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Search results for: BADGE AND BFDGE DERIVATIVES
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Teloxantron inhibits the processivity of telomerase with preferential DNA damage on telomeres
PublicationTelomerase reactivation is one of the hallmarks of cancer, which plays an important role in cellular immortalization and the development and progression of the tumor. Chemical telomerase inhibitors have been shown to trigger replicative senescence and apoptotic cell death both in vitro and in vivo. Due to its upregulation in various cancers, telomerase is considered a potential target in cancer therapy. In this study, we identified...
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Calix[4]arenes appended with thioamide moieties as powerful tool for heavy metals recognition
PublicationSelectivity of new thioamide derivatives was assessed using those ligands as sensor materials in ion-selective membrane electrodes and tested towards Pb2+ - selectivity. The influence of the nature of the thioamide function (linear, branched or cyclic substituents) on their ionophoric properties was investigated. Electrodes based on cyclic thioamide moieties are promising analytical tools for monitoring Pb2+ concentration in natural...
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Convenient and efficient synthesis of functionalized unsymmetrical alkynyl sulfides
PublicationWe developed a simple and efficient method for the synthesis of functionalized unsymmetrical alkynyl sulfides under mild conditions in good yields. The designed method is based on the reaction of 5,5-dimethyl-2-thioxo-1,3,2-dioxaphosphorinan-2-disulfanyl derivatives with lithium acetylides. The developed method allows the preparation of unsymmetrical alkynyl sulfides bearing additional hydroxyl, carboxyl, or amino functionalities.
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Impact of dyes isomerization effect on the charge transfer phenomenon occurring on the dye/nanosemiconductor interface
PublicationThe present work aimed to find the answer how does the isomerization of the Ru based dyes affect the overall photon-to-current efficiency of the DSSCs and to explain the charge transfer phenomenon occurring on the dye/ nanosemiconductor interface. Therefore, electronic and optical properties of three bipyridine derivatives anchored on the TiO2 electrode were investigated by computational simulations based on quantum chemistry codes...
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Enhanced Toxicity of Bisphenols Together with UV Filters in Water: Identification of Synergy and Antagonism in Three-Component Mixtures
PublicationContaminants of emerging concern (CEC) localize in the biome in variable combinations of complex mixtures that are often environmentally persistent, bioaccumulate and biomagnify, prompting a need for extensive monitoring. Many cosmetics include UV filters that are listed as CECs, such as benzophenone derivatives (oxybenzone, OXYB), cinnamates (2-ethylhexyl 4-methoxycinnamate, EMC) and camphor derivatives (4-methylbenzylidene-camphor,...
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Peptide modification with thiomalonoamide moiety
PublicationAbstract: Meldrum acid derivatives under the thermal decomposition are well known source of ketenes. Recently we investigated chemical properties of thiocarbamolyl meldrum acids. We found that 5-(α-alkylamino- α'-sulfhydryl)methylene Meldrum's acids hated in the presence of amines produce thiomalonamides. We used this reaction to the one pot synthesis of series of short peptides containing thiomalonoamide motif.
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Synthesis and Cholinesterase Inhibitory Activity of N-Phosphorylated /N-Tiophosphorylated Tacrine
PublicationNovel phosphorus and thiophosphorus tacrine derivatives were designed, synthesized and their biological activity and molecular modeling was investigated as a new potential anti-Alzheimer's disease (AD) agents. All new synthesized compound exhibited lower toxicity against neuroblastoma cell line (SH-SY5Y) in comparison with tacrine. Two analogues in the series, 7 and 9, demonstrated lack of cytotoxicity against hepatocellular cells...
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SYNTHESIS OF PHOSPHORUS TACRINE ANALOGUES AS A NEW POTENTIAL ANTI-ALZHEIMER’S DISEASE AGENTS
PublicationA series of novel phosphorus tacrine derivatives was obtained in three steps, including synthesis of 9-chlorotacrine, connection of 9-chlorotacrine with hexamethylenediamine, 1,8-diaminooctane and 1,12-diaminododecane linkers and reaction of obtained tacrine diamine analogues with corresponding acid ester to give nine tacrine organophosphorus compounds. All of the obtained final structures were characterized by 1H NMR, 13C NMR,...
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A new 1-nitro-9-aminoacridine derivative targeting yeast topoisomerase II able to overcome fluconazole-resistance
PublicationFungal resistance remains a significant threat and a leading cause of death worldwide. Thus, overcoming microbial infections have again become a serious clinical problem. Although acridine derivatives are widely analyzed as anticancer agents, only a few reports have demonstrated their antifungal activity. In an effort to develop biologically active antifungals, twelve novel C-857 (9-(2′ -hydroxyethylamino)-1-nitroacridine) and...
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Novel Functionalization of Boron-Doped Diamond by Microwave Pulsed-Plasma Polymerized Allylamine Film
PublicationWe report the novel modification of a hydrogen-terminated polycrystalline boron-doped electrode with a microwave pulsed-plasma polymerized allylamine. Boron-doped diamond (BDD) was coated with a very thin layer of adherent cross-linked, pinhole- and additive-free allylamine plasma polymer (PPAAm) resistant to hydrolysis and delamination and characterized by a high density of positively charged amino groups. The pulsed microwave...
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‘Acridines’ as New Horizons in Antifungal Treatment
PublicationFrequent fungal infections in immunocompromised patients and mortality due to invasive mycosis are important clinical problems. Opportunistic pathogenic Candida species remain one of the leading causes of systemic mycosis worldwide. The repertoire of antifungal chemotherapeutic agents is very limited. Although new antifungal drugs such as lanosterol 14α-demethylase and β-glucan synthase inhibitors have been introduced into clinical...
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A convenient method for the preparation of functionalized N-acylsulfenamides from primary amides.
PublicationWe have developed a convenient method for the synthesis of functionalized N-acylsulfenamides under mild conditions and in moderate to good yields. The designed method is based on the reaction of (5,5-dimethyl-2-thioxo-1,3,2-dioxaphosphorinan-2-yl)-disulfanyl derivatives with nitrogen nucleophiles generated from primary amides or imides and sodium hydride. The developed method allows for the preparation of N-acylsulfenamides bearing...
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Access to Side-On Bonded Tungsten Phosphanylphosphinidene Complexes
PublicationMetathesis reactions between diimido complexes of tungsten(VI)[(ArN)2WCl2] (Ar = 2,6-iPr2C6H3) and lithium derivatives of diphosphanes R2P-P(SiMe3)Li (R = tBu and iPr) yield two anionic diimido complexes of tungsten with side-on bonded phosphanylphosphinidene ligands, [(ArN)2WCl(η2-R2P-P)]-. Both complexes are structurally characterized. A possible reaction mechanism and the role of donor solvents are discussed on the basis of...
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Escherichia coli K-12 suppressor-free mutants lacking early glycosyltransferases and late acyltransferases. Minimal lipopolysaccharide structure and induction of envelope stress response.
PublicationTo elucidate the minimal lipopolysaccharide (LPS) structure needed for the viability of Escherichia coli, suppressor-free strains lacking either the 3-deoxy-d-manno-oct-2-ulosonic acid transferase waaA gene or derivatives of the heptosyltransferase I waaC deletion with lack of one or all late acyltransferases (lpxL/M/P) and/or various outer membrane biogenesis factors were constructed. Δ(waaC lpxL lpxM lpxP) and waaA mutants exhibited...
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On existence and uniqueness of weak solutions for linear pantographic beam lattices models
PublicationIn this paper, we discuss well-posedness of the boundary-value problems arising in some “gradientincomplete” strain-gradient elasticity models, which appear in the study of homogenized models for a large class ofmetamaterials whosemicrostructures can be regarded as beam lattices constrained with internal pivots. We use the attribute “gradient-incomplete” strain-gradient elasticity for a model in which the considered strain energy...
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Chalcogen bonding interactions in a series of aromatic selenocyanates
PublicationSelenium atoms in aromatic selenocyanates are characterized by the occurrence of two σ-holes, a stronger one in the prolongation of the NC–Se bond and a weaker one in the prolongation of the Ar–Se bond. The crystal structures of several bis(selenocyanato) derivatives, prepared by a method originally developed for ortho bis-substituted derivatives, illustrate very well this difference, with a short NC–Se⋯NC ChB interaction organizing...
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Advanced oxidation processes for the removal of mono and polycyclic aromatic hydrocarbons – A review
PublicationAromatic hydrocarbons (AHs) are toxic environmental contaminants presented in most of the environmental matrices. Advanced oxidation processes (AOPs) for the removal of AHs in the account of complete mineralization from various environmental matrices have been reviewed in this paper. An in-depth discussion on various AOPs for mono (BTEX) and polyaromatic hydrocarbons (PAHs) and their derivatives is presented. Most of the AOPs were...
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Chemical Aspects of Biological Activity of Isothiocyanates and Indoles, the Products of Glucosinolate Decomposition
PublicationThere is growing evidence that cancer chemoprevention employing natural, bioactive compounds may halt or at least slow down the different stages of carcinogenesis. A particularly advantageous effect is attributed to derivatives of sulfur-organic phytochemicals, such as glucosinolates (GLs) synthesized mainly in Brassicaceae plant family. GLs are hydrolysed enzymatically to bioactive isothiocyanates (ITC) and indoles, which exhibit strong...
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Simple Fractal Calculus from Fractal Arithmetic
PublicationNon-Newtonian calculus that starts with elementary non-Diophantine arithmetic operations of a Burgin type is applicable to all fractals whose cardinality is continuum. The resulting definitions of derivatives and integrals are simpler from what one finds in the more traditional literature of the subject, and they often work in the cases where the standard methods fail. As an illustration, we perform a Fourier transform of a real-valued...
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EFFECT OF CHITOSAN-BASED SPRAYING ON THE QUALITY OF HIGHBUSH BLUEBERRIES (SUNRISE CULTIVAR)
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THE EFFECTS OF APPLYING CHITOSAN OF DIFFERENT MOLECULAR WEIGHTS ON THE GROWTH AND QUALITY OF KAMCHATKA BERRIES (LONICERA CAERULEA L.): PART 1
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THE EFFECT OF DIFFERENT MOLECULAR WEIGHTS OF CHITOSAN ON THE YIELD, QUALITY, AND HEALTH-PROMOTING PROPERTIES OF STRAWBERRIES
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EFFECT OF CHITOSAN AND META-TOPOLIN IN MICROPROPAGATION OF VACCINIUM CORYMBOSUM
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THE EFFECTS OF APPLYING CHITOSAN OF DIFFERENT MOLECULAR WEIGHTS ON THE QUALITY OF KAMCHATKA BERRIES (LONICERA CAERULEA L.): PART 2
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CHITOSAN AND META-TOPOLIN SUPPLEMENTATION OF THE MULTIPLICATION MEDIA OF VITIS VINIFERA L.
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CHARACTERISATION OF CHITOSAN/HYALURONIC ACID BLEND FILMS MODIFIED BY COLLAGEN
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INFLUENCE OF THE INTERMOLECULAR INTERACTION ON PHYSICO-CHEMICAL PROPERTIES OF CHITOSAN/HYALURONIC ACID BLENDS
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THE INFLUENCE OF THE TYPE SOLVENT ON THE STRUCTURE OF CHITOSAN BLENDS WITH HYALURONIC ACID
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EFFECT OF CHITOSAN AND LIPID LAYERS DEPOSITED ONTO POLYETHYLENE TEREPHTHALATE (PET) ON ITS WETTING PROPERTIES
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WETTABILITY OF HYBRID CHITOSAN/PHOSPHOLIPID COATINGS
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WETTABILITY OF CHITOSAN-MODIFIED AND LIPID/POLYPEPTIDE-COATED PEEK SURFACES
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SURFACE CHARACTERISTICS OF DPPC MONOLAYERS DEPOSITED FROM TITANIUM DIOXIDE–CHITOSAN–HYALURONIC ACID SUBPHASES ON A GLASS SUPPORT
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CHARACTERIZATION OF MIXED LANGMUIR MONOLAYERS OF CYCLOSPORINE A WITH THE PHOSPHOLIPID DPPC AT THE CHITOSAN SUBPHASE
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BEHAVIOUR OF TiO2/CHITOSAN DISPERSION AS A FUNCTION OF SOLUTION pH
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Molecular dynamics simulations of the affinity of chitin and chitosan for collagen: the effect of pH and the presence of sodium and calcium cations
PublicationChitosan and chitin are promising biopolymers used in many areas including biomedical applications, such as tissue engineering and viscosupplementation. Chitosan shares similar properties with hyaluronan, a natural component of synovial fluid, making it a good candidate for joint disease treatment. The structural and energetic consequences of intermolecular interactions are crucial for understanding the biolubrication phenomenon...
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REVIEW OF CURRENT RESEARCH ON CHITOSAN AS A RAW MATERIAL IN THREE-DIMENSIONAL PRINTING TECHNOLOGY IN BIOMEDICAL APPLICATIONS
PublicationThree-dimensional (3D) biomaterial manufacturing strategies show an extraordinary driving force for the development of innovative solutions in the biomedical sector, including drug delivery systems, disease modelling and tissue and organ engineering. Due to its remarkable and promising biological and structural properties, chitosan has been widely studied for decades in several potential applications in the biomedical field. However,...
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An efficient and convenient synthesis of unsymmetrical disulfides from thioacetates
PublicationWe have developed convenient methods for the synthesis of functionalized unsymmetrical dialkyl disulfides under mild conditions in very good yields. The designed method is based on the reaction of (5,5-dimethyl-2-thioxo-1,3,2-dioxaphosphorinan-2-yl)-disulfanyl derivatives 1 with functionalized alkyl thiolate anions, generated in situ from thioacetates2and sodium methoxide or butylamine. The developed method allows the preparation...
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Novel and Efficient Synthesis of Unsymmetrical Trisulfides
PublicationWe have developed a convenient method for the synthesis of unsymmetrical trisulfides under mild conditions in very good yields. The designed method is based on the straightforward preparation of 1-[(5,5-dimethyl-2-thioxo-1,3,2-dioxaphosphorinan-2-yl)trisulfanyl]dodecane from readily available 5,5-dimethyl-2-sulfanyl-2-thioxo-1,3,2-dioxaphosphorinane, sulfur dichloride (SCl2) and dodecane-1-thiol. The unsymmetrical trisulfides can...
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Inhibition of impurities formation in the synthesis of N-alkyltheobromines stimulated by microwave irradiation. Cationic and anionic response of membrane electrodes
PublicationN-Alkyltheobromine (1-9) derivatives were obtained by reacting theobromine with appropriate alkyl halide under microwave irradiation at 100-150 W and by conventional synthesis. Formation of by-products of oxygen atom alkylation and 1-N-alkyltheobromine ring opening were considered. The presented compounds 1-5 have been studied as ion carriers in ion-selective membrane electrodes. Selectivity of these membranes was studied towards...
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Phosphate tricyclic coumarin analogs as steroid sulfatase inhibitors: synthesis and biological activity.
PublicationIn the present work, we report convenient methods for the synthesis and biological evaluation of phosphate tricyclic coumarin derivatives as potential steroid sulfatase inhibitors. The described synthesis includes the straightforward preparation of 7-hydroxy-2,3-dihydro-1H-cyclopenta[c]chromen-4-one, 3-hydroxy-7,8,9,10-tetrahydro-6H-benzo[c]chromen-6-one and 3-hydroxy-8,9,10,11-tetrahydro-7H-cyclohepta[c]chromen-6-one modified...
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Decomposition of halogenated nucleobases by surface plasmon resonance excitation of gold nanoparticles
PublicationHalogenated uracil derivatives are of great interest in modern cancer therapy, either as chemotherapeutics or radiosensitisers depending on their halogen atom. This work applies UV-Vis spectroscopy to study the radiation damage of uracil, 5-bromouracil and 5- uorouracil dissolved in water in the presence of gold nanoparticles upon irradiation with an Nd:YAG ns-pulsed laser operating at 532nm at dierent uences. Gold nanoparticles...
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Morphology, Mechanical and Thermal Properties of Thermoplastic Polyurethane Containing Reduced Graphene Oxide and Graphene Nanoplatelets
PublicationPolyurethane/graphene nanocomposites were synthesized using commercial thermoplastic polyurethane (TPU, Apilon 52DE55), and two types of graphene derivatives: graphene nanoplatelets (GNP) and reduced graphene oxide (RGO). Fourier Transformation Infrared Spectroscopy Fourier Transformation Infrared Spectroscopy (FTIR) spectroscopy, TEM, and SEM microscopy and XRD techniques were used to chemically and structurally characterize GNP...
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Cytotoxic and Antioxidant Activities of Benzohydroxamic Acid Analogues
Publication20 benzohydroxamic acid analogues were synthesized and evaluated for their in vitro cytotoxicities against mouse mammary tumor cells as well as antioxidant activities against DPPH radical and superoxide anion. It was found that benzothiohydroxamic acids exhibit greater cytotoxicities than benzohydroxamic acids and N-isopropyl derivatives are more active than N-methyl ones. On the other hand, benzothiohydroxamic acids show more...
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Acceleration waves in the nonlinear micromorphic continuum
PublicationWithin the framework of the nonlinear elastic theory of micromorphic continua we derive the conditions for propagation of acceleration waves. An acceleration wave, also called a wave of weak discontinuity of order two, can be treated as a propagating nonmaterial surface across which the second derivatives of the placement vector and micro-distortion tensor may undergo jump discontinuities. Here we obtain the acoustic tensor for...
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Tuftsin-Properties and Analogs
PublicationImmunomodulation is one of the significant therapeutic strategies. It includes both stimulation or suppression of the immune system by a variety of substances called immunomodulators, designed to regulate the immune response of the organism to infections of varying etiology. An example of such a substance is tuftsin (TKPA) 3 (Fig. (1)). Tuftsin is an endogenous immunomodulator of a wide spectrum of biological activity. Tetrapeptide...
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BODIPY‐Perylene Charge Transfer Compounds; Sensitizers for Triplet‐Triplet Annihilation Up‐conversion
PublicationBODIPY heterochromophores, asymmetrically substituted with perylene and/or iodine at the 2 and 6 positions were prepared and investigated as sensitizers for triplet-triplet annihilation up conversion (TTA-UC). Single-crystal X-ray crystallographic analyses show that the torsion angle between BODIPY and perylene units lie between 73.54 and 74.51, though they are not orthogonal. Both compounds show intense, charge transfer absorption...
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A versatile and convenient preparation of unsymmetrical diaryl disulfides
PublicationWe have developed a convenient method for the synthesis of unsymmetrical diaryl disulfides under mild conditions in excellent yields. The described method is based on the straightforward preparation of 5,5-dimethyl-2-thioxo-1,3,2-dioxaphosphorinane-2-sulfenyl bromide from readily available 5,5-dimethyl-2-thiolo-2-thioxo-1,3,2-dioxaphosphorinane or bis(5,5-dimethyl-2-thioxo-1,3,2-dioxaphosphorinan-2-yl) disulfide. The unsymmetrical...
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Synthesis and structure determination of 2,3-diaryl-9,9-dioxo-1H-9-thia-1,4,4a,7,10-pentaazaphenanthrene-2-ols
Publication3-Amino-1,1-dioxopyrido[4,3-e]-1,4,2-dithiazine has been synthesized and applied to the synthesis of 3-amino-2-(4-thioxo-1,4-dihydropyridin-3-ylsulfonyl)guanidine. The reaction of the aminoguanidine with the appropriate 1,2-diarylethane-1,2-diones afforded 2,3-diaryl-9,9-dioxo-1H-9-thia-1,4,4a,7,10-pentaazaphenanthrene-2-ol derivatives. The structure of these compounds, which represent a novel heterocyclic ring system, was confirmed...
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Convenient Synthesis of Functionalized Unsymmetrical Vinyl Disulfides and Their Inverse Electron-Demand Hetero-Diels-Alder Reaction
PublicationThe simple, convenient, and efficient methods for the preparation of unsymmetrical vinyl disulfides with additional functional groups under mild conditions with moderate to high yields were designed. The developed methods include the reaction of S-vinyl phosphorodithioate with thiotosylates or S-vinyl thiotosylate with thiols. The designed methods allow for the synthesis of unsymmetrical vinyl disulfides with additional functionalities...
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Investigation of polyurethane elastomer–steel joints using glass lacquer as an adhesive agent
PublicationThis 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...