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Wyniki wyszukiwania dla: bio-based thermoplastic polyurethane elastomers
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Morphology and mechanical properties of polyamide/clay nanocomposites toughened with NBR/NBR-g-GMA: A comparative study
PublikacjaThis work highlights the importance of nanoclay dispersion state in the nanocomposites containing polyamide 6 (PA6), nanoclay and elastomers as well as clay localization at the interface of thermoplastic/elastomer. Morphology and mechanical properties of a series of nanocomposites containing acrylonitrile butadiene rubber (NBR), glycidyl methacrylate-grafted NBR (NBR-g-GMA), and combined NBR/NBR-g-GMA were compared and discussed...
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Polyurethane Nanocomposites Containing Reduced Graphene Oxide, FTIR, Raman, and XRD Studies
PublikacjaRecently, graphene and other graphene-based materials have become an essential part of composite science and technology. Their unique properties are not only restricted to graphene but also shared with derivative compounds like graphene oxide, reduced graphene oxide, functionalized graphene, and so forth. One of the most structurally important materials, graphene oxide (GO), is prepared by the oxidation of graphite. Though removal...
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Green thermoplastic poly(ether-urethane)s – synthesis, chemical structure and selected properties investigation
PublikacjaThis work aimed to characterize the effect of the monomers chemical structure on the selected properties of the green thermoplastic poly(ether-urethane)s. During synthesis two types of polyether biopolyols, 4,4′-diphenylmethane diisocyanate and bio-based 1,3-propanediol were employed. Materials were synthesized with the use of two step method and two different prepolymers, which were mixed together in equimolar quantities. Obtained...
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Interfacially modified LDPE/GTR composites with non-polar elastomers: From microstructure to macro-behavior
PublikacjaThis paper provides some new insights into the mechanism of interaction and modifications in thermoplastic composites based on low density polyethylene (LDPE), ground tire rubber (GTR) and non-polar elastomer. The composites were prepared using a co-rotating twin-screw extruder at variable LDPE/GTR ratio and constant elastomer content. Two types of commercial elastomer were applied: styrene-butadiene-styrene (SBS) block copolymers (Kraton®)...
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Liquefaction of alder wood as the source of renewable and sustainable polyols for preparation of polyurethane resins
PublikacjaLiquefaction of wood-based biomass gives different polyol properties depending on the reagents used. In this article, alder wood sawdust was liquefied with glycerol and poly(ethylene glycol) solvents. Liquefaction reactions were carried out at temperatures of 120, 150 and 170 °C. The obtained bio-polyols were analyzed in order to establish the process efficiency, hydroxyl number, acid value, viscosity and structural characteristics...
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Environmental impact and industrial development of biorenewable resources for polyurethanes
PublikacjaPolyurethanes are among the most developed types of polymers. They are produced from the three primary components, i.e., polyols, low-molecular-weight glycols used as chain extenders, and diisocyanates. Until recently, all these substrates have been obtained via petrochemical processes. A decrease in petroleum-based resources and new ecological trends in chemistry, chemical technology, and materials engineering have generated increasing...
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Bio‐polyols synthesized by liquefaction of cellulose: Influence of liquefaction solvent molecular weight
PublikacjaCurrently, the plastics industry including polyurethanes is based on the use of petrochemicals. For this reason, scientists are looking for new types of renewable resources for the substitution of petrochemical substances. This work aims to evaluate the effect of polyethylene glycols (PEG) with different molecular mass impact on properties of bio-based polyols synthesized via biomass liquefaction of cellulose. To date, research...
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Microcrystalline Cellulose Management in the Production of Poly(ether-urethane)s- Structure, Morphology, and Thermal Characteristic
PublikacjaIn response to the demand of polymer industry for reducing the use of synthetic chemicals, eco-friendly materials are investigated. In the presented study, bio-based poly(ether-urethane)s were prepared by using microcrystalline cellulose (MCC) and polyether polyol and 1,3-propanediol derived from corn sugar. A step towards sustainability was taken by incorporating bio-based compounds and cellulose, consequently, bio-waste are utilized...
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Investigation of Thermoplastic Polyurethanes Synthesized via Two Different Prepolymers
PublikacjaThe man aim of this work was to investigate the effect of the molecular weight of polyols, mixture of prepolymers, and [NCO]/[OH] molar ratio used during the prepolymer chain extending step on the chemical structure, thermomechanical and mechanical properties, and thermal stability of thermoplastic poly(ether-urethane)s In this work thermoplastic poly(ether-urethane)s were synthesized by using polyols with a various molecular weight,...
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Enhancement of PUR/PIR foam thermal stability after addition of Zostera marina biomass component investigated via thermal analysis and isoconversional kinetics
PublikacjaIn the present work, a thorough thermogravimetric (TG) analysis of bio-based polyurethane–polyisocyanurate (PUR–PIR) foams in both nitrogen and oxygen atmosphere is performed. A sustainable element of the foam is a biopolyol obtained via acid-catalyzed liquefaction of Zostera marina and Enteromorpha Algae biomass. Based on isoconversional analysis and apparent activation energies, several conclusions are obtained. In contradiction...
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Biopolyols obtained via microwave-assisted liquefaction of lignin: structure, rheological, physical and thermal properties
PublikacjaThe 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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Green TPUs from Prepolymer Mixtures Designed by Controlling the Chemical Structure of Flexible Segments
PublikacjaThis study concerns green thermoplastic polyurethanes (TPU) obtained by controlling the chemical structure of flexible segments. Two types of bio-based polyether polyols—poly(trimethylene glycol)s—with average molecular weights ca. 1000 and 2700 Da were used (PO3G1000 and PO3G2700, respectively). TPUs were prepared via a two-step method. Hard segments consisted of 4,4?- diphenylmethane diisocyanates and the bio-based 1,4-butanodiol...
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Characterization and properties of LDPE/(ground tire rubber)/crosslinked butyl rubber blends
PublikacjaIn recent years, interest in used rubber recycling, mainly focusing on the utilization of end-of-life tires, has heightened. This interest, is owing to the activities related to environmental protection and economic factors, which both stimulate companies to reuse the high-quality rubber present in ground rubber scrap. In this study, the application of crosslinked butyl rubber in thermoplastic compositions of low-density polyethylene...
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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
PublikacjaRecycled 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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Thermal and Mechanical Behavior of Elastomers Incorporated with Thermoregulating Microcapsules
PublikacjaPolyurethane (PU) is one of the principal polymers in the global plastic market thanks to its versatility and continuous improvement. In this work, PU elastomeric materials having thermoregulating properties through the incorporation of microcapsules (mSD-(LDPE·EVA-RT27)) from low-density polyethylene and vinyl acetate containing paraffin®RT27 as PCM were produced. Elastomers were synthesized while varying the molar ratio [NCO]/[OH]...
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Thermoplastic polyurethanes derived from petrochemical or renewable resources: A comprehensive review
PublikacjaThermoplastic polyurethanes (TPUs) materials are obtained by the reaction of polyol (ether-, ester-, and carbonate-based diols with average molecular weight in the range from 1,000 to 3,000 g/mol) with aliphatic or aromatic diisocyanates. Synthesized materials consist of the hard and soft segments which are separated in different level. All mechanical and thermal properties of TPUs depend on the chemical structure of used monomers,...
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Synthesis and characterization of biopolyols through biomass liquefaction of wood shavings and their application in the preparation of polyurethane wood composites
PublikacjaThe sustainability of production systems in wood processing, wood industry, and wooden waste disposal is an important issue for European industry and society. Proper development of products based on renewable wood resources gives an opportunity to provide materials with long-term environmental, social, and economic sustainability. This study aims to establish a new way of forestry and agricultural waste materials utilization by...
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Eco-Friendly Ether and Ester-Urethane Prepolymer: Structure, Processing and Properties
PublikacjaThis study concerns bio-based urethane prepolymers. The relationship between the chemical structure and the thermal and processing parameters of bio-based isocyanate-terminated ether and ester-urethane prepolymers was investigated. Bio-based prepolymers were obtained with the use of bio-monomers such as bio-based diisocyanate, bio-based polyether polyol or polyester polyols. In addition to their composition, the bio-based prepolymers...
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Composite Polyurethane-Polylactide (PUR/PLA) Flexible Filaments for 3D Fused Filament Fabrication (FFF) of Antibacterial Wound Dressings for Skin Regeneration
Publikacjahis paper addresses the potential application of flexible thermoplastic polyurethane (TPU) and poly(lactic acid) (PLA) compositions as a material for the production of antibacterial wound dressings using the Fused Filament Fabrication (FFF) 3D printing method. On the market, there are medical-grade polyurethane filaments available, but few of them have properties required for the fabrication of wound dressings, such as flexibility...
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Assessment of dynamic characteristics of thin cylindrical sandwich panels with magnetorheological core
PublikacjaBased on the equivalent single-layer linear theory for laminated shells, free and forced vibrations of thin cylindrical sandwich panels with magnetorheological core are studied. Five variants of available magnetorheological elastomers differing in their composition and physical properties are considered for smart viscoelastic core. Coupled differential equations in terms of displacements based on the generalized kinematic hypotheses...
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The effect of polyamide PA12 and polyester PBT blocks' lengths on the structure and propertries of multiblock terpoly(amide-block-ester-block-amide) (TPAEA)
PublikacjaThe ternary multiblock system terpoly(amide-b-ester-b-amide) (TPAEA) of the chemical structure: poly[(oligoamide-6.36)-block-(tetramethylene terephthalate)-block-laurolactam)] -(PA6.36-b-PBT-b-PA12)n- has been obtained (Table 1). In this system the third component (PBT block here), characterized with the proper molecular weight, is dissolved in hard phase of PA12 blocks and partially dissolved in soft phase of PA6.36. The effects...
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Mater-Bi/Brewers’ Spent Grain Biocomposites—Novel Approach to Plant-Based Waste Filler Treatment by Highly Efficient Thermomechanical and Chemical Methods
PublikacjaThermoplastic starch (TPS) is a homogenous material prepared from native starch and water or other plasticizers subjected to mixing at a temperature exceeding starch gelatinization temperature. It shows major drawbacks like high moisture sensitivity, poor mechanical properties, and thermal stability. To overcome these drawbacks without significant cost increase, TPS could be blended with bio-based or biodegradable polymers and...
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PLA–Potato Thermoplastic Starch Filament as a Sustainable Alternative to the Conventional PLA Filament: Processing, Characterization, and FFF 3D Printing
PublikacjaThe growing popularity of the fused filament fabrication (FFF) 3D printing technology in science, industry, and in-home use is associated with an increased demand for high-quality polymer filaments. This study presents an in-depth characterization and analysis of a self-made bio-based polylactide (PLA)/thermoplastic potato starch (TPS) filament dedicated for the FFF 3D printing technology. The obtained results were compared with...
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Chitosan-based inks for 3D printing and bioprinting
PublikacjaThe advent of 3D-printing/additive manufacturing in biomedical engineering field has introduced great potential for the preparation of 3D structures that can mimic native tissues. This technology has accelerated the progress in numerous areas of regenerative medicine, especially led to a big wave of biomimetic functional scaffold developments for tissue engineering demands. In recent years, the introduction of smart bio-inks has...
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Investigation of polyurethane elastomer–steel joints using glass lacquer as an adhesive agent
PublikacjaThis article describes an innovative method of coupling polyurethane elastomer (based on polyurethane glycolysate) with constructional steel, by implementation of a Glaspur®—glass lacquer containing latent polyurethanes and monosilane adhesion promoters. The commonly applied coupling agent is Cilbond® 45SF glue or its derivatives. Additionally, glycolysate was synthesised from polyurethane waste and 1,3-propylene glycol in 6:1...
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PU Polymers, Their Composites, and Nanocomposites: State of the Art and New Challenges
PublikacjaThe chapter is a review of the polyurethane(PU)-based composites and nanocomposites. The chapter details different components in the manufacturing of PU polymers, composites, and nanocomposites. The different types of glycols, isocyanates, and catalysts that are used for the synthesis of different polyurethanes are discussed. The applications and specialties of polyurethane composites and nanocomposites are also elaborated on.
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The Effect of Polyurethane Glycolysate on the Structure and Properties of Natural Rubber/Carbon Black Composites
PublikacjaIn this work the use of polyurethane chemical recycling product (i.e. glycolysis of polyurethane waste realized with the mass excess of polymer) as a plasticizer for natural rubber-based composites was proposed. The effect of plasticizer type (napthenic oil and polyurethane foam glycolysate) and amount (2, 4, 6 or 8 parts per 100 parts of natural rubber) on the processing properties of rubber mixtures and chemical structure, swelling,...
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Microstructure–Property Relationship of Polyurethane Foams Modified with Baltic Sea Biomass: Microcomputed Tomography vs. Scanning Electron Microscopy
PublikacjaIn this paper, novel rigid polyurethane foams modified with Baltic Sea biomass were compared with traditional petro-based polyurethane foam as reference sample. A special attention was focused on complex studies of microstructure, which was visualized and measured in 3D with high-resolution microcomputed tomography (microCT) and, as commonly applied for this purpose, scanning electron microscopy (SEM). The impact of pore volume,...
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Phytoremediation—From Environment Cleaning to Energy Generation—Current Status and Future Perspectives
Publikacja:Phytoremediationis a technology based on the use of green plants to remove, relocate, deactivate, or destroy harmful environmental pollutants such as heavy metals, radionuclides, hydrocarbons, and pharmaceuticals. Under the general term of phytoremediation, several processes with distinctively different mechanisms of action are hidden. In this paper, the most popular modes of phytoremediation are described and discussed. A broad...
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Processing of Polyester-Urethane Filament and Characterization of FFF 3D Printed Elastic Porous Structures with Potential in Cancellous Bone Tissue Engineering
PublikacjaThis paper addresses the potential of self-made polyester-urethane filament as a candidate for Fused Filament Fabrication (FFF)-based 3D printing (3DP) in medical applications. Since the industry does not provide many ready-made solutions of medical-grade polyurethane filaments, we undertook research aimed at presenting the process of thermoplastic polyurethane (TPU) filament formation, detailed characteristics, and 3DP of specially...
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Termooksydacyjna i fotooksydacyjna degradacja pianek poliuretanowych
PublikacjaPrzeprowadzono ocenę efektywności działania wybranych środków przeciwstarzeniowych w sztywnych piankach poliuretanowych, otrzymywanych na drodze syntezy jednoetapowej. Ocenę tę oparto na pomia-rach zmian barwy oraz wytrzymałości mechanicznej zsyntezowanych materiałów. Na podstawie analizy uzyskanych wyników stwierdzono, iż dodatek 3% mieszaniny I rzędowego antyutleniacza fenolowego oraz benzotriazolowego absorbera UV znacząco zmniejsza...
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Biopolyols obtained via crude glycerol-based liquefaction of cellulose: their structural, rheological and thermal characterization
PublikacjaIn this work lignocellulose biomass liquefaction was used to produce biopolyols suitable for the manufacturing of rigid polyurethane foams. In order to better evaluate the mechanism of the process, pure cellulose was applied as a raw material. The effect of time and temperature on the effectiveness of liquefaction and the parameters of resulting biopolyols were characterized. The prepared materials were analyzed in terms of their...
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Prediction of the fatigue lifetime of PUR structural elements using a combined experimental-numerical approach
PublikacjaThis 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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Selected biotrends in development of epoxy resins and their composites
PublikacjaEpoxy resins and their fibre or particulate composites are widely used in various industries, including building, naval, aircraft, automotive and aerospace. Modern polymer science and technology focus on the development of green polymers and composites. There are two major areas of interest in the case of epoxy resins: the development of bio-based resins and the production of composites with natural fibers. One of the most interesting...
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Synthesis, structure and properties of novel poly(hydroxyurethane)s obtained by non-isocyanate route
PublikacjaNon-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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Fabrication and Characterization of Flexible Medical-Grade TPU Filament for Fused Deposition Modeling 3DP Technology
PublikacjaThe possibility of using additive manufacturing (AM) in the medicine area has created new opportunities in health care. This has contributed to a sharp increase in demand for 3D printers, their systems and materials that are adapted to strict medical requirements. We described herein a medical-grade thermoplastic polyurethane (S-TPU) which was developed and then formed into a filament for Fused Deposition Modeling (FDM) 3D printers...
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Linear and branched polyester resins based on dimethyl-2,5-furandicarboxylate for coating applications
PublikacjaIn this study, novel bio-based hydroxyl-functional (co)polyesters from dimethyl-2, 5-furandicarboxylate (DMF), 2,3-butanediol, and a variety of comonomers viz. glycerol, pentaerythritol or trimethylolpropane are prepared using a solvent-free, bulk polycondensation technique. Extensive molecular and thermal characterization was performed to elucidate the properties of these materials. The materials showed suitable properties for solvent-borne...
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Renewable Resources for Polyurethanes and Polyurethane Composites: A Review
PublikacjaEach year, more than two million tons of polyurethane is produced in the EU by reacting isocyanates with polyols made from fossil fuel. In addition, there are appreciable quantities of petroleum based functional additives applied in the industry nowadays for both polyols and polyurethane materials. It is therefore of key importance to develop sustainable economically viable polyols with enhanced functionalities, and thereby reducing...
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The influence of esterification time on the physicochemical properties of poly (glycerol sebacate-co- butylene sebacate)
PublikacjaThe study presents the results of the physicochemical properties of ester elastomer based on sebacic acid, glycerol and 1,4 - butanediol. The process of obtaining elastomers at variable esterification times of 14, 16 and 21 h is described. It was found that the material with an esterification time of 21 h is characterized by the best mechanical properties while maintaining high content of the gel fraction. In the technological...
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Molecular dynamics studies of polyurethane nanocomposite hydrogels
PublikacjaPolyurethane PEO-based hydrogels have a broad range of biomedical applicability. They are attractive for drug-controlled delivery systems, surgical implants and wound healing dressings. In this study, a PEO based polyurethane hydrogels containing Cloisite R 30B, an organically modified clay mineral, was synthesized. Structure of nanocomposite hydrogels was determined using XRD technique. Its molecular dynamics was studied by means...
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MODAL ANALYSIS OF REAL TIMBER FRAME HOUSES WITH DIFFERENT INSULATION MATERIALS
PublikacjaThe 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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Progress in non-isocyanate polyurethanes synthesized from cyclic carbonate intermediates and di- or polyamines in the context of structure–properties relationship and from an environmental point of view
PublikacjaCommercially, polyurethanes are produced by the reaction of diisocyanates, polyols (polyester or polyether) and low molecular weight chain extender. Toxicity, moisture sensitivity and phosgene-based synthesis of diisocyanates resulted in investigations focused on obtaining the non-isocyanate polyurethanes (NIPUs). This work presents the review of synthesis and structure–properties relationship of non-isocyanate polyurethanes obtained...
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Fabrication and Characterization of Green Polyurethane Foams with Enhanced Vibration Damping Capability
PublikacjaOver the past decades, there has been an intensive development of the technologies and innovations aimed at increasing the quality of life. This development largely concerns the comfort of use of everyday products that, among others, are products of the automotive, construction, or furniture industries. Considering the increase in the comfort of using products such as cars, houses, and flats, one of the comfort features of their...
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Experimentation, material modelling and simulation of bonded joints with a flexible adhesive
PublikacjaThe 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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Auxetic foams
PublikacjaThis 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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Synteza, struktura chemiczna i właściwości bezizocyjanianowych poliuretanów otrzymywanych z wykorzystaniem CO2 oraz surowców pochodzenia naturalnego.
PublikacjaZ 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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Recent progress in ultra-low formaldehyde emitting adhesive systems and formaldehyde scavengers in wood-based panels: a review
PublikacjaTraditional wood-based panels are produced with synthetic, formaldehyde-based adhesives, commonly made from fossil-derived constituents, such as urea, phenol, melamine, etc. Along with their numerous advantages, such as chemical versatility, high reactivity and excellent adhesive performance, these adhesives are characterized by certain problems, connected with the hazardous volatile organic compounds (VOCs), mostly free formaldehyde...
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Timber Frame Houses with Different Insulation Materials - Seismic Analysis
PublikacjaThe aim of this article is to present results of a dynamic numerical analysis focused on the response of two timber frame building structures exposed to seismic excitations. The first structure was insulated with mineral wool, while the second one with polyurethane foam. Specifications and technology involved in the models' construction are based on the previously conducted experimental study, upon which numerical structural models...
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Timber frame houses resistant to dynamic loads - seismic analysis
PublikacjaThe 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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Development of nanoscale morphology and role of viscoelastic phase separation on the properties of epoxy/recycled polyurethane blends
PublikacjaA novel and cost-effective approach towards the modification of epoxy matrix has been developed using recycled polyurethane for the first time without sacrificing any of the intrinsic properties of the resin. Polyurethane, recycled from waste foam by glycolysis process (RPU), was found to be very effective in improving the properties of the thermosetting resin based on Diglycidyl ether of bisphenol-A (DGEBA). The effect of the...