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Search results for: SYNTHESIS OF POLYURETHANES
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Renewable Resources for Polyurethanes and Polyurethane Composites: A Review
PublicationEach 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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Polyurethanes modified with natural polymers for medical application. I. Polyurethanes/ Chitosan and polyurethane/collagen.
PublicationFor over three decades polyurethanes (PUR or PU) have been reported for application in a variety of medical devices. These polymers consist of hard and soft segments, which allow for more subtle control of their structure and properties. By varying the composition of the different segments, properties of PURcan be tuned up for use in many areas of medicine. Recently there is a great interest in modification of biomedical PUR with...
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Polyurethanes modified with natural polymers for medical application. Part II. Polyurethane/gelatin, polyurethane/starch, polyurethane/cellulose
PublicationThis paper is a literature overview of biomedical PUR modifications with natural polymers such as starch, cellulose and gelatin. Properties like biodegradability and biocompatibility of modified PUR cause that these materials may be used as wound dressings, tissue scaffolds, tissue implants and also vascular grafts.
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Thermoplastic polyurethanes with glycolysate intermediates from polyurethane waste recycling
PublicationThe polyol is a major component in polyurethane formulations and therefore introducing to the formulation recycled polyol (obtained during decomposition process) allows decreasing the usage of pure petrochemical components. In this work, thermoplastic polyurethanes were prepared using various mixtures of a petrochemical macrodiol poly(ethylene-butylene adipate)diol (PEBA) and a recycled glycolysate intermediate, called glycolysate...
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Thermal properties of polyurethanes synthesized using waste polyurethane foam glycolysates
PublicationW pracy przedstawiono wyniki analizy termicznej (DMTA i TG-FTIR) glikolizatów i otrzymanych z nich poliuretanów. Glikolizaty uzyskiwano w reakcji odpadowej pianki poliuretanowej z 1,6 heksametylenodiolem (HDO) przy różnym stosunku masowym pianki do HDO (1:1 - 10:1). Poliuretany syntezowano metodą dwuetapową z prepolimeru (diizocyjanian MDI + glikolizat), który przedłużano handlowym małocząsteczkowym glikolem.
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Synthesis and characterisation of polyurethane elastomers with semi-products obtained from polyurethane recycling
PublicationIn this work polyurethane elastomers were synthesised by using different mixtures of a petrochemical and glycerolysate polyols and 4,4-diphenylmethane diisocyanate (MDI). Glycerolysate polyol was produced from polyurethane foam decomposition using crude glycerine as a decomposition agent. The structure and thermal properties of obtained semi-product were similar to the polyol used in the synthesis of original foam. Glycerolysate...
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Synthesis and Investigation of Glycolysates and Obtained Polyurethane Elastomers
PublicationScharakteryzowano proces glikolizy poprodukcyjnych odpadów poliuretanowych przeprowadzony przy użyciu glikolu heksametylenowego. Przedstawiono niektóre właściwości fizykochemiczne otrzymanych glikolizatów. Omówiono wyniki analizy termicznej, termomechanicznej oraz budowy chemicznej metodą FTIR zsyntetyzowanych elastomerów poliuretanowych. Właściwości mechaniczne zmierzono w warunkch statycznych przy użyciu uniwersalnej maszyny...
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Synthesis and characterization of novel aliphatic polyurethanes for tissue engineering applications
PublicationSummarizing, in this thesis was described the synthesis of novel PUR system, which was obtained by using aliphatic diisocyanate (HDI), amorphous macrodiol (PEBA) and chain extender (BDO). This PUR system was established as suitable for TE purpose and successfully modified with AA, which as expected improved its biocompatibility. According to this, AA-modified HDI-based PURs is the PUR system ready for further studies including...
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Chemical modifications of natural oils and examples of their usage for polyurethane synthesis
PublicationNatural oils have been used in the production of plastics for a long time. However, the number of studies dedicated to polyurethane research has shown an increase only recently. Usually, petrochemical components are used in polyurethane synthesis. Nowadays, there have been attemptsmade to replace polyols in polyurethanes with the modified oils and other natural raw materials. It is a promising and important scenario because the...
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Evaluation of the glycerolysis process and valorisation of recovered polyol in polyurethane synthesis
PublicationIn this study, the glycerolysis of polyurethane (PU) foam and the applicability of obtained glycerolysate (GLY) for cast PUs were investigated. It was found that crude glycerine with purity grade of 84% might be successfully used for the glycerolysis. The optimal conditions were determined as follows: reaction time of 60 min at 220 °C using dibutyltin dilaurate catalyst (0.5%). Moreover, the purification of GLY by means of liquid-liquid...
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Synthesis and Physicochemical Characteristics of Chitosan-Based Polyurethane Flexible Foams
PublicationThe use of shrimp waste to obtain chitosan (Ch) is an essential issue, considering a circular economy, waste management, and its application to environmentally friendly materials. In this study, northern prawn shells were utilized to obtain Ch, which could then be used for synthesizing chitosan-based polyurethane (PUR+Ch) foams with different Ch concentration. The chemical structure, morphology, hardness, thermal properties, viscoelastic...
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The properties of polyurethanes based on synthetic polyhydroxybutyrate for medical application
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A New Approach to Chemical Recycling of Polyamide 6.6 and Synthesis of Polyurethanes with Recovered Intermediates
PublicationA new efficient method for the chemical decomposition of polyamide 6.6 by the glycolysis and amino-glycolysis processes was proposed. The glycolysis was conducted using the mass excess of ethylene glycol (EG) as a decomposing agent in the presence of a catalyst. Also, a mixture of EG and triethylenetetramine was used as another decomposing agent in the amino- glycolysis process. The described process of decomposition did not...
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The influence of synthetic polyhydroxybutyrate on selected properties of novel polyurethanes for medical applications. Part I. Polyurethanes with aromatic diisocyanates in hard segments
PublicationZsyntetyzowano poliuretany (PUR) z udziałem 37% segmentu sztywnego uzyskanego na etapie przedłużania łańcucha prepolimeru w reakcji 4,4â-diizocyjanianu difenylometanu (MDI) z 1,4-butanodiolem (1,4-BD). Segmenty giętkie wytworzonych PUR były zbudowane z poli([R,S]-3--hydroksymaoelanu) (a-PHB) i polikaprolaktonodiolu (PCL) lub z a-PHB i polioksytetrametylenodiolu(PTMG). Zbadano wpływ obecności w łańcuchu PUR syntetycznego a-PHB...
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Structure-rheology relationship of fully bio-based linear polyester polyols for polyurethanes - Synthesis and investigation
PublicationThe synthesis of polyols from renewable substances as an alternative for petrochemical-based polyols play important matter in the polyurethane industry. In this work, the fully bio-based linear polyester polyols with different catalyst amounts were synthesized via two-step polycondensation method. The effect of various catalyst content on the structure and rheological behavior were established. Fourier Transform Infrared Spectroscopy,...
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Polyurethanes
PublicationThe chapter content is devoted to Polyurethanes and consists of the following items: general characteristics of polyurethanes, raw materials used in the synthesis of crosslinked polyurethanes, synthesis and crosslinking reactions of polyurethanes, morphology of liniear and branched PU, manufacturing methods and functional properties.
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Polyurethanes
PublicationHandbook of Thermoset Plastics, Fourth Edition provides complete coverage of the chemical processes, manufacturing techniques and design properties of each polymer, along with its applications. This new edition has been expanded to include the latest developments in the field, with new chapters on radiation curing, biological adhesives, vitrimers, and 3D printing. This detailed handbook considers the practical implications of using...
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The structure of novel polyurethanes containing synthetic poly[(R,S)-3-hydroxybutyrate]
PublicationThe aim of this study was to estimate the structure of new polyurethanes with the potential to be used in medicine. Atactic poly[(R,S)-3-hydroxybutyrate], obtained via a ring-opening polymerization, and polycaprolactonediol or polyoxytetramethylenediol were used to built the soft segments. 4,4'-methylene dicyclohexyl diisocyanate and 1,4-butanediol were the components to form hard segments. Polyurethanes with low-molecular weight...
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Synthesis and characterization of cycloaliphatic hydrophilic polyurethanes, modified with l-ascorbic acid, as materials for soft tissue regeneration
PublicationIn this paper we described synthesis and characteristic of obtained hydrophilic polyurethanes (PURs) modified with ascorbic acid (commonly known as vitamin C). Such materials may find an application in the biomedical field, for example in the regenerative medicine of soft tissues, according to ascorbic acid wide influence on tissue regeneration Flora (2009), Szymańska-Pasternak et al. (2011), Taikarimi and Ibrahim (2011), Myrvik...
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Synthesis and structural characterization of bio-based bis(cyclic carbonate)s for the preparation of non-isocyanate polyurethanes
PublicationBio-based cyclic carbonates are of significant research interest as monomers for non-isocyanate polyurethane (NIPU) synthesis. This research describes the synthesis of a series of five-membered bis(cyclic carbonate)s using bio-based polyether polyols (PO3G) with different molecular weights (250, 650 and 1000 g mol−1) and carbon dioxide as green feedstocks. The utilization of CO2 as a source of carbon in the chemical reaction is...
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The mechanical properties and conduction of solid polyurethane electrolytes depending on the methods of synthesis and LiClO4 content as addition
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Degradibility in vitro of polyurethanes based on synthetic atactic poly[)R,S)-3-hydroxybutyrate
PublicationThe aim of the paper was to determine the degradibility of aliphatic polyurethanes in hydrolytic and oxidative solutions. DSC, GPC, density, polymer surface morphology were studied.
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Recycling of Polyurethanes
PublicationPolyurethane waste can be recycled by mechanical methods (i.e., grinding and applying as a filler or pressing with a bonding agent) and chemical methods (mainly by e.g., glycolysis, hydrolysis, or aminolysis). There is also possibility to the recover energy from polyurethanes waste (by incineration, gasification, and pyrolysis).
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Synthesis, physical properties and preliminary investigation of hemocompa-tibility of polyurethanes from aliphatic resources with castor oil participation
PublicationWykonano syntezy PUR z oligoeterodiolu, dioli małocząsteczkowych, oleju rycynowego i 4,4´diizocyjanianudicykloheksylometanu. Oznaczono właściwości mechaniczne PUR, kąty zwilżania i napięcie powierzchniowe. Opisano wstępne badania zgodności PUR z ludzką krwią oraz kalcyfikacji powierzchni PUR w warunkach statycznych in vitro. Napięcie powierzchniowe otrzymanych PUR jest zbliżone do napięcia powierzchniowego naturalnych powierzchni...
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Novel Cast Polyurethanes Obtained by Using Reactive Phosphorus-Containing Polyol: Synthesis, Thermal Analysis and Combustion Behaviors
PublicationPhosphorus-containing polyol applications in polyurethane synthesis can prevent volatilization of flame retardants and their migration on the surface of a material. In this work, novel cast polyurethanes were prepared by a one-step method with the use of different amounts of phosphorus-containing polyol, 4,4′–diphenylmethane diisocyanate and 1,4-butanediol. The chemical structure, thermal, physicochemical and mechanical properties...
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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
PublicationThe 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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The Green Approach to the Synthesis of Bio-Based Thermoplastic Polyurethane Elastomers with Partially Bio-Based Hard Blocks
PublicationBio-based polymeric materials and green routes for their preparation are current issues of many research works. In this work, we used the diisocyanate mixture based on partially bio-based diisocyanate origin and typical petrochemical diisocyanate for the preparation of novel bio-based thermoplastic polyurethane elastomers (bio-TPUs). We studied the influence of the diisocyanate mixture composition on the chemical structure, thermal,...
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Diamine derivatives of dimerized fatty acids and bio-based polyether polyol as sustainable platforms for the synthesis of non-isocyanate polyurethanes
PublicationA series of environmentally friendly non-isocyanate polyurethanes (NIPUs) were successfully prepared via the polyaddition reaction of bio-based polyether polyol-based cyclic carbonate with diamine derivative of dimerized fatty acids. The syntheses of NIPUs were realized by the three-step method in the absence of toxic solvents and, importantly, the process of carbonation did not require the use of elevated pressure. The effect...
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The study on application of biopolyols obtained by cellulose biomass liquefaction performed with crude glycerol for the synthesis of rigid polyurethane foams
PublicationIn this work rigid polyurethane foams (PUR) were obtained by replacement of 0–70 wt% of petrochemical polyol with bio-polyol obtained via cellulose liquefaction in presence of crude glycerol. The foams with different content of a bio-polyol were prepared by single step method for NCO/OH ratio equals 1.5. The prepared materials were analyzed in terms of their morphology, chemical structure, thermal stability and basic physical and...
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Synthesis and thermal studies of flexible polyurethane nanocomposite foams obtained using nanoclay modified with flame retardant compound
PublicationThis work presents thermal studies of nanocomposites based on the flexible polyurethane (PU) matrix and filled using montmorillonite organically modified with organophosphorus flame retardant compound. Flexible PU nanocomposite foams were prepared in the reaction carried out between reactive alcoholic hydroxyl and isocyanate groups with the ratio of NCO to OH groups equal to 1.05. The amount of an organoclay ranging from 3 to 9...
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Non-isocyanate Polyurethanes
PublicationThe main aim of this chapter is to present a general overview of the NIPU synthesis method (i.e., polycondensation and polyaddition), and to describe structure and properties of selected intermediates and final polymeric products. The focus is on five-membered ring cyclic carbonate intermediates, which were obtained by cycloaddition of carbon dioxide to selected glycidyl ethers and thiol-ene coupling of unsaturated cyclic carbonates...
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Isocyanate-Free Polyurethanes
PublicationIsocyanate-free polyurethanes (also called non-isocyanate polyurethanes, or NIPUs) are alternatives to the conventional (commercially used) polyurethanes synthesized using di- or polyisocyanates, polyols, and chain extenders with low molecular weight. The major routes of NIPUs’ synthesis involve polyaddition of cyclic carbonates and di- or polyamines, polycondensation of carbamates, and diols. The most important intermediates are...
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Nowe monomery pochodzenia roślinnego w syntezie termoplastycznych elastomerów poliuretanowych
PublicationJak dotychczas w syntezie termoplastycznych elastomerów poliuretanowych (TPU) są powszechnie wykorzystywane surowce pochodzenia petrochemicznego. Sytuacja jednak zmienia się dynamicznie i w wielu gospodarkach świata widoczne są już trendy, polegające na coraz większym wykorzystaniu substancji pochodzenia roślinnego w produkcji surowców, np. glikoli, izocyjanianów czy polioli, jako zamienników analogów syntetycznych. Praca obejmuje...
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Cast polyurethanes obtained from reactive recovered polyol intermediates via crude glycerine decomposition process
PublicationIn this work, the possibility of applying intermediates from polyurethane waste recycling in polyurethane synthesis was presented. Polyurethanes were synthesised in a two-step method using a mixture of petrochemical polyol and glycerolysate, used as a reactive component, 4,4-diphenylmethane diisocyanate (MDI) and 1,4-buthanediol (BD). Glycerolysates were produced during decomposition of polyurethane elastomer by crude glycerine...
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The changes of crosslink density of polyurethanes synthesised with using recycled component. Chemical structure and mechanical properties investigations.
PublicationThis paper aims at the utilisation of glycerolysate (Gly) obtained in polyurethane recycling process by means of crude glycerine, which has in its structure hydroxyl end groups that allow for further processing. Polyurethanes (PUs) were synthesised using prepolymer method with the mixture of neat polyol and glycerolysate, in different ratios, with 4,4-diphenylmethane diisocyanate (MDI). The prepolymer was subsequently extended...
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Recycling of Polyurethanes Containing Flame-Retardants and Polymer Waste Transformed into Flame-Retarded Polyurethanes
PublicationThe growing number of polyurethanes (PUs) produced every year has developed methods for their mechanical and chemical recycling which yield valuable products like substitutes for commercial polyols or flame-retardants. PUs can be produced in different shapes and forms (i.e., elastomers, flexible or rigid foams, coatings, etc.) using several different components (i.e., di- or polyisocyanates, ester- or ether-based polyols, low-molecular...
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Properties of PA6/thermoplastic polyurethane and PA6/polyurethane nanocomposite blends
PublicationPrzedstawiono wyniki badań właściwości i struktury mieszanin i nanokompozytów układów PA6/termoplastyczny poliuretan. W przypadku nanokompozytów wprowadzano nanonapełniacz w postaci montmorylonitu. Zbadano właściwości termiczne i wytrzymałościowe oraz omówiono wyniki analiz strukturalnych, otrzymanych z dyfrakcji rentgenowskiej i mikroskopii elektronowej.
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Development of polyurethanes for bone repair
PublicationThe purpose of this paper is to review recent developments on polyurethanes aimed at the design, synthesis, modifications, and biological properties in the field of bone tissue engineering. Different polyurethane systems are presented and discussed in terms of biodegradation, biocompatibility and bioactivity. A comprehensive discussion is provided of the influence of hard to soft segments ratio, catalysts, stiffness and hydrophilicity...
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Degradation of polyurethanes in sea water
PublicationOceniono degradowalność różnych poliuretanów w wodzie morskiej Bałtyku. Porównano te dane z wynikami stopnia degradacji poliuretanów w wodzie morskiej z dodatkiem azydku sosowego. Ocenę stopnia degradacji przeprowadzano na podstawie pomiarów zmian masy, właściwości mechanicznych i morfologii przed i po procesie degradacji. Wykazano, że różna podatność na degradację poliuretanów w wodzie morskiej związana jest z ich odmiennym stopniem...
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Polyurethanes as a carrier of drugs for gentamicin
PublicationGentamicin is one of the most popular drug and is widely used due to its antibiotic properties. 3% of world production of polyurethanes (PU) is dedicated to biomedical applications, where they can serve are parts of orthopedic prosthesis or artificial organs, disposable medical devices, wound and burn dressing, contact lenses among others. In the study, to obtain drug carriers, a combination of these two materials were prepared...
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Novel Research on Biomedical Polyurethanes
PublicationThe variety of mechanical properties characterizes properly designed PURs. They may be biocompatible and reveal compatibility with blood, making them attractive materials for the fabrication of tissue scaffolds; however, like all synthetic materials, PURs don’t reveal sufficient biocompatibility. PURs may undergo certain chemical modifications (e.g., 1,4:3,6-dianhydro-D-sorbitol, ascorbic acid (AA), growth factors, covering with...
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Comparison of disk and tube methods for estimation of biostatic properties of polyurethanes based on synthetic poly[(R,S)-3-hydroxybutyrate
PublicationThe influence of novel aliphatic polyurethanes on growth of Staphyloccocus aureus (SA)in the around of polymer samples has been estimated by disk method. It was staed that the growth of SA was inhibited.The influence of polyurethanes on planctonic Staphyloccocus aureus was also pefrormed by tube method. In this test the slight decrease of bacteria concentration was noticed.
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Natural and synthetic acridines/acridones as antitumor agents: their biological activities and methods of synthesis.
PublicationPraca stanowi przegląd opisanych w literaturze chemicznej modyfikacji struktur naturalnych i syntetycznych pochodnych akrydyny i akrydonu. Artykuł obejmuje swym zakresem metody syntezy, a także wpływ budowy cząsteczek tych związków na ich aktywność przeciwnowotworową oraz mechanizm działania.
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Polyurethanes containing organically modified clay
PublicationW pracy zaprezentowano wyniki badań dotyczące wpływu nowego, krajowego, modyfikowanego glinokrzemianu (BZ-COCO) na elastomery poliuretanowe. Dla otrzymanych układów określono podstawowe właściwości mechaniczne, termiczne oraz przeprowadzono analizę struktury.
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Bioactive polyurethanes applied as a surgical implants
PublicationSynthetic materials are applied in many branches of the industry, i.a. in medicine as a casing of apparatus, elements of artificial organs (hearts, blood vessels), catheters, wound healings, intra aortic balloons, mammary implants to mention but a few. Polymeric material used in such applications must be distinguished by a good biocompatybility. Since many years extensive research are employed to develop a new polymers that can...
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Novel Polyurethanes as Antifouling Paint Matrices
PublicationThe new poly(ester-ether urethane)s (PEEUR) were prepared in two stage synthesis from formerly obtained oligo(alkylene ester-ether)diols (OAEE) and 4,4‘-diphenylmethane diisocyanate (MDI). PEEUR samples were subjected to crosslinking with styrene in the presence of radical polymerization initiators: methyl ethyl ketone peroxide (MEKPO) or cobalt 2-ethyl cyclohexanoate (EtHCo). Crosslinked PEEUR were characterized by their physicochemical...
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Non-Isocyanate-Based Waterborne Polyurethanes
PublicationNon-isocyanate polyurethanes (NIPUs) are a greener alternative for the conventional polyurethanes synthesized using toxic and moisture-sensitive di- or polyisocyanates. The most often described method of NIPU synthesis involves the reaction of five-membered cyclic carbonates with amines, and resulting polymers containing primary and secondary hydroxyl groups (so they are also known as polyhydroxyurethanes), which can be further...
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Polyurethanes for Coating, Adhesives, and Other Applications
PublicationAn interesting group of polyurethane (PU) materials are coatings, adhesives, sealants, and thickeners. A wide base of raw materials and various methods of PU synthesis allows production of materials with a wide range of properties that can be commonly used in many industries. This chapter describes the main types of PU coatings and adhesives and special application PUs and the methods of their production. The materials described...
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Bio-Based Polyurethane Composites and Hybrid Composites Containing a New Type of Bio-Polyol and Addition of Natural and Synthetic Fibers
PublicationThis article describes how new bio-based polyol during the liquefaction process can be obtained. Selected polyol was tested in the production of polyurethane resins. Moreover, this research describes the process of manufacturing polyurethane materials and the impact of two different types of fibers—synthetic and natural (glass and sisal fibers)—on the properties of composites. The best properties were achieved at a reaction temperature...
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Characteristics of the conductivity of polyurethane nanocomposite
PublicationW opracowaniu tym przedstawiono właściwości mechaniczne oraz przewodnictwo jonowe otrzymanych nanokompozytów poliuretanowych. KOmpozyty te były otrzymane przy wykorzystaniu wytłaczarki dwuślimakowej. POddano je badaniom wytrzymałościowym, spektroskopii impedancyjnej, spektroskopii w podczerwieni oraz badaniom dynamiczno - mechanicznym (DMA)