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1

Fabrication of Silver-Impregnated Silica Aerogel Composite for Energy Applications

Kapadnis Pratik S., Kim Kyungsun, Park Hyung-Ho, Hwang Haejin

Archives of Metallurgy and Materials

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2024

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Vol. 69, iss. 1

77--80

EN

In this study, Ag-impregnated silica aerogel composites were fabricated via wet impregnation. In this approach, silver salt was reduced with ethylene glycol in the presence of polyvinylpyrrolidone (PVP) at reaction temperature 80°C. PVP was used as a capping agent to protect the Ag nanoparticles (NPs) from agglomeration. Wet impregnation was used to synthesize the Ag/SiO2 composite by combining the reduction of AgNO3 with a silica aerogel slurry. Experimental results showed that the AgNO3 concentration and PVP: AgNO3 ratio had an active influence on the growth of Ag NPs on silica surfaces. The X-ray diffraction (XRD) patterns of the composite material showed no imprints of impurities or parasitic materials except for Ag and SiO2. Scanning electron microscopy (SEM) images revealed that the Ag NPs were well impregnated into the porous silica aerogel structure. It was found that SiO2 aerogel surfaces were homogeneously surrounded by the Ag NPs.

2

Preparation of Electrospun Composite PEG/PVP Phase-Change Nanofibers and their Application in Cigarette Cooling Filters

Chen Chen, Li Liqun, Qiao Yuemei, Guo Chunsheng, Ye Yajun, Du He

Fibres & Textiles in Eastern Europe

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2023

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Vol. 31, no. 3

9-13

EN

Composite phase-change nanofibers were prepared by electrospinning with polyethylene glycol (PEG) as the phase-change material (PCM) and polyvinylpyrrolidone (PVP) as the carrier matrix. The high PEG content endowed the nanofibers with an excellent cooling effect and significantly reduced the smoke temperature. For PEG70/PVP nanofibers, the smoke temperature can be decreased 45℃ at the 8th puff, and be kept below 45℃. The cooling test proved that the electrospun PEG/PVP phase-change nanofibers exhibited a desirable cooling performance, improving the comfort of cigarette products. And the composite PEG/PVP phase-change nanofibers present great potential as the cooling cigarette filter material for HnB tobacco application.

3

Gamma-induced grafting of rice straw cellulose with polyvinylpyrrolidone

Suhartini Meri, Tachrim Zetryana Puteri, Anggarini Niken Hayudanti, Rahmawati Rahmawati, Prasetyani Amanda, Melawati June, Deswita, Sugeng Bambang

Polimery

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2022

|

Vol. 67, nr 9

450--456

EN

Cellulose obtained from rice straw was grafted with polyvinylpyrrolidone (Cell-g-PVP). The process was induced by gamma simultaneous irradiation (Co-60). The presence of the grafted PVP chains was confirmed by FT-IR, XRD and EDS methods. The influence of the irradiation dose (20 and 30 kGy) on the reaction efficiency and thermal stability of Cell-g-PVP was investigated. The grafting yield at the dose of 30 kGy was about 56%. The higher dose of radiation resulted in better thermal stability. The AAS results showed that Ni(II), Cu(II), and Cr(II) ions can be adsorbed by Cell-g-PVP. The order of ion metals adsorption capacity of Cell-g-PVP was Cu(II) > Ni(II) > Cr(II). The adsorption isotherm of Cu(II) metal ion using the Cell-g-PVP followed the Langmuir adsorption isotherm whereas the chemical adsorption and the adsorption energy were constant on all sides of the copolymer.

PL

Celulozę otrzymaną ze słomy ryżowej poddano szczepieniu poliwinylopirolidonem (Cell-g-PVP). Proces indukowano promieniowaniem gamma (Co-60). Obecność zaszczepionych łańcuchów PVP potwierdzono metodami FT-IR, XRD i EDS. Zbadano wpływ wielkości dawki promieniowania (20 i 30 kGy) na wydajność reakcji istabilność termiczną Cell-g-PVP. Stopień zaszczepienia przy dawce 30 kGy wynosił ok. 56%. Większa dawka promieniowania skutkowała większą stabilnością termiczną. Metodą AAS oceniono właściwości adsorpcyjne Cell-g-PVP względem jonów Ni(II), Cu(II) i Cr(II). Zdolność do adsorpcji zmniejszała się w szeregu Cu(II) > Ni(II) > Cr(II). Izoterma adsorpcji jonów Cu(II) miała przebieg zgodny z izotermą adsorpcji Langmuira.

4

Prediction of the Properties of Modified Phenol-Formaldehyde Composites Using Mathematical Modeling of the Composition of the Polymer Mixture

Krasinskyi Volodymyr, Jachowicz Tomasz, Malinowski Rafał, Bajer Krzysztof, Dulebova Ludmila

Advances in Science and Technology. Research Journal

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2022

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Vol. 16, no. 4

138--146

EN

The paper presents the results of studies of adhesive strength under shearing, thermal stability, and the content of the gel fraction of adhesive materials and enamels based on modified phenol-formaldehyde resins. Epoxy resin and polyvinylpyrrolidone were used to modify the phenol-formaldehyde resin. The influence of the content of components in the phenol-formaldehyde composition and the curing conditions on the properties of the obtained adhesive materials and coatings is analyzed. The effect of polyvinylpyrrolidone on internal stresses in adhesive joints has been established. By mathematical planning, the isolines of the characteristics of composite materials based on modified phenol-formaldehyde resin depending on their component’s compositions are plotted, and the regression coefficients are found, enabling one to get materials with predicted properties. From a technical and economic point of view, the following content of additives in modified phenol-formaldehyde resin is most optimal: epoxy resin from 25 to 50 wt%, polyvinylpyrrolidone from 0.5 to 1.0 wt%, curing catalyst from 1 to 2.5 wt%.

5

Nanogels obtained by gamma radiation induced polymerization

Shafie Nur Fathin Amirah, Hamzah Mohd Yusof, Ali Roshafima Rasit

Polimery

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2021

|

T. 66, nr 9

451--458

EN

The influence of 2-(dimethylamino)ethyl methacrylate (DMAEMA) concentration on the temperature sensitivity of nanogels based on N-isopropylacrylamide (NIPAAM), poly(vinylpyrrolidone) (PVP), poly(ethylene glycol) diacrylate (PEGDA) by gamma radiation induced polymerization was investigated. Dynamic light scattering (DLS) and zeta potential measurements were used to characterize the nanogels. Temperature has been found to cause the nanogel particles to swell and shirnkage, allowing controlled dosing of the drug contained in capsules. The developed nanogels are promising materials with great potential for biomedical applications.

PL

Zbadano wpływ stężenia metakrylanu 2-(dimetyloamino)etylu (DMAEMA) na wrażli - wość na temperaturę nanożeli otrzymanych na bazie N -izopropyloakrylamidu (NIPAAM), poli(winylo - pirolidonu) (PVP), diakrylanu poli(glikolu etylenowego) (PEGDA) metodą polimeryzacji indukowanej promieniowaniem gamma. Do scharakteryzowania nanożeli stosowano pomiary dynamicznego roz - praszania światła (DLS) i potencjału Zeta. Wykazano wpływ temperatury na pęcznienie i kurczenie się cząstek nanożelu, co umożliwia kontrolowane dozowanie leku zawartego w kapsułkach. Opracowane nanożele są obiecującymi materiałami o dużym potencjale do zastosowań biomedycznych.

6

The Manufacturing of Composite Materials in the Matrix of Modified Phenol-Formaldehyde Resins

Krasinskyi Volodymyr, Jachowicz Tomasz, Dulebova Ludmila, Gajdoš Ivan, Malinowski Rafał

Advances in Science and Technology. Research Journal

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2021

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Vol. 15, no. 4

267--272

EN

The work develops the method of obtaining new composite materials based on novolac phenol-formaldehyde resin with improved adhesion properties and heat resistance. The composites were obtained by chemical modification of phenol-formaldehyde resin by epoxy resin and polyvinylpyrrolidone during the hardening of the composition. The mechanism of resins modification and hardening has been determined. It is shown that due to the modification, the heat resistance and adhesive strength of the obtained enamels and coatings have significantly increased. In particular, with the polyvinylpyrrolidone content from 0.5 to 1 wt% and epoxy resin from 25 to 50 wt%, the adhesive strength of the compositions increases 5-7 times.

7

Nanocomposites Based on Polyamide and Montmorillonite Obtained from a Solution

Krasinskyi Volodymyr, Suberlyak Oleh, Kochubei Viktoria, Jachowicz Tomasz, Dulebova Ludmila, Zemke Viktoria

Advances in Science and Technology. Research Journal

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2020

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Vol. 14, no. 3

192--198

EN

This work deals with the development of a method for obtaining polyamide and montmorillonite based nanocomposite, which was modified with polyvinylpyrrolidone by mixing in a formic acid solution. The structure and thermophysical properties of the obtained nanocomposites were investigated by means of the X-ray, differentialthermal, thermogravimetric and IR spectroscopic analyses. It was found that nanomodified polycaproamide has a higher crystallinity and higher thermal stability than the original PA-6, and is characterized by considerably higher melt fluidity. The presence of polyvinylpyrrolidone and exfoliated montmorillonite in the nanocomposite structure was confirmed experimentally.

8

The Effect of the Formation of Polymer/Surfactant Complexes on Selected Tribological Properties of Their Aqueous Solutions

Sułek M. W., Jedynak R.

Tribologia

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2018

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nr 5

117--122

EN

Aqueous solutions of sodium alkyl sulphate (surfactant) and polyvinylpyrrolidone (polymer) whose physicochemical properties, including complexing ability, have been widely described in the literature were proposed as a model lubricant. It has been assumed that aqueous solutions of these compounds will favourably modify lubricating properties of water under high load conditions. For this purpose, measurements were made on a four-ball apparatus (T-02 Tester) for aqueous solutions of these compounds. Two kinds of tests were carried out: at constant loads (2, 3, and 4 kN) and variable loads within the range of 0 to 7.2 kN. Unexpectedly, high decreases in motion resistance and wear as well as an increase in antiseizure properties were found in relation to water as a base. The results obtained are so promising that solutions with an optimized composition can find practical applications. The surprisingly high effectiveness of the additives used results from the formation of surfactant/polymer complexes. These adducts adsorb at the interface, and, under friction conditions, they form a lubricant film capable of carrying high loads.

PL

Jako modelową substancję smarową zaproponowano wodne roztwory alkilosiarczanu sodu (surfaktant) i poliwinylopirolidonu (polimer), których właściwości fizykochemiczne, w tym zdolność do kompleksowania, zostały szeroko opisane w literaturze. Postawiono tezę, że wodne roztwory tych związków będą korzystnie modyfikowały właściwości smarne wody w warunkach wysokich obciążeń. W tym celu dla wodnych roztworów tych związków wykonano pomiary na aparacie czterokulowym (Tester T-02). Przeprowadzono 2 rodzaje testów: przy stałych obciążeniach (2, 3, 4 kN) oraz przy zmiennym obciążeniu w przedziale zmienności od 0 do 7,2 kN. Stwierdzono nieoczekiwanie duże obniżenie oporów ruchu i zużycia oraz wzrost właściwości przeciwzatarciowych w odniesieniu do wody jako bazy. Uzyskane wyniki są na tyle obiecujące, że roztwory o zoptymalizowanym składzie mogą znaleźć zastosowanie praktyczne. Niespodziewanie wysoka efektywność stosowanych dodatków jest konsekwencją tworzenia kompleksów surfaktanta z polimerem. Addukty te adsorbują na granicy faz, a w warunkach tarcia tworzą film smarny zdolny do przenoszenia wysokich obciążeń.

9

Effect of small additives of polyamide modified by polyvinylpyrrolidone and montmorillonite on polypropylene technological properties and heat resistance

Krasinskyi Volodymyr, Suberlyak Oleh, Kochubei Viktoria, Klym Yurii, Zemke Viktoria, Jachowicz Tomasz

Advances in Science and Technology. Research Journal

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2018

|

Vol. 12, no. 2

83--88

EN

The effect of small polyamide additives modified with polyvinylpyrrolidone and montmorillonite on polypropylene technological properties and heat resistance has been researched in the work. It has been determined that the melt flow index of the obtained composites increases by more than 2 times in comparing with pure PP. It has been shown that adding a small amount of polyamide modified by montmorillonite-polyvinylprolidone mixture to polypropylene significantly increases heat resistance of the material. The displacement of the beginning of thermal-oxidation destruction and burning samples into the range of higher temperatures on 114-123oC, dependently on the modified polyamide content has been observed.

10

Effect of PVP and Polybond Compatibilizers on Dynamic Properties of Polymer Blends Analyzed with DMTA

Gnatowski Adam, Sosnowski Marcin

Advances in Science and Technology. Research Journal

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2018

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Vol. 12, no. 1

36--40

EN

The properties of the polymer blends depend significantly on the type of the components. That kind of influence is manifested especially in the change of physical properties. The crucial condition for reaching the homogeneity and the properties of a polymer material is its mutual miscibility. Additional agents that make mixing easier are usually applied. They have reactive effect which results in a chemical modification of output polymer along with the change in its chemical structure and the structure of macrochains. In order to achieve this within the confines of the carried research, the polyvinylpyrrolidone (PVP) and polybond has been used. Some results concerning mechanical properties of polypropylene (PP) and polyamide (PA) blends with the addition of PVP and polybond are presented in the paper. In case of mixing PP with PVP, the hydrophobic interactions occur in the created macromolecules with the participation of the hydrocarbon chains. In case of mixing PA with PVP, the PVP solution in PA is created, with strong intermolecular interactions, including the hydrogen ones. The intermolecular interactions occur and they differently influence parameters of the modified materials in the blends on the basis of such polymers. Therefore the aim of the research was to evaluate the influence of the compatibilizers such as PVP and Polybond 3150 on the dynamic properties of PP/PA blends. The analysis of dynamic proprieties of polymer blends was performed with the Dynamic Mechanical Thermal Analysis (DMTA). The mixing of polymers in different proportions with compatibilizers (PVP, Polybond 3150) results in materials of completely different properties in comparison to the base materials. Detailed results concerning response to sinusoidal load in function of temperature and frequency are presented in the paper.

11

PVP based materials: Biodegradation in different environments

Vanharova L., Julinova M., Slavik R.

Ecological Chemistry and Engineering. S

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2017

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Vol. 24, nr 2

299--309

EN

The research deals with biodegradation of films prepared from polyvinylpyrrolidone and polylactic acid (PVP/PLA). Biodegradation of PVP/PLA films was supported by the following additives: 1-methyl-2-pyrrolidone, 1-octyl-2-pyrrolidone, acrylamide and N-acetyl-L-phenylalanine according to the previous study. The films were prepared by a solvent casting technique. Biodegradation was observed using the respirometric method in different environments. The films subjected to biodegradation were analyzed by scanning electron microscopy and Fourier transform infrared spectroscopy. It was found that the films are substantially degraded, but not in the biological way; PVP was quickly removed in presence of water because of its easy solubility. In contrast, this fact could support biodegradation of PLA, which becomes more available for microorganisms when PVP leaves PLA matrix.

12

Nanocząstki magnetytu powlekane polimerami do zastosowań biomedycznych. Cz. II. Nanocząstki Fe3O4 z powłokami z polimerów syntetycznych

Chełminiak D., Ziegler-Borowska M., Kaczmarek H.

Polimery

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2015

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T. 60, nr 2

87--94

PL

Artykuł jest drugą częścią przeglądu literatury dotyczącej nanocząstek magnetytu stosowanych w biologii i medycynie. Omówiono układy nanocząstek Fe3O4 z powłokami z polimerów syntetycznych, m.in. z poliwinylopirolidonu, poli(glikolu etylenowego), polidopaminy. Przedstawiono przykłady trójskładnikowych układów magnetytu ze związkami krzemu, stabilizowanych polimerami.

EN

This article is a second part of literature review concerning magnetite nanoparticles used in biology and medicine. Fe3O4 nanoparticles coated by synthetic polymers such as polyvinylpyrrolidone, poly(ethylene glycol) and polydopamine are described. Examples of trilayer hybrids composed of magnetite, silicon compound and polymer are also presented. Particular attention is paid to biological and medical applications of polymers containing magnetic nanoparticles as contrast agents for magnetic resonance imaging, drug delivery systems, compounds used in separation techniques and in hyperthermic anticancer therapy.

13

Development of a Polymeric Composition for Antimicrobial Finish of Cotton Fabrics

Burkitbay A, Raimovna Taussarova B, Zhumatayevna Kutzhanova A, Maratovna Rakhimova S

Fibres & Textiles in Eastern Europe

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2014

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Vol. 22, no. 2 (104)

96--101

EN

This article considers the development of a new polymeric composition on the basis of polyvinyl pyrrolidone, silver ion solution and benzoic acid for the antimicrobial finishing of cotton fabrics. The advantages of the application of a new composition on the basis of polyvinyl pyrrolidone, silver ion solution and benzoic acid include the availability of the material’s use, as well as the simplicity of the technological process: finishing may be performed with any tenter drier aggregated with a padding machine and combining the drying process and thermal treatment. The newly developed efficient composite formulation for biocidal finishing of cotton fabrics is comparatively inexpensive, environmentally safe, and resistant to wet treatment. Its application offers opportunities of manufacturing of a wide range of competitive, environmentally compatible, and biologically stable cellulose textiles with various textures and various fabric weights. As a result of the study it has been found out that cotton fabrics finished with the composition on the basis of polyvinyl pyrrolidone, silver ion solution and benzoic acid have advanced antimicrobial characteristics preventing fouling with mould fungi and are not deteriorated by microorganisms under operational conditions.

PL

W artykule rozważono opracowanie nowej polimerowej kompozycji opartej na poliwinylo pyrolidonie, roztworze jonów srebra i kwasie benzoesowym w celu uzyskania antymikrobowej preparacji tkanin bawełnianych. Korzyścią zastosowania nowej preparacji jest dostępność składników kompozycji jak i prostota technologicznego procesu nanoszenia za pomocą ogólnie dostępnych urządzeń laboratoryjnych. Opracowana preparacja jest stosunkowo tania, nie stwarza niebezpieczeństwa dla środowiska i jest odporna na mokrą obróbkę. Zastosowanie oferuje możliwości produkcji szerokiego spektrum biologicznie stabilnych, przyjaznych środowisku materiałów celulozowych o różnej strukturze i różnych masach powierzchniowych, impregnowane tkaniny nie ulegają deterioracji przez mikroorganizmy w warunkach normalnego użytkowania.

14

Initiating biodegradation of polyvinylpyrrolidone in an aqueous aerobic environment: technical note

Julinova M., Kupec J., Slavik R., Vaskova M.

Ecological Chemistry and Engineering. S

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2013

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Vol. 20, nr 1

199-208

EN

A synthetic polymer, polyvinylpyrrolidone (PVP - E 1201) primarily finds applications in the pharmaceutical and food industries due to its resistance and zero toxicity to organisms. After ingestion, the substance passes through the organism unchanged. Consequently, it enters the systems of municipal wastewater treatment plants (WWTP) without decomposing biologically during the waste treatment process, nor does it attach (through sorption) to particles of activated sludge to any significant extent, therefore, it passes through the system of a WWTP, which may cause the substance to accumulate in the natural environment. For this reason the paper investigates the potential to initiate aerobic biodegradation of PVP in the presence of activated sludge from a municipal wastewater treatment plant. The following agents were selected as the initiators of the biodegradation process - co-substrates: acrylamide, N-acethylphenylalanine and 1-methyl-2-pyrrolidone, a substance with a similar structure to PVP monomer. The biodegradability of PVP in the presence of co-substrates was evaluated on the basis of biological oxygen demand (BOD) as determined via a MicroOxymax O2/CO2/CH4 respirometer. The total substrate concentration in the suspension equaled 400 mgźdm-3, with the ratio between PVP and the cosubstrate being 1:1, while the concentration of the dry activated sludge was 500 mgźdm-3. Even though there was no occurrence of a significant increase in the biodegradation of PVP alone in the presence of a co-substrate, acrylamide appeared to be the most effective type of co-substrate. Nevertheless, a recorded decrease in the slope of biodegradation curves over time may indicate that a process of primary decomposition was underway, which involves the production of metabolites that inhibit activated sludge microorganisms. The resulting products are not identified at this stage of experimentation.

PL

Syntetyczny polimer, poliwinylopirolidon (PVP - E 1201), znajduje zastosowanie przede wszystkim w przemyśle farmaceutycznym i spożywczym ze względu na jego odporność i brak toksyczności dla organizmów. Po spożyciu substancja ta przechodzi przez organizm niezmieniona. W związku z tym, że w procesie przetwarzania odpadów w komunalnym systemie oczyszczalni ścieków (OŚ) polimer ten nie ulega rozkładowi biologicznemu ani nie jest znacząco sorbowany w osadzie czynnym, może on gromadzić się w środowisku naturalnym. Ze względu na istnienie tych problemów w artykule przedstawiono możliwości aerobowej inicjacji biodegradacji PVP w obecności osadu czynnego miejskiej oczyszczalni ścieków. Jako inicjatory procesu biodegradacji zostały wybrane następujące środki: kosubstraty, akryloamid, N-acetylofenyloalanina i 1-metylo-2-pirolidon, substancje o strukturze podobnej do monomeru PVP. Biodegradację PVP w obecności kosubstratów oceniano na podstawie biologicznego zapotrzebowania na tlen (BOD), określonego za pomocą respirometru MicroOxymax O2/CO2/CH4. Całkowite stężenie substratu w zawiesinie wynosiło 400 mg ź dm-3 dla stosunku PVP i kosubstratu wynoszącego 1:1 oraz dla stężenia suchego osadu czynnego wynoszącego 500 mg ź dm-3. Chociaż nawet w tym układzie nie stwierdzono wzrostu biodegradacji samego PVP w obecności kosubstratu, to sam akryloamid okazał się najbardziej efektywnym rodzajem podłoża. Niemniej jednak, zauważony spadek nachylenia krzywych biodegradacji w czasie może wskazywać, że zachodzi proces rozkładu pierwotnego, który wiąże się z produkcją metabolitów hamujących aktywowane mikroorganizmy osadu. trzymane produkty nie zostały zidentyfikowane na tym etapie badań.

15

Initiating biodegradation of polyvinylpyrrolidone in an aqueous aerobic environment

Julinová M., Kupec J., Slavík R., Vaskova M.

Proceedings of ECOpole

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2012

|

Vol. 6, No. 1

121--127

EN

A synthetic polymer, Polyvinylpyrrolidone (PVP - E 1201) primarily finds applications in the pharmaceutical and food industries due to its resistance and zero toxicity to organisms. After ingestion, the substance passes through the organism unchanged. Consequently, it enters the systems of municipal wastewater treatment plants (WWTP) without decomposing biologically during the waste treatment process, nor does it attach (through sorption) to particles of activated sludge to any significant extent, therefore, it passes through the system of a WWTP, which may cause the substance to accumulate in the natural environment. For this reason the paper investigates the potential to initiate aerobic biodegradation of PVP in the presence of activated sludge from a municipal wastewater treatment plant. The following agents were selected as the initiators of the biodegradation process - co-substrates: acrylamide, N-acethylphenylalanine and 1-methyl-2-pyrrolidone, a substance with a similar structure to PVP monomer. The biodegradability of PVP in the presence of co-substrates was evaluated on the basis of biological oxygen demand (BOD) as determined via a MicroOxymax O2/CO2/CH4 respirometer. The total substrate concentration in the suspension equaled 400 mg·dm–3, with the ratio between PVP and the co-substrate being 1:1, while the concentration of the dry activated sludge was 500 mg·dm–3. Even though there was no occurrence of a significant increase in the biodegradation of PVP alone in the presence of a co-substrate, acrylamide appeared to be the most effective type of co-substrate. Nevertheless, a recorded decrease in the slope of biodegradation curves over time may indicate that a process of primary decomposition was underway, which involves the production of metabolites that inhibit activated sludge microorganisms. The resulting products are not identified at this stage of experimentation.

16

Hydrogel coatings for artificial heart implants

Trzaskowski M., Butruk B., Ciach T.

Challenges of Modern Technology

|

2011

|

Vol. 2, no. 1

19--22

EN

Polyurethanes (PU) are nowadays one of the most widely used types of polymers for biomedical applications. The segmented nature of these materials enables to obtain both flexibility and mechanical strength within the same material. However, there is a need to modify a surface of PU in order to produce highly hemocompatible materials that can be used in fabrication of permanent blood-contacting devices such as vascular implants, valves or hearts. Among many types of modifications, hydrogel coating appears to be very promising. Such modification increases the hydrophilicity of PU which in turn causes an increase in the bio- and hemocompatibility of the material. The aim of presented study was to create a polyvinylpyrrolidone (PVP) hydrogel coating onto a surface of polyurethane. A possibility of using a free radical polymerization reaction was investigated. The obtained materials were analyzed in terms of durability, swelling ratio and contact angle. The FTIR-ATR analysis confirmed that polyurethane surfaces have been successfully coated with PVP.

17

Influence of the coating process parameters on the quality of PUR/PVP hydrogel coatings for PVC medical devices

Paradowska A., Kaźmierska K., Ciach T.

Polish Journal of Chemical Technology

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2010

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Vol. 12, nr 2

38-45

EN

To decrease friction factor and enhance the biocompatibility of medical devices manufactured from poly(vinyl chloride), PVC, the surface modification with wear resistant polyurethane/polyvinylpyrrolidone (PUR/PVP) hydrogel coating can be applied. In the present work substrates were dip-coated with PVP and PUR solutions and thermally cured. The variable process parameters were: solvent system; concentration of polymers (1, 2 or 3% w/v); coating baths temperature (22, 38 and 55°C); drying temperature (32, 50 and 67°C); length of break between process steps (5, 30 and 90 s); and solutions storage time (up to 72 hrs). The quality of coatings was determined by friction coefficients against porcine aorta, weights of the deposited layer and the swelling capacity. The solvent system and polymers concentration were crucial factors. The increased temperature of coating solutions caused increased deposition but decreased durability. The most lubricious samples were dried in 50oC. Coatings from the solutions prepared 24h prior to use had better properties than those from fresh solutions.

18

Effect of ionic strength of the solution of some hydrogen — bonded interpolymer complexes on the stability and thermodynamic parameters

Ahmadi M. H., Rajabi F. H., Gholehzadeh A.

Polimery

|

2009

|

T. 54, nr 4

261-265

EN

The effect of ionic strength of the solution on the complex formation of poly(acrylic acid) (PAA) with poly(vinyl pyrrolidone) (PVP) has been studied in aqueous solutions containing various inorganic salts (NaCl, KCl, NH4Cl). Stability constant (Ks), degree of linkage (...) and related thermodynamic parameters (..., ... and ...) have been compared for different complexation systems. The comparative study indicated considerable difference in the values of these parameters, which has been explained on the basis of relative strength of H-bond present in different systems.

PL

Scharakteryzowano wpływ siły jonowej roztworu na proces komleksowania w układzie poli(kwas akrylowy)/poli(winylopirolidon); badania prowadzono w roztworach wodnych zawierających różne sole nieorganiczne (NaCl, KCl, NH4Cl). Określano stałą stabilności (Ks, rys. 1), stopień związania (?, tabela 2) oraz podstawowe parametry termodynamiczne (?G0, ?H0 and ?S0, rys. 2 i 3, tabela 3) omawianych układów ulegających skompleksowaniu. Wyniki wskazują na istotne różnice wartości wspomnianych parametrów w zależności od względnej siły wiązań wodorowych występujących w rozpatrywanych roztworach a także od oddziaływań hydrofobowych. Doświadczalną podstawę badań stanowiły pomiary pH (tabela 1).

19

Formation and properties of hydrogel membranes based on cross-linked copolymers of methacrylates and water-soluble polymers

Suberlyak O., Melnyk J., Skorokhoda V.

Engineering of Biomaterials

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2009

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Vol. 12, no. 86

5-8

EN

Experimental results concerning the effect of composition, nature of polymeric matrix, monomer and solvent on the structure, physico-mechanical and selective-transport characteristics of hydrogel membranes based on cross-linked grafted copolymers of methacrylates and water-soluble polymers (polyvinyl-pyrrolidone, polyvinyl alcohol) have been presented. Methods of high-penetrating hydrogel membranes formation have been developed and capability of directional control of their structure and operational characteristics has been determined.

20

Effect of magnetic field on the structure formation and properties of hydroxyethylmethacrylate / polyvinylpyrrolidone copolymers

Suberlyak O., Skorokhoda V.

Engineering of Biomaterials

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2009

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Vol. 12, no. 86

2-4

EN

The effect of a permanent magnetic field on the polymerization kinetics and structural parameters of a hydrogel network on the basis of 2-hydroxyethylmethacrylate with polyvinylpyrrolidone compositions has been investigated. It has been shown that the magnetic field activates matrix polymerization of mentioned compositions and assists in the structure formation of copolymers with a smaller crosslink density. The efficiency of the developed polymeric materials for production of ultrathin contact lenses "Glipox" has been confirmed.