be modified or combined with additives like nanomaterials, cross-linkers, bioactive compounds, and other polymers, particularly with Maillard-reaction...
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Comparison of the Efficiency of Hetero- and Homogeneous Catalysts in Cellulose Liquefaction
PublicationBiomass liquefaction is a well-known and extensively described process. Hydrothermal processes are well understood and can be used in the fuel industry. The use of organic solvents can result in full-fledged products for use in the synthesis of polyurethanes. The plastics industry, including polyurethanes, is targeting new, more environmentally friendly solutions. One of these is the replacement of petrochemical polyols with compounds...
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Modeling of wood frame structures with different insulation materials under damaging dynamic loading
PublicationWood frame buildings are very popular in regions that are exposed to different dynamic excitations, such as damaging earthquakes. Their seismic resistance is really important in order to prevent structural damages and human losses. This paper presents the results of advanced numerical investigation carried out using the FEM. Based on the models of wall panels, the numerical model of real structure of the wood frame building has...
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Numerical Analysis of an Impact of Planned Location of Sewage Discharge on Natura 2000 Areas – The Dead Vistula Region Case Study
PublicationThis article presents results of an analysis of impact of a designed discharge of contaminated water into the Dead Vistula (Wisła Martwa) in the region of the Isthmus (Przesmyk) with the aim of determination of a possible effect of the pollution onto protected areas of Natura 2000 (bird habitats and sites, especially the Bird Paradise – Ptasi Raj) nature reserve. The analysis was conducted on the basis of the two-dimensional modelling...
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Fault detection in measuring systems of power plants
PublicationThis paper describes possibility of forming diagnostic relations based on application of the artifical neural networks (ANNs), intended for the identifying of degradation of measuring instruments used in developed power systems. As an example a steam turbine high-power plant was used. And, simulative calculations were applied to forming diagnostic neural relations. Both degradation of the measuring instruments and simultaneously...
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Synthesis, structure and properties of poly(ester-urethane)s obtained using bio-based and petrochemical1,3-propanediol and 1,4-butanediol
PublicationIn this paper, the poly(ester-urethane)s obtained using petrochemical and bio-based chain extenders were prepared and characterized. The influence of glycols’ origin on the chemical structure, mechanical and thermal properties of the prepared polyurethanes was studied. The materials were synthesised by prepolymer method. The first step involved the reaction of α,ω-dihydroxy(ethylene-butylene adipate (POLIOS 55/20) with 4,4’-diphenylmethane...
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Chemical structures, rheological and physical properties of biopolyols prepared via solvothermal liquefaction of Enteromorpha and Zostera marina biomass
PublicationIn this work, liquefied biomass from the Baltic Sea was used for the preparation of rigid polyurethane (PUR) foams. The biomass contained 10 wt% of Enteromorpha macroalgae and 90 wt% of Zostera marina seagrass characterized by a high content of cellulose. The influence of time, temperature and the type of solvent on the efficiency of the liquefaction process and properties of biopolyols was determined. Obtained materials were analyzed...
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Impact of influent wastewater quality on nitrogen removal rates in multistage treatment wetlands
PublicationNitrogen removal in treatment wetlands is influenced by many factors, and the presence of electron donors (biodegradable organic matter) and electron acceptors (nitrate ions) is the main limiting one; for obtaining these conditions, multistage treatment wetlands (MTWs) are required, where an extensive nitrification can be obtained in the first stages under aerobic conditions leaving then to the following anoxic/anaerobic stages...
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GOOD HEALTH PRODUCTS AND POLYMER COMPOSITES OBTAINED WITH THE USE OF NATURAL ORIGIN MICRO- AND NANOFIBERS
PublicationThe aim of this work was focused on good health products and polymer composites obtained with the use of natural origin micro- and nanofibers. Many different type of the natural plants are used in the production of good health products and polymer processing like curcuma, cellulose, microalgae and others. Often are used as a antioxidants and fillers. In this work the effect of algae and cellulose as a microfillers on the chosen...
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Novel Biomass-Based Polymers: Synthesis, Characterization, and Application
PublicationA wide range of polymers were prepared from biomass-derivatives, using different polymerization mechanisms. Well-defined, fully hydroxy-functional polyesters based on aliphatic diols were synthesized, using either conventional metal-based catalysts or the organic superbase 1,5,7-triazabicyclododecene (TBD). Unsaturated polyesters were also made, offering additional functionality to these biobased resins. Metal-catalyzed or enzymatic...
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Role of Fungi in Biodegradation of Imidazolium Ionic Liquids by Activated Sewage Sludge
PublicationIonic liquids (ILs), due to their specific properties, can play the role of persistent water contaminants. Fungi manifest the ability to decompose hardy degradable compounds, showing potential in the biodegradation of ILs, which has been studied extensively on sewage sludge; however, attention was drawn mainly to bacterial and not fungal species. The aim of the research was to determine the significance of fungi in ILs’ biodegradation...
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Wastewater treatment by means of advanced oxidation processes based on cavitation – A review
PublicationHydrodynamic and acoustic cavitation combined with advanced oxidation processes (AOPs), including, among others, the Fenton process, is a promising alternative to the technologies of wastewater treatment technologies in use today. The present review discusses processes based on cavitation combined with AOPs and evaluates their effectiveness in oxidation of organic contaminants. Complete degradation of, among others, p-nitrotoluene,...
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Lead In drinking water: Adsorption method and role of zeolitic imidazolate frameworks for its remediation: A review
PublicationDue to various characteristics properties lead(II) metal is utilized in many applications like lead ion batteries, water pipes, ammunition and paints. For this reason, concentration of lead(II) ions in water is increasing days by days which is alarming for water pollution. Water pollution is a major problem worldwide which affects biosphere badly, and causes continuous reduction of accessible sources of fresh water and ground water, available...
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Whether Carbon Nanotubes Are Capable, Promising, and Safe for Their Application in Nervous System Regeneration. Some Critical Remarks and Research Strategies
PublicationCarbon nanotubes are applied in or considered for different fields of medicine. Among them is the regeneration or rebuilding of nervous system components, which still lack substantial progress; this field is supported by carbon nanotubes to a great extent as the principal material. The limited research on this issue has involved PU/silk/MWCNTs, PCL/silk/MWCNTs, PCL/PGS/CNTs, chitin/CNTs, PGF/CNTs, CNTs/PGFs/PLDLA,MWCNTs chitosan,MWCNTs/PPy,...
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The porosity and morphology of PU foams prepared by solvent casting/salt leaching method with different solvents
PublicationIn this study, the polyurethane (PU) system based on poly(ethylene-butylene) adipate diol, 1,6-hexamethylene diisocyanate, 1,4-butanediol and ascorbic acid is used to prepare a foamed material. Polymer foams were created using solvent casting/salt-particle leaching (SC/PL) method. The influence of the PU concentration in different solutions [either in a DMF or in DMF with THF as a co-solvent] on the morphology and porosity of the...
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Podatność na degradację poliuretanów z syntetycznym polihydroksymaślanem w środowisku utleniającym i hydrolitycznym
PublicationPoliuretany (PURs), zawierające w segmencie giętkim ataktyczny, telecheliczny poli([R,S]-3-hydroksymaślan) (a-PHB) oraz polikaprolaktonodiol (PCL) lub polioksytetrametylenodiol (PTMG), poddano degradacji hydrolitycznej i oksydacyjnej. Poliuretany poddano degradacji hydrolitycznej w buforze fosforanowym z dodatkiem NaN3 w czasie 36 tygodni oraz oksydacyjnej w roztworze CoCl2/H2O2 w czasie 16 tygodni inkubacji. Próbki inkubowano...
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Recent Advances in Development of Waste-Based Polymer Materials: A Review
PublicationLimited petroleum sources, suitable law regulations, and higher awareness within society has caused sustainable development of manufacturing and recycling of polymer blends and composites to be gaining increasing attention. This work aims to report recent advances in the manufacturing of environmentally friendly and low-cost polymer materials based on post-production and postconsumer wastes. Sustainable development of three groups...
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Polyisocyanates from Sustainable Resources
PublicationIsocyanates, next to polyols, constitute the major components essential for polyurethane (PU) production. They have a significant impact on physicochemical, mechanical, and thermal properties of PU materials. They also have an impact on those materials’ purposes, forms, textures, and other features. The available and used isocyanates are of a petrochemical origin. With the development of a trend toward green chemistry in the science...
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A Simple Replica Method as the Way to Obtain a Morphologically and Mechanically Bone-like Iron-Based Biodegradable Material
PublicationPorous iron-based scaffolds were prepared by the simple replica method using polyurethane foam as a template and applying the sintering process in a tube furnace. Their surface morphology was characterized using scanning electron microscopy (SEM) and phase homogeneity was confirmed using X-ray diffraction (XRD). Corrosion behavior was determined using immersion and potentiodynamic polarization methods in phosphate buffered saline...
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Two-step Conversion of Crude Glycerol Generated by Biodiesel Production into Biopolyols: Synthesis, Structural and Physical Chemical Characterization
PublicationIn this work biopolyols were synthesized via two-step process from crude glycerol and castor oil. For better evaluation of analyzed process, the impact of its time and temperature on the structure and properties of biopolyols was determined. Obtained results fully justified conducting of synthesis in two steps. Prepared materials were characterized by hydroxyl value and water content comparable to polyols industrially applied in...
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Evaluation of Immobilization of Selected Peat-Isolated Yeast Strains of the Species Candida albicans and Candida subhashii on the Surface of Artificial Support Materials Used for Biotrickling Filtration
PublicationThe paper describes the process of n-butanol abatement by unicellular fungi, able to deplete n-butanol content in gas, by using n-butanol as source of carbon. Isolated and identified fungi species Candida albicans and Candida subhashii were subjected to a viability process via assimilation of carbon from hydrophilic and hydrophobic compounds. The isolates, which exhibited the ability to assimilate carbon, were immobilized on four...
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Influence of chemical structure on physicochemical properties and thermal decomposition of the fully bio-based poly(propylene succinate-co-butylene succinate)s
PublicationIn this work, two polyesters and four copolyesters were studied. All materials were synthesized to obtain the monomers dedicated for thermoplastic polyurethane elastomers. For this type of PUR, the monomers should characterize by appropriate selected physicochemical properties and macromolecular structure distribution, which depends on synthesis conditions. The study of chemical structure with extensive and knowledgeable analysis...