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Wyniki wyszukiwania dla: polyesters
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DEGRADATION OF GFRP MARINE LAMINATES WITH NANO PARTICLE MODIFIED COATINGS
PublikacjaWater absorption and surface blistering behaviour was studied for polyester-matrix laminates with SiO2 nanoparticle reinforced gel coats. Accelerated water immersion tests at 37°C showed that addition of 10% nanoparticles increases blisters incubation time by ca. 50% compared to 5% and 0% nanoparticles composites.
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Self-Organization of Graft Copolymers and Retortable iPP-Based Nanoporous Films Thereof
PublikacjaPolyolefins might become inexpensive alternatives to the existing membranes based on polyethersulfone. Here we disclose the production of retortable, well-defined PP-based nanoporous membranes derived from amphiphilic graft copolymer precursors. The graft copolymers, containing a polypropylene backbone and polyester grafts, were obtained by grafting lactones, specifically δ-valerolactone and ε-caprolactone, from well-defined randomly...
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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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Structure analysis and thermal degradation characteristics of bio-based poly(propylene succinate)s obtained by using different catalyst amounts
PublikacjaLinear bio-based polyester polyols were prepared with the use of succinic acid and 1.3-propanediol (both with natural origin). As a catalyst was used tetraisopropyl orthotitanate (TPT). In order to determine the effect of various catalyst content on the thermal degradation characteristics, three different TPT amounts, as a 1.3-propanediol equivalent, were used, namely 0.1 mass% (PPS-0.1), 0.2 mass% (PPS-0.2) and 0.25 mass% (PPS-0.25)....
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Effect of bio-based components on the chemical structure, thermal stability and mechanical properties of green thermoplastic polyurethane elastomers
PublikacjaIt seems to be obvious that conditions changes during polyols synthesis have impact on the polyols properties. Even the chemical formula is the same or similar, physicochemical properties and also molecular weight of polyols might be different and are significant in term of future polyurethanes properties and processing. In this work, fully bio-based poly(propylene succinate)s synthesized at different temperature conditions were...
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Influence of thermal effects on mechanical properties of PVDF-coated fabric
PublikacjaThis paper describes the method of laboratory tests necessary for identification of temperature influence on mechanical properties of polyvinylidene fluoride-coated polyester fabric often used for tensile structures. Two nonlinear model descriptions are investigated. The first one is based on the piece-wise linear relations between stress and strain and the second one on the Murnaghan model of solid behavior. This paper is proposed...
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Mechanical properties of Precontraint 1202 S2 based on uniaxial tensile and creep tests
PublikacjaThe purpose of the paper is the estimation of the polyvinyl chloride – polyester-coated fabric (Precontraint 1202 S2) mechanical properties under uniaxial tensile tests as well as short- and long-time creep tests. The uniaxial tests are the basis of non-linear elastic description while the creep tests are used for the evaluation of the stiffness parameters in time and for the identification of the standard viscoelastic model. The...
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Degradation of polyurethanes in Compost Under Natural Conditions
PublikacjaThe 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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Phase separation in poly(butylene terephthalate)-based materials prepared by solid-state modification
PublikacjaThe morphology of a series of poly(butylene terephthalate) (PBT)/fatty acid dimer diol (FADD)-based copolyesters prepared by solid-state modi fi cation (SSM) was studied. It was shown that in copolyesters containing less than 10 wt% FADD two different phases, i.e. a PBT crystalline phase and a PBT-rich amorphous phase, are present. The FADD residues were more or less homogeneously distributed throughout the interlamellar regions....
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Modelling of the viscoelastic properties of the technical fabric VALMEX
PublikacjaThe analysis of the Burgers model used for the constitutive description of the technical fabric VALMEX vis-coelastic behavior is presented. It has revealed that the correctness of the identification depends strongly on the level of the immediate strain taken for calculations. Moreover, it has been proven that the Burgers model can be used for modelling of the viscoelastic properties of the polyester reinforced PVC coated VALMEX...
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Mechanical properties for preliminary design of structures made from PVC coated fabric
PublikacjaIn this paper, laboratory tests necessary for the identification of non-linear elastic immediate properties of the PVC coated polyester fabric (like AF 9032) are described. The material parameters are specified on the basis of the uniaxial tensile tests in the warp and weft directions as well as on the base of the biaxial tensile tests. For the identification process techniques based on the least squares method are used. The authors...
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Mechanical properties of mosquito nets in the context of hernia repair
PublikacjaThe paper deals with issue of applying mosquito nets as implants in hernia repair, which have already been used in resource-poor developing countries. Uniaxial tensile tests have been conducted on polyester mosquito meshes in two orthogonal directions. Non-linear elastic constitutive laws parameters have been identified to be applied in dense net material models. Mechanical performance of tested mosquito nets has been compared...
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Mechanical properties of Precontraint 1202S coated fabric under biaxial tensile test with different load ratios
PublikacjaThe paper describes a method of laboratory tests necessary for identifying the mechanical properties of polyester coated fabrics named Precontraint 1202S with PVDF surface treatment. Two sets of initial material parameters for dense net model and orthotropic model are specified. Material parameters for Precontraint 1202S coated fabric are specified on the basis of the biaxial tensile tests for different load ratios. In order to...
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Structure versus hydrolytic and thermal stability of bio-based thermoplastic polyurethane elastomers composed of hard and soft building blocks with high content of green carbon
PublikacjaNowadays, sustainability plays a key role in the design and synthesis of new materials. One of the methods for the preparation of green materials is incorporation into their structure the monomers with a high content of green carbon. Therefore, the aim of this work was to investigate the influence of the type and molecular mass of two bio-based polyester polyols and bio-glycol on the properties of aliphatic partially bio-based...
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DETERMINATION OF THE HYDROXYL NUMBER OF GROUND TIRE RUBBER PARTICLES VIA MODIFIED TEST METHOD FOR ISOCYANATE GROUPS
PublikacjaNowadays, considering the environmental trends and law regulations associated with the circular economy, it is very important to seek for the methods of by-products and waste utilization. The example of such material, which requires the attention and recycling method is ground tire rubber generated during recycling of post-consumer car tires. It can be introduced into various polymer matrices as a filler, but to enhance its effectivity...
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Water sorption and blistering of GFRP laminates with varying structures
PublikacjaThe microstructures, water absorption as well as blistering was studied for bi- and tri- axial glass fibre vinyl ester and polyester -matrix laminates coated with gel coat layer and uncoated. The effect of manufacturing technique on water sorption characteristics was considered. It was found that water sorption characteristics of GFRP depend on manufacturing methods. The least water intake was found for specimens having perfect...
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Topological behavior mimicking ethylene–hexene copolymers using branched lactones and macrolactones
PublikacjaPolyolefins are of paramount importance in the world of polymers due to their technological and economic potential.1 However, their nonpolar character significantly restricts the compatibility and adhesion properties, which consequently limits their versatility. Moreover, an intensified demand for materials from renewable resources can also become a problematic venture for the current polyolefin industry.2 Although Braskem and...
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Thermal degradation kinetics of poly(propylene succinate) prepared with the use of natural origin monomers
PublikacjaLinear biobased polyester polyols were prepared with the use of succinic acid and 1,3-pro- panediol (both with natural origin). Tetraisopropyl orthotitanate (TPT) was used as a catalyst. In order to determine the effect of various synthesis temperature conditions on the thermal degradation kinet- ics, nine sequences of temperature conditions were used during two-step polycondensation reaction. Thermogravimetric analysis was conducted...
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Identification of Bodner-Partom model parameters for technical fabrics
PublikacjaThe thorough analysis of modeling technical fabrics behavior with the viscoplastic Bodner-Partom constitutive law is presented. The study has been focused on differences between the warp and weft direction of the material. To obtain the model’s parameters only the uniaxial tensile laboratory tests with three different, but constant strain rates are required. The parameters have been found for polyester fibers PVC coated fabrics:...
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Experimental and Numerical Study on Mechanical Characteristics of Aluminum/Glass Fiber Composite Laminates
PublikacjaThe fiber-metal composites made of aluminum sheets and glass fibers reinforced with a polyester resin as the matrix were studied. The composites were prepared by hand lay-up method. Some aspects of manufacturing affecting the composite behavior were considered. In particular, the influences of the arrangement of layers and their number on the mechanical and physical properties of composites with ten different compositions were...
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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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The Antibacterial and Antifungal Textile Properties Functionalized by Bimetallic Nanoparticles of Ag/Cu with Different Structures
PublikacjaWe reported a preparation and characterization of five kinds of impregnation solutions, containing Ag/Cu in the formof bimetallic nanoparticles (alloy and core-shell) as well as ionic species. The cotton-polyester textiles were successfully impregnated during the washing and ironing process by as-prepared solutions to have antibacterial and antifungal properties against to Escherichia coli, Staphylococcus aureus, and Candida albicans....
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COMPOSITE MATERIAL SELECTION FOR A PATIENT TRANSFER ASSIST DEVICE
PublikacjaLaminates - layered composites containing at least two elements (matrix and reinforcement) widely used in industry have also found their usage in medicine. Their main feature is the ability to modify the material in order to obtain the required properties. Depending on the needs, we can modify reinforcement, type of resin or the method of bonding substrates. Commonly used fibers are: carbon fiber, glass and aramid fibers; resins...
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Gelatin-Modified Polyurethanes for Soft Tissue Scaffold
PublikacjaRecently, 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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Badania porównawcze wpływu grubości ścianki powłoki o przekroju niekołowym, wykonanej z tworzywa GRP, w obiekcie gruntowo-powłokowym
PublikacjaW artykule przedstawiono badania porównawcze przepustów wykonanych z tworzywa GRP (Glass Reinforcement Poliester) zabudowanych w warunkach naturalnych i obciążanych układem sił symulujących obciążenia komunikacyjne zgodne z „Modelem Obciążenia 1” wg [7]. Analizowano dwie konstrukcje o identycznym przekroju poprzecznym (profil dzwonowy DN3000/2400), ale różnej grubości ścianki: standardowej 45 mm i zredukowanej 35 mm. Badania obejmowały...
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Problems with modelling the strength properties of sailing vessels rigging ropes
PublikacjaThis article presents the basic parameters of soft ropes: natural fibre ropes, soft wire ropes and synthetic fibre ropes used for running rigging. There are only several materials still used for the production of natural fibre ropes, including cotton, jute, hemp, sisal and manila hemp. The most commonly used soft wire ropes are twisted pair ropes; for smaller diameters there is a 6x19M - FC rope and for larger diameters – 6x37M...
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Water absorption and blistering of glass fibre-reinforced polymer marine laminates with nanoparticle-modified coatings
PublikacjaMacro and microstructural damage was studied in typical glass fibre-reinforced polymer laminates with two types of coating systems – (a) isophtalic gel coat: pure or mixed with SiO2 nanoparticles 5 wt% (5%N) or 10 wt% (10%N) and (b) a two-layer coating system: urethane-modified vinyl ester-based gel coat and additional polyester barrier coat layer. Accelerated tests were performed at 50C for 50 days for specimens with nanoparticle-modified...
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Sustainable Strategy for Algae Biomass Waste Management via Development of Novel Bio-Based Thermoplastic Polyurethane Elastomers Composites
PublikacjaThis work concerns the waste management method of algae biomass wastes (ABW). For this purpose, we prepared bio-based thermoplastic polyurethane elastomer (bio-TPU) composites. Algae biomass wastes are derived from algal oil extraction of Chlorella vulgaris and from biomass of Enteromorpha and Zostera marina. ABWs were used in the bio-TPUs composites as a filler in the quantity of 1, 5, 10, and 15 wt.%. The bio-based composites...
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Structural, mechanical and thermal behavior assessments of PCL/PHB blends reactively compatibilized with organic peroxides
PublikacjaThe efficiency of two commercially available organic peroxides, dicumyl peroxide (DCP) and di-(2-tert-butyl-peroxyisopropyl)-benzene (BIB), during reactive processing of poly (ε-caprolactone)/poly (3-hydroxybutyrate) (PCL/PHB) blends was investigated. The changes in chemical structure of PCL/PHB blends, as a function of organic peroxide type (DCP/BIB) and content (in range: 0–1.0 parts by weight - pbw), were characterized by Fourier...
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Preparation of Well-Compatibilized PP/PC Blends and Foams Thereof
PublikacjaThe performance of polypropylene-poly(ethylene brassylate) block and graft copolymers and a polypropylene-polycaprolactone graft copolymer as compatibilizers for polypropylene-rich polypropylene/bisphenol A polycarbonate (PP/PC, 80/20 wt/wt) blends was elucidated. The copolymers were synthesized either by metal-catalyzed ring-opening polymerization or transesterification of a presynthesized polyester, initiated by hydroxyl-functionalized...
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Shape memory thin films of Polyurethane: Does graphene content affect the recovery behavior of Polyurethane nanocomposites?
PublikacjaThin 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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Assessing ecotoxicity and the endocrine potential of selected phthalates, BADGE and BFDGE derivatives in relation to environmentally detectable levels
PublikacjaThere is no doubt that the subject area of plasticmaterials (e.g., production of epoxy resins or polyesters) is inherently connected to issues concerning bisphenol A (BPA) and its analogues. Unfortunately, much less attention has been given to other compounds, which are also used for the production of these materials. Bisphenol A diglycidyl ether (BADGE) is a synthetic industrial compound obtained by a condensation reaction between...
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Characterization and Filtration Efficiency of Sustainable PLA Fibers Obtained via a Hybrid 3D-Printed/Electrospinning Technique
PublikacjaThe enormous world demand for personal protective equipment to face the current SARS-CoV-2 epidemic has revealed two main weaknesses. On one hand, centralized production led to an initial shortage of respirators; on the other hand, the world demand for single-use equipment has had a direct and inevitable effect on the environment. Polylactide (PLA) is a biodegradable, biocompatible, and renewable thermoplastic polyester, mainly...
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Kinetics study of the fully bio-based poly(propylene succinate) synthesis. Functional group approach
PublikacjaCurrently, the increasing importance of the bio-based chemical compounds development is visible in the polymer chemistry, chemical engineering and materials science. It is well-known that the various purity level and different contaminants characterize petrochemical-based compounds compared to their biobased counterparts. Therefore, it is necessary to find out the contaminants impact on the bio-based monomers synthesis. One of...
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Wastewater treatment by means of Advanced Oxidation Processes at basic pH conditions: A review
PublikacjaAdvanced oxidation processes (AOPs) have been used as an alternative and effective option for treatment of industrial wastewater, especially in the case of the non-biodegradable compounds. Despite of several well developed AOPs, the majority of them are effective only at acidic or neutral pH, namely Fenton related processes, making the list of available effective advanced oxidation technologies strongly limited. In many cases,...
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Bioactive polyurethanes applied as a surgical implants
PublikacjaSynthetic 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...