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Search results for: BIOMEDICAL POLYURETHANES
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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)
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Shape-Memory Polyurethane Polymers
PublicationPolyurethanes (PUs) are one of the most widely used polymers in research and industry. They can be synthesized from chemical sources and natural sources. PUs are a very useful class of polymers and exhibit many desirable properties that can be exploited in various applications. PUs are formed by the reaction between polyols and isocyanates. A wide variety of polyols and isocyanates are available for synthesis, and hence we can...
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Gelatin-Modified Polyurethanes for Soft Tissue Scaffold
PublicationRecently, in the field of biomaterials, which are being designed for soft tissue scaffolding, is growing the interest of their modification with natural polymers. Synthetic polymers are often hard, not easy to process and they do not possess fine biodegradable profile. From the other hand natural polymers are biocompatible, but weak when used alone. The combination of natural and synthetic polymers gives the suitable properties...
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Degradation of polyurethanes in Compost Under Natural Conditions
PublicationThe estimation of degradibility of different polyurethanes under natural weather depending conditions in compost pile was the subject of the studies. The incubation of polymer samples took place for a period up to 24 months. The characteristic parameters of the compost: temperature, pH, moisture content, and activity of dehydrogenasis were monitored and their influence on degradation of polyuiretahnes was discussed. The compostability...
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Raman microscopy in the studies of microphase-separated polyurethanes.
PublicationPorównano możliwości badawcze różnych odmian spektroskopowych do analizy po-limerów. Podano przykłądy wykorzystania połączonych technik mikroskopowych ispektroskopowych do badania polimerów wielofazowych. Na tej podstawie wyka-zano zasadność zastosowania po raz pierwszy mikroskopii Ramana w badaniachwielofazowych poliuretanów. Wykazano różnice składu chemicznego poszczegól-nych elementów mikromorfologii wielofazowych, segmentowych...
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Morphology of polyurethanes revisited by complementary AFM and TEM
PublicationPrzedmiotem badań mikroskopowych TEM i AFM były lane segmentowe poliuretany o zawartości 30 i 50% segmentu sztywnego. Stwierdzono obecność sferolitów (poziom mikrometrów), fibryl i globul. Ponadto zastosowanie AFM pozwoliło na zbadanie nanomorfologii badanych poliuretanów. Zaobserwowano krótkie, cylindropodobne domeny segmentów sztywnych rozproszone w matrycy segmentów giętkich.
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The effect of catalyst and segmental composition on the crystallization of multiblock polyesters for biomedical applications
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Dihydroxyanthraquinones as stable and cost-effective TiO2 photosensitizers for environmental and biomedical applications
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The use of liquid crystal thermography for heat, fluid flow and biomedical research.
PublicationW ostatniej dekadzie termografia ciekłokrystaliczna (TLC) i cyfrowa analiza kolorowych obrazów była z powodzeniem stosowana w różnych aplikacjach technicznych, przemysłowych i biomedycznych. Cienkie warstwy ciekłokrystaliczne zastosowano dla uzyskania lokalnych pól temperatury, współczynników przekazywania ciepła i określenia rodzaju procesu. Materiał ciekłokrystaliczny można również zastosować do wizualizacji pól temperatury i...
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Ultrahigh-resolution detection techniques for biomedical applications of optical coherent tomography.
PublicationOptyczne metody pomiarowe odgrywają w ostatnich latach coraz większą rolę w badaniach i diagnostyce medycznej. Mają one szereg zalet, do których zaliczyć można odporność na promieniowanie elektromagnetyczne, bezinwazyjność, bezpieczeństwo pomiaru oraz wysoką rozdzielczość. Jedną z najważniejszych technik stosowanych w diagnostyce medycznej jest koherentna tomografia optyczna (OCT). Jest to wysokorozdzielcza metoda obrazowania wewnętrznych...
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Synthesis of green benzamide-decorated UiO-66-NH2 for biomedical applications
PublicationMetal-organic frameworks (MOFs) biocompatible systems can host enzymes/bacteria/viruses. Herein we synthesized a series of fatty acid amide hydrolase (FAAH)-decorated UiO-66-NH2 based on Citrus tangerine leaf extract for drug delivery and biosensor applications. Five chemically manipulated FAAH-like benzamides were localized on the UiO-66-NH2 surface with physical interactions. Comprehensive cellular and molecular analyses were...
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Proteases immobilized on nanomaterials for biocatalytic, environmental and biomedical applications: Advantages and drawbacks
PublicationProteases have gained significant scientific and industrial interest due to their unique biocatalytic characteristics and broad-spectrum applications in different industries. The development of robust nanobiocatalytic systems by attaching proteases onto various nanostructured materials as fascinating and novel nanocarriers has demonstrated exceptional biocatalytic performance, substantial stability, and ease of recyclability over...
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Preparation and Characterization of Diamond-like Carbon Coatings for Biomedical Applications—A Review
PublicationDiamond-like carbon (DLC) films are generally used in biomedical applications, mainly because of their tribological and chemical properties that prevent the release of substrate ions, extend the life cycle of the material, and promote cell growth. The unique properties of the coating depend on the ratio of the sp3/sp2 phases, where the sp2 phase provides coatings with a low coefficient of friction and good electrical conductivity,...
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LCT, PIV and IR Imaging Detection in Selected Technical and Biomedical Applications
PublicationThermochromic liquid crystals (TLC), Particle Image Velocimetry (PIV) and Infrared Imaging Themography (IR) have been successfully used in non-intrusive technical, industrial and biomedical studies and applications. These four tools (based on the desktop computers) have come together during the past two decades to produce a powerful advanced experimental technique as a judgment of quality of information that cannot be obtained...
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Liquid Crystals, PIV and IR-Photography in Selected Technical and Biomedical Applications
PublicationThermochromic liquid crystals (TLC), Particle Image Velocimetry (PIV), Infrared Imaging Themography (IR) and True-Colour Digital Image Processing (TDIP) have been successfully used in non-intrusive technical, industrial and biomedical studies and applications. These four tools (based on the desktop computers) have come together during the past two decades to produce a powerful advanced...
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LCT, PIV and IR Imaging Detection in Selected Technical and Biomedical Applications
PublicationPaper presents the brief summary of the history of Thermochromic liquid crystals (TLC), Particle Image Velocimetry (PIV) and Infrared Imaging Themography (IR). Principal methods and tools are described and some examples are presented. With this objective, a new experimental technique have been developed and applied to the study of heat and mass transfer and for biomedical diagnosis. Selected results of experiments using these methods...
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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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Fabrication of polyurethane and polyurethane based composite fibers by the electrospinning technique for soft tissue engineering of cardiovascular system
PublicationElectrospinning is the unique technique, which provides forming of polymeric scaffolds for soft tissue engineering, which include tissue scaffolds for soft tissues of cardiovascular system. Such artificial soft tissues of cardiovascular system may possess mechanical properties comparable to native vascular tissues. Electrospinning technique gives the opportu nity to form fibres with nm- to μm-scale in diameter. The arrangement...
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Fabrication of polyurethane and polyurethane based composite fibres by the electrospinning technique for soft tissue engineering of cardiovascular system
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Shape memory thin films of Polyurethane: Does graphene content affect the recovery behavior of Polyurethane nanocomposites?
PublicationThin nanocomposite films of polyurethane have received remarkable attention due to their shape memory properties. As most of the reports focus on the beneficial aspects of the presence of nanofillers such as graphene nanoplatelets (GNPs) introduced into shape memory polymers, some research results reveal the opposite trend. The polyether/polyester-based polyurethane was synthesized through a condensation polymerization and the...
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The structure and conductivity of solid polyurethane electrolyte
PublicationPrzedstawiono badania właściwości i struktury stałych elektrolitów poliuretanowych. Otrzymano je z prepolimeru zsyntezowanego z MDI oraz PTMG. Jako przedłużacz łańcucha wykorzystano butanodiol. W celu poprawy przewodnictwa domieszkowano poliuretan solami LiClO4 lub LiCl, które wprowadzono za pomocą wytłaczarki dwuślimakowej. Otrzymane elektrolity poddano badaniom: wytrzymałościowym, twardości, spektroskopii FTIR oraz przewodnictwa...
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A review: Fabrication of porous polyurethane scaffolds
PublicationThe aim of tissue engineering is the fabrication of three-dimensional scaffolds that can be used for the reconstruction and regeneration of damaged or deformed tissues and organs. A wide variety of techniques have been developed to create either fibrous or porous scaffolds from polymers, metals, composite materials and ceramics. However, the most promising materials are biodegradable polymers due to their comprehensive mechanical...
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Nonlinear Viscoelastic Properties of Polyurethane Nanocomposites
PublicationIn recent years, the nonlinear viscoelastic behaviors of elastomeric nanocomposites have been examined, especially for a wide range of rubbery composite (including natural rubber) materials. This chapter describes the influence of fillers and nanofillers on the nonlinear viscoelastic properties of elastomeric polyurethane systems. These filled elastomers (similar to the classic natural rubber reinforced elastomers), also exhibit...
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Morphology and degradation of polyurehanes in different environments.
PublicationW pracy przedstawiono wyniki badań degradacji poli(estro-uretanów) (PEsUA i PEsUB) oraz poli(etero-uretano-mocznika)(PEtUU) w roztworach buforowych o zmiennym pH (168 godz., 70 oC), w środowisku trypsyny (37 oC, 1 m-c), Aspergillys niger (12 m-cy), kompoście z osadem czynnym (12 m-cy) i w wodzie morskiej (12 m-cy). Analizowano zmiany w morfologii i właściwościach fizykomechanicznych. Ustalono następujące sekwencje w zmianach zależności...
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The structure and conductivity of solid polyurethane electrolytes
PublicationPrzedmiotem badań były stałe elektrolity poliuretanowe otrzymane w wyniku syntezy MDI, PTMO, BD oraz TG z DMPA. Domieszkowanie LiCl zostało wykonane przy zastosowaniu przedłużacza. Badano przewodnictwo jonowe otrzymanych elektrolitów stałych przy użyciu technik stało i zmiennoprądowych. Przedstawiono również wyniki badań z wykorzystaniem technik mikroskopii elektronowej oraz FTIR-ATR.
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Clays as Inhibitors of Polyurethane Foams’ Flammability
PublicationPolyurethanes are a very important group of polymers with an extensive range of applications in different branches of industry. In the form of foams, they are mainly used in bedding, furniture, building, construction, and automotive sectors. Due to human safety reasons, these applications require an appropriate level of flame retardance, often required by various law regulations. Nevertheless, without the proper modifications,...
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Thermal and mechanical properties of polyurethanes modified with L-ascorbic acid
PublicationIn this study we report the thermal and mechanical properties of polyurethanes modified with ascorbic acid (AA). Ascorbic acid was used as a modifier at concentration of 1 or 2 mass%. The antioxidative properties of AA may improve the biocompatibility of the obtained materials, which were designed for biomedical applications. In this paper we describe characterization of obtained unmodified and ascorbic acid modified polyurethanes...
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Chemical structures and physical properties of cured segmental polyurethanes
PublicationPrzedmiotem badań były poliuretany (PUR) segmentowe otrzymywane w dwuetapowej syntezie oligomerycznego α,ω-dihydroksy(adypinianu etylenowo-butylenowego) oraz dwóch różnych aromatycznych diizocyjanianów: 4,4'-diizocyjanianu difenylenometanu (MDI) albo MDI modyfikowanego diizocyjanianem karbodiimidu. Na etapie przedłużania łańcucha, oprócz typowo używanego do tego celu 1,4-butanodiolu, stosowano triol - 1,3-dihydroksy-2-(hydroksymetyleno)propan...
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Wide range of properties of polyurethanes for medicine - characterization of biomaterials
PublicationW artykule opisano różnorodność poliuretanów stosowanych na polu biomedycznym. Wyrózniono mtody otrzymywania materiałów o róznych własciwościach, a tym samym zastosowaniach. Opisano 10 serii potrzymanych PU oraz wyniki charakterystyki fizycznej, powierzchniowej i biologicznej tych poliuretanów.
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Multiphase separated polyurethanes studied by micro Raman spectroscopy.
PublicationPrzedmiotem badań były poliuretany o zawartości 30% segmentów sztywnych,charakteryzujące się obecnością globul i sferolitów. Badania za pomocą mikro Ramana wykazały różny skład chemiczny w wymienionych mikroobszarach. W globulach stwierdzono zanik obecności segmentów giętkich lub ich bardzo znikomą ilość w porównaniu z matrycą i sferolitami.
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The properties of polyurethanes based on synthetic polyhydroxybutyrate for medical application
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Environmental impact and industrial development of biorenewable resources for polyurethanes
PublicationPolyurethanes 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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Automatic tuning of a resonant circuit in wireless power supply systems for biomedical sensors
PublicationIn this paper, a tuning method of a resonant circuit suited for wireless powering of miniature endoscopic capsules is presented and discussed. The method allows for an automatic tuning of the resonant frequency and matching impedance of a full wave rectifier loading the resonant circuit. Thereby, the receiver tunes so as to obtain the highest power efficiency under given conditions of transmission. A prototype receiver for wireless...
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Advanced OCT techniques for biomedical applications - theoretical ideas versus technical restriction
PublicationW pracy przedstawiono dyskusję nad możliwościami pomiarowymi współczesnych systemów OCT o różnych konfiguracjach ( w tym o konfiguracji Mach-Zehndera i Michelsona) pracujących w dziedzinie czasu lub częstotliwości. Przedstawiono między innymi konfiguracje czułe na stan polaryzacji, na ruch w wykonaniu światłowodowym lub objętościowym.
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Nanoparticles associated with antimicrobial peptides (AMPs) promising combination for biomedical and veterinary applications
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The Biocompatibility and Self-Healing Effect of a Biopolymer’s Coating on Zn Alloy for Biomedical Applications
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Brain-Inspired Deep Networks for Facial Expression Recognition. Frontiers in Biomedical Technologies
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Biomedical engineering of polysaccharide-based tissue adhesives: Recent advances and future direction
PublicationTissue adhesives have been widely used for preventing wound leaks, sever bleeding, as well as for enhancing drug delivery and biosensing. However, only a few among suggested platforms cover the circumstances required for high-adhesion strength and biocompatibility, without toxicity. Antibacterial properties, controllable degradation, encapsulation capacity, detectability by image-guided procedures and affordable price are also...
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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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Molecular dynamics studies of polyurethane nanocomposite hydrogels
PublicationPolyurethane 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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Study on the strength of laminated polyurethane-steel joints
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Thermal properties of polyamide 6/polyurethane blends
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rigid polyurethane foams modified with selected nanofillers
PublicationThe nanofillers: natural montmoryllonite (MMT) - Bentonite, natural MMT modified with a quaternary ammonium salt - Cloisite30B, has been used in rigid polyurethane foams (PUFs). The influence of fillers amounts on processing parameters, physical-mechanical properties (density, water absorption, brittleness and compression strength) and thermal properties (thermal stability, fire behaviours) of such foams has been analysed. The...
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Preparation and characterization of rigid polyurethane-polyglycerolnanocomposite foams
PublicationThis work reports on the preparation of polyurethane-polyisocyanurate (PUR-PIR) foams containing different polyglycerols and layered silicate nanoclays. The rigid polyurethane foams were obtained in a laboratory scale, in a single step method, from a two-component system with a NCO to OH groups ratio equal to two. The reaction mixture consisted of the proper amounts of a commercial oligoetherpolyol, polyglycerol, catalysts, water,...
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ASCORBIC ACID IN POLYURETHANE SYSTEMS FOR TISSUE ENGINEERING
PublicationThe introduction of the paper was devoted to the main items of tissue engineering (TE) and the way of porous structure obtaining as scaffolds. Furthermore, the significant role of the scaffold design in TE was described. It was shown, that properly designed polyurethanes (PURs) find application in TE due to the proper physicochemical, mechanical and biological properties. Then the use of L-ascorbic acid (L-AA) in PUR systems for...
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Elastic polyurethane foams containing graphene nanoplatelets
PublicationElastic polyurethane foams were produced from two-component polyurethane systems (SPECFLEX NE 113 izocyjanian/NR 816 poliol system—SPC and Elastic MBMarket company system POLYOL ET MB 500/ISO ET MB 800—ET) by using a one-step method. The foams were a graphene nanoplatelets (GNP) in the amount ranging from 1 to 2 wt.%. The effect of the nanofiller on polyurethane matrix was determined by analyzing the chemical structure, static...
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The Influence of PEG on Morphology of Polyurethane Tissue Scaffold
PublicationIn this study, polyurethanes (PU) were synthesized from oligomeric dihydroxy(etylene-butylene adipate), poly(ethylene glycol) (PEG), hexamethylene diisocyanate (HDI), 1,4-butanediol (BDO) as chain extender and stannous octoate as catalyst. PEG due to its hydrophilic character influences physical and chemical properties of PU. For testing were used PU having the following weigh contents of PEG: 0%, 7%, and 14%. Porous scaffolds...
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Polyurethane nanocomposites obtained with organically modified montmorillonites.
PublicationW pracy przedstawiono wyniki badań dotyczące analizy właściwości i struktury nanokompozytu montmorylonit/poliuretan. Przeprowadzono pomiary właściwości mechanicznych i badania strukturalne z wykorzystaniem dyfrakcji promieni rentgenowskich i transmisyjnej mikroskopii elektronowej.
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Recent theoretical and practical applications of micellar liquid chromatography (MLC) in pharmaceutical and biomedical analysis
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