Wyniki wyszukiwania - Biblioteka Nauki

1

Synthesis and physicochemical characterization of silicafillers modified with octakis({3-methacryloxypropyl}dimethylsiloxy) octasilsesquioxane

100%

Szwarc-Rzepka K. , Gogola N. , Siwińska-Stefańska1 K. , Marciniec B. , Jesionowski T.

Polish Journal of Chemical Technology

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2013

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tom 15

|

nr 4

15-23

EN

Hybrid nanofillers of silica grafted with octakis({3-methacryloxypropyl}dimethylsiloxy) octasilsesquioxane were obtained by the method based on solvent evaporation with the use of both hydrated or emulsion spherical silica. Octakis({3-methacryloxypropyl}dimethylsiloxy) octasilsesquioxane was applied as a modifying agent and it was synthesized by employing the hydrosilylation reaction. The effectiveness of modification of the hybrid nanofillers obtained was verified using Fourier transform infrared spectroscopy and nuclear magnetic resonance (29Si and 13C CP MAS NMR). The products obtained were characterized by determination of their physicochemical properties and porous structure, including specific surface area, pore diameter and pore volume. Dispersion degree and particle size of the nanofillers was characterized by NIBS (Non-Invasive Back-scatter) method and laser diffraction technique, while their morphology by transmission electron microscopy.

2

A novel conversion of inert carbon nanotubes to highly dispersed fibres

100%

Tang X. , Zhao Y. , Jiao Q. , Cao Y.

Materials Science Poland

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2010

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tom Vol. 28, No. 3

671--677

EN

Multiwalled carbon nanotubes were functionalized with alkyl groups and transformed to form highly dispersed carbon nanofibres (CNFs) in ethylenediamine via the Benkeser reaction. The functionalized CNFs were characterized by transmission electron microscopy, scanning electron microscopy, Raman, infrared spectroscopoy as well as thermogravimetric analysis. The functionalized CNFs with long alkyl chains can be highly dispersed in universal solvents such as ethanol, toluene and N, N-dimethyl- formamide. The conversion mechanism has been investigated and the electrophilic reagents were proposed as key factors affecting the conversion degree.

3

Modification of gold nanoparticle surfaces with pyrenedisulfide in ligand-protected exchange reactions

100%

Uznański P. , Kurjata J. , Bryszewska E.

Materials Science Poland

|

2009

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tom Vol. 27, No. 3

659--670

EN

We provide a study of ligand place-exchange reaction on Au nanoparticles. Nanoparticles of the dimensions of 7-9 nm were fabricated by high-temperature anhydrous route in the presence of primary aliphatic amine. The advantage of weak coordination to gold, through the nonbonding electrons of the amino group, was to use in an exchange of an initial protective ligand. Therefore, among other stabilizing agents, photoactive dialkyldisulfide molecules functionalized with fluorescent pyrene moieties were attached. The photophysical properties of such a stabilized gold system were investigated during placeexchange reaction. Fluorescence studies show that the excimeric band, characteristic of bispyrene, disappears in the spectrum after binding to the gold NPs, indicating that pyrene molecules are adsorbed separately on the surface. Efficient quenching of monomeric emission suggests that deactivation of the fluorescent excited state occurs through a radiationless transition, probably a charge transfer one, formed due to prior electron transfer from pyrene moiety to gold. Kinetics of chemisorption of pyrene disulfide and its desorption in the presence of thiols was also studied, revealing that both processes comprise a fast and a slow component with an overall rate higher for the desorption.

4

Synthesis and physicochemical characterization of silicafillers modified with octakis({3-methacryloxypropyl}dimethylsiloxy) octasilsesquioxane

100%

Szwarc-Rzepka K. , Gogola N. , Siwińska-Stefańska K. , Marciniec B. , Jesionowski T.

Polish Journal of Chemical Technology

|

2013

|

tom Vol. 15, nr 4

15-23

EN

Hybrid nanofillers of silica grafted with octakis({3-methacryloxypropyl}dimethylsiloxy) octasilsesquioxane were obtained by the method based on solvent evaporation with the use of both hydrated or emulsion spherical silica. Octakis({3-methacryloxypropyl}dimethylsiloxy) octasilsesquioxane was applied as a modifying agent and it was synthesized by employing the hydrosilylation reaction. The effectiveness of modification of the hybrid nanofillers obtained was verified using Fourier transform infrared spectroscopy and nuclear magnetic resonance (29Si and 13C CP MAS NMR). The products obtained were characterized by determination of their physicochemical properties and porous structure, including specific surface area, pore diameter and pore volume. Dispersion degree and particle size of the nanofillers was characterized by NIBS (Non-Invasive Back-scatter) method and laser diffraction technique, while their morphology by transmission electron microscopy.

5

Modification of PET surface properties using extremely non-equilibrium oxygen plasma

88%

Junkar I. , Modic M. , Mozeti M.

Open Chemistry

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2015

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tom 13

|

nr 1

EN

Polyethylene terephthalate (PET) foils have been exposed to oxygen plasma and its afterglow in order to reveal compositional and structural modifications of the surface layer. Oxygen plasma was created by electrode-less RF discharge in a glass chamber so the O-atom density was close to 1022 m-3 although the density of charged particles was only about 1 × 1016 m-3. Long-living reactive particles created in plasma were leaked into the afterglow chamber using a two-stage rotary pump of pumping speed 4.4 × 10-3 m3 s-1. The density of O-atoms in the afterglow as measured with a catalytic probe was 3 × 1021 m-3, while the density of reactive oxygen molecules was estimated theoretically. The functionalization was accomplished even after a brief exposure to either plasma or afterglow since all samples were saturated with oxygen-rich functional groups as revealed by XPS. The water contact angle measurements, however, showed that only plasma treatment allowed for super-hydrophilicity, explained by rich surface morphology as detected by AFM. The differences in morphological properties between plasma and afterglow treated samples were explained by different interaction mechanisms between low and high energy particles impinging the polymer surface.

6

Structural Changes in Fibrous Ballistic Materials During PACVD Modification

75%

Struszczyk M. H. , Urbaniak-Domagała W. , Puszkarz A. K. , Wilbik-Hałgas B. , Cichecka M. , Sztajnowski S. , Puchalski M. , Miklas M. , Krucińska I.

Fibres & Textiles in Eastern Europe

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2015

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tom Vol. 23, no. 6 (114)

102--115

EN

The modification of specialized textiles including ballistic textiles by an effective and ecological technique is the main objective for screening the optimal way to obtain multi-functionalised products. The aim of the research was to optimise the method of Plasma Assisted Chemical Vapour Deposition (PACVD) of ballistic textile: p-aramid fabrics and fibrous materials made of ultra-high molecular weight polyethylene to produce a functionalized surface supported by the various kinds of deposited polymers. The research was carried out to screen the several processing parameters of PACVD with the presence of low-molecular mass organic compounds containing fluoro- or silane moieties to obtain a change in the surface behaviour of ballistic textiles. The process of PACVD allowed to effectively steer the behaviour of the surface properties of modified ballistic textiles, such as the amount of the deposited polymer and its form as well as chemical characterisation depending on the processing parameters.

PL

Modyfikacja specjalistycznych tekstyliów balistycznych, w tym tkanin, dzięki zastosowaniu efektywnych i ekologicznych technik, stanowi główny cel selekcji optymalnych dróg uzyskania wielofunkcjonalnych produktów. Celem przeprowadzonych badań była optymalizacja plazmowej depozycji polimerów (Plasma Assisted Chemical Vapour Deposition - PACVD) na balistycznych materiałach włókienniczych: tkaninach p-aramidowych oraz włóknistych materiałach wykonanych z polietylenu o znacząco wysokiej masie cząsteczkowej (UHMWPE) do uzyskania sfunkcjonalizowanej powierzchni dzięki depozycji różnego typu polimerów. Badania przeprowadzono celem wykreowania zmian właściwości powierzchni balistycznych tekstyliów poprzez selekcję wielu parametrów procesowych PACVD w obecności niskocząsteczkowych związków organicznych zawierających fluor lub grupy silanowe. Proces PACVD umożliwił skuteczne sterowanie właściwościami powierzchni zmodyfikowanych tekstyliów balistycznych, poprzez: ilość deponowanego polimeru i jego postać, a także charakterystykę chemiczną, zależnych od parametrów procesowych.

7

Controlled functionalization of sp2 carbon allotropes for the reinforcement of diene elastomers

75%

Barbera V. , Bernardi A. , Torrisi G. , Porta A. , Galimberti M.

Elastomery

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2017

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tom T. 21, nr 4

235--251

EN

This paper reports functionalization reactions of sp2 carbon allotropes, both nano- and nanostructured, able to introduce heteroatoms such as oxygen and nitrogen, without altering the bulk crystalline organization of the graphitic substrates. sp2 carbon allotropes were: carbon black (CB), nanosized graphite with high surface area (HSAG), multiwalled carbon nanotubes (CNT). Reactions of carbon allotropes were performed with either KOH or hydrogen peroxide or a serinol derivative, 2-(2,5-dimethyl-1H-pyrrol-1-yl)-1,3-propanediol (serinolpyrrole, SP), in the absence of solvents or catalysts, by simply donating either thermal or mechanical energy. Sulphur cured composites with HSAG containing hydroxy groups (from the reaction with KOH) revealed better mechanical properties than composites from melt blending with pristine HSAG. CB functionalized with SP was able to promote reduction of Payne effect in compounds based on CB and silica.

PL

W artykule przedstawiono reakcje funkcjonalizacji alotropów węgla sp sp2 , zarówno nano-, jak i nanostrukturalnych, zdolnych do wprowadzania heteroatomów, takich jak tlen i azot, bez zmiany struktury krystalicznej materiałów grafitowych. Alotropami węgla sp2 były: sadza (CB), grafit nanokrystaliczny o dużej powierzchni (HSAG), wielowarstwowe nanorurki węglowe (CNT). Reakcje alotropów węgla przeprowadzono za pomocą KOH lub nadtlenku wodoru lub pochodnej serinolu, 2-(2,5-dimetylo-1H-pirol-1-ylo)-1,3-propanodiolu (serinolopirolu, SP), w nieobecności rozpuszczalników lub katalizatorów, po prostu dostarczając energii cieplnej lub mechanicznej. Kompozyty utwardzane siarką z grupami hydroksylowymi HSAG (z reakcji z KOH) wykazały lepsze właściwości mechaniczne niż kompozyty uzyskane w wyniku mieszania w stanie stopionym z czystym HSAG. CB funkcjonalizowana za pomocą SP była w stanie zapewnić redukcję efektu Payne’a w mieszankach opartych na CB i krzemionce.

8

Badanie wpływu alkoholi na odpowiedź funkcjonalizowanych czujników impedancyjnych

75%

Chabowski K. , Pałetko P. , Nitsch K. , Piasecki T. , Grabiec P. , Janus P. , Gotszalk T.

Elektronika : konstrukcje, technologie, zastosowania

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2012

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tom Vol. 53, nr 6

53-55

PL

Przedstawiono wyniki badań funkcjonalizowanych chemicznie miniaturowych czujników impedancyjnych wykonanych w technologii krzemowej. Pomiary widm impedancyjnych i analiza elektrycznych modeli równoważnych sensorów zanurzonych w alkoholach wykazały występowanie relaksacji dielektrycznej w zakresie bardzo małych częstotliwości związanej z istnieniem dipolowych stanów energetycznych na powierzchni SiO₂/SAM/alkohol. Zaobserwowano korelację pomiędzy wartościami przenikalności elektrycznej alkoholi a pojemnością czujnika zmierzoną przy częstotliwości 1 MHz.

EN

The results of investigations of chemically functionalized miniaturized impedance sensors made on silicon were performed. Measurement of impedance spectra and analysis of the electrical equivalent circuit of sensors immersed in alcohols revealed the presence of dielectric relaxation in the range of very low frequencies. This relaxation was associated with the existence of dipole energy states on the surface of SiO₂/SAM/alcohol. There was a correlation between alcohol and the dielectric sensor capacitance measured at a frequency of 1 MHz.

9

Zróżnicowanie struktur organizacyjnych ze względu na układ pionów scalonych na przykładzie przedsiębiorstw hutniczych

75%

Miśkiewicz R.

Hutnik, Wiadomości Hutnicze

|

2012

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tom Vol. 79, nr 10

760--766

PL

W artykule przedstawiono znaczenie zróżnicowania struktur organizacyjnych przedsiębiorstw w procesie ich łączenia i integracji w ramach fuzji i przejęć na przykładzie grupy przedsiębiorstw przemysłu hutniczego. Zakresem badań objęto człony kierownicze przedsiębiorstw w ramach struktur organizacyjnych zwanych departamentyzacją. Ponieważ w tych typach struktur funkcjonalizacja występuje na drugim szczeblu zarządzania, przeprowadzono badania, pozwalające ustalić różnice występujące w strukturach poszczególnych pionów scalonych. Ustalone różnice odniesiono do struktury wzorcowej, co pozwoliło, w efekcie końcowym, do ustalenia miejsca poszczególnych działów w pionach scalonych przedsiębiorstw. Wyniki badań mogą posłużyć przedsiębiorstwom hutniczym do modernizacji struktur organizacyjnych w celu zapewnienia im lepszej realizacji funkcji.

EN

This paper presents the importance of differentiating the organizational structures of enterprises in the process of their joining and integration within the mergers and acquisitions, based on the examples of a group of steel industry enterprises. The scope of the research included senior business units within the organizational structures called departmentalization. As functionalization occurs on the second level of management in these types of structures, the research allowing to establish the differences in the structures of individual merged units was carried out. The established differences were related to the standard structure, which eventually allowed to determine the location of various departments in the units of merged enterprises. The results of the research can be used by steel companies to modernize organizational structures in order to ensure a better functions realization.

10

The gas response of hydroxyl modified SWCNTs and carboxyl modified SWCNTs to H2S and SO2

75%

Zhang X. , Yang B. , Dai Z. , Luo C.

Przegląd Elektrotechniczny

|

2012

|

tom R. 88, nr 7b

311--314

EN

H2S and SO2 are important characteristic gases reflecting latent insulated defects in gas insulated switchgear (GIS).The detection of the H2S and SO2 is of great significance to diagnose and assess the operating status of GIS. In this paper, the single-walled carbon nanotubes (SWCNTs) are modified by hydroxyl and carboxyl, respectively. The gas sensing response of the modified SWCNTs to H2S and SO2 are studied. The results show that the sensitivity of SWCNTs modified by carboxyl is higher than that of SWCNTs modified by hydroxyl to H2S, the same for SO2.

PL

Przedstawiono metodę detekcji H2S iSO2 jako możliwość oceny stanu izolacji przełączników gazowych GIS. Jako czujnik wykorzystano nanorurki węglowe SWCNTs modyfikowane przez wodorotlenki hydroxyl i carboxyl.

11

Enhancement of graphene quantum dots based applications via optimum physical chemistry: A review

75%

Jegannathan P. , Termeh Yousefi A. , Karim M. S. A. , Kadri N. A.

Biocybernetics and Biomedical Engineering

|

2018

|

tom Vol. 38, no. 3

481--497

EN

Graphene quantum dots (GQDs) is a promising new substance from the carbon material family that has been attracting researchers of many fields, such as biomedical sensors, medical imaging, polymer science, solar cells, light emitting diodes, and photoelectrons. Its unique electrical and mechanical properties could encourage its usage due to its low cost, high surface area, safety, stable luminescence, excellent biocompatibility, suitable conductivity, and low toxicity. The dispersibility of GQDs in common solvents depends on hydrophobicity/hydrophilicity, which is particularly important toward its homogeneous incorporation into various polymer layers. This review discusses the global demand for GQDs and explore the main factors encouraging its utilization in various devices. Moreover, different synthesis methods of GQDs were compared, and recent investigation on GQDs based composite applications are analyzed. Finally, the future of GQDs is detailed, focusing on the gaps in its role in future technology.

12

Halogenation of β-estradiol by a rationally designed mesoporous biocatalyst based on chloroperoxidase

75%

Salcedo K. , Torres-Ramírez E. , Haces I. , Ayala M.

Biocatalysis

|

2014

|

tom 1

|

nr 1

EN

Chloroperoxidase from Caldariomyces fumago was immobilized in Eupergit® C, a commercial mesoporous acrylic-based material. Due to low stability of the enzyme under neutral and basic pH, the usual covalent immobilization procedures cannot be applied to this enzyme. Several strategies were followed in order to achieve a stable interaction between the protein and the support. The support was efficiently functionalized with different reactive groups such as aromatic and aliphatic amines, glutaraldehyde, diazonium ions, and maleimide moieties; solvent-exposed amino acid residues in chloroperoxidase were identified or created through chemical modification, so that they were reactive under conditions where the enzyme is stable. Enzyme load and retained activity were monitored, obtaining biocatalysts with specific activity ranging from 200 to 25,000 U/g. The highest load and activity was obtained from the immobilization of a chemically-modified CPO preparation bearing a solvent-exposed free thiol group. This biocatalyst efficiently catalyzed the transformation of β-estradiol, an endocrine disruptor.

13

Functionalization methods of carbon fibers – an overview

75%

Magdziarz S. , Frączyk J. , Boguń M.

Polimery

|

2023

|

tom Vol. 68, nr 6

307--316

EN

This article is a literature review related to the methods of functionalization of carbon fibers for tissue engineering applications. Through physical modification, it is possible to obtain a layer of a chemical compound on the carbon fibers surface and to impart additional properties. On the other hand, chemical modification may lead to the incorporation of appropriate functional groups into the carbon fiber structure, capable of attaching, among others, biologically active compounds. The paper presents the advantages and disadvantages of the carbon fibers modifying methods, with particular emphasis on the use of such modified fibers in medicine.

PL

Niniejsza praca stanowi przegląd literatury dotyczący metod funkcjonalizacji włókien węglowych przeznaczonych do zastosowań w inżynierii tkankowej. Poprzez modyfikację fizyczną możliwe jest uzyskanie warstwy związku chemicznego na powierzchni włókien węglowych i nadanie im dodatkowych właściwości. Natomiast modyfikacja chemiczna może prowadzić do wbudowania w strukturę włókna węglowego odpowiednich grup funkcyjnych zdolnych do przyłączania m.in. związków aktywnych biologicznie. W pracy przedstawiono zalety i wady stosowanych metod modyfikacji włókien węglowych, ze szczególnym naciskiem na zastosowanie tak modyfikowanych włókien w medycynie.

14

Antibacterial Finishing of Cotton Fabrics

63%

Jantas R. , Górna K.

Fibres & Textiles in Eastern Europe

|

2006

|

tom Vol. 14, no. 1 (55)

88--91

EN

Antibacterial properties have been given to the surface of a cotton fabric by a two-stage process of chemical modification. First, the fabric was treated with chloroacetyl chloride in THF using pyridine as a catalyst to incorporate chloroacetate groups. During the second stage, the chloroacetylated cotton was reacted with a potassium salt of a bioactive 1-naphthylacetic acid to prepare a cellulose-1-naphthylacetic acid adduct. The results of the FTIR ATR spectra confirmed the existence of a chemical linkage between 1-naphtylacetic acid and the cellulose chains. As a result of this modification, the cotton fabric surface becomes hydrophobic, and the fabric thermal stability is decreased. The hydrolysis in the heterogenous phase of adducts showed that the release of the bioactive compound is dependent on the pH values of the medium. An analysis of the antibacterial activity of one of the obtained adducts towards Escherichia coli was also performed.

PL

W artykule przedstawiono dwuetapową chemiczną metodę modyfikacji tkaniny bawełnianej w celu nadania jej właściwości antybakteryjnych. W pierwszym etapie, funkcjonalizowaną grupami chlorooctanowymi powierzchnię tkaniny bawełnianej, otrzymano w wyniku jej reakcji z chlorkiem chloroacetylu używając pirydyny jako katalizatora i tetrahydrofuranu. W drugim etapie przyłączenie bioaktywnego kwasu naftylooctowego do grup chlorooctanowych przeprowadzono w wyniku ich reakcji z solą potasową tego kwasu. Widma FTIR ATR, potwierdzają istnienie chemicznego wiązania pomiędzy łańcuchem celulozy i bioaktywnym kwasem 1-naftylooctowym. Na podstawie wyników heterogenicznej alkalicznej hydrolizy wytworzonego na powierzchni tkaniny adduktu celuloza-1-naftylooctowy kwas stwierdzono, że szybkość uwalniania biocydu zależy od pH środowiska reakcji. Ilościowe testy aktywności bakteriologicznej modyfikowanej adduktem tkaniny, wykazały zarówno bakteriostatyczną jak i bakteriobójczą aktywność do Escherichia coli.

15

Funkcjonalizacja chemiczna nanorurrek węglowych

63%

Bystrzejewski M. , Pichler T.

Wiadomości Chemiczne

|

2006

|

tom [Z] 60, 9-10

569-607

EN

The discovery of carbon nanotubes (CNTs) and the recognition of their exceptional properties have generated a great deal of interest. The possible applications arise from the remarkable properties of CNTs such as the highest Young's modulus, highest thermal conductivity, ballistic electron transport, and field emission resulting from high aspect ratio. The functionalization of carbon nanotubes has become a very actively discussed topic because the CNTs modification is believed to open the road towards real nanotechnology applications. This review with 266 references describes the results on covalent and noncovalent chemical functionalization of carbon nanotubes and related nanostructures. Physical and chemical properties as well as possible applications of functionalized CNTs are also presented.

16

Mesoporous alumina as a biomaterial for biomedical applications

63%

Xifre-Perez E. , Ferre-Borull J. , Pallares J. , Marsal L. F.

Mesoporous Biomaterials

|

2015

|

tom 2

|

nr 1

EN

Porous anodic alumina (PAA) is a biomaterial based on a cost-effective electrochemical anodization of pure aluminum with unique geometrical properties, i.e., self-ordering hexagonal pore distribution, tunable pore diameters and interpore distances, and uniformity of the pores in the vertical direction (nanochannels). These remarkable properties have found important applications in several fields such as energy storage, optics, photonics, magnetism, catalysis and, in particular, in the biomedicine field. In this work, we review the current state of research and key issues on cell culture and implants, drug delivery systems with complex release profiles and specific action, and high efficiency and sensitivity biosensors with different biosensing mechanisms, all of them based on PAA. The biocompatibility, morphology of the surface, nanoestructural engineering in-depth, surface functionalization and coatings are discussed and analyzed in detail.

17

Funkcionalizaciâ v rasplave polimerov i sopolimerov olefinov: osobennosti struktury i svojstv, oblasti primeneniâ

63%

Krivoguz J. M. , Makarenko O. A. , Jurkovski B. , Peseckij S. S.

Zeszyty Naukowe Politechniki Poznańskiej. Budowa Maszyn i Zarządzanie Produkcją

|

2010

|

tom Nr 12

197-204

EN

Characteristic features are described for the melt functionalization process (grafting of vinyl monomers containing functional polar groups) as applied to different polymers and co-polymers of olefins, as well as blended system based on them. Fields for practical use of the functionalized products are suggested.

18

Polimery funkcjonalne jako unikalne materiały stosowane w selektywnej adsorpcji

63%

Nazim T. , Cegłowski M.

Wiadomości Chemiczne

|

2022

|

tom [Z] 76, 7-8

509--527

EN

Functional polymers are increasingly being used as materials with a range of unique properties. Due to their structure and relatively high flexibility in a synthetic context, they are becoming highly relevant in a variety of applications. One of the numerous examples of the use of functional polymers is water treatment. Using the adsorption phenomenon, it is possible to remove or reduce the amount of harmful organic compounds and heavy metal ions in the water. This review provides information on both the synthesis methods and characterization of functional polymers in terms of their adsorption properties. Among others, this paper presents the results of research on functional polymers carried out by Professor Schroeder's research group. The research was mainly focused on the selective adsorption of dyes and heavy metal ions, which are significant water pollutants. The overall results show that the adsorption of the synthesized polymer materials is high influenced by parameters such as pH, temperature, contact time of the adsorbent with the adsorbate and the initial adsorbate concentration. In the case of the adsorption phenomenon, the Langmuir or Freundlich isotherm turned out to be the most appropriate model for the tested materials, while in the case of kinetic models, the highest R2 coefficient was usually obtained using the pseudo-second-order equation.

19

Graphite Nanosheet Exfoliation From Graphite Flakes Through Functionalization Using Phthalic Acid

63%

Kim J. H. , Lee J. H.

Archives of Metallurgy and Materials

|

2015

|

tom Vol. 60, iss. 2B

1251--1255

EN

In order to fabricate graphite nanosheets from graphite flakes, edge-functionalized graphite nanosheets were prepared by a functionalization method using phthalic acid as the molecule to be grafted. A polyphosphoric acid/P2O5 solution containing graphite and phthalic acid were heated at different temperatures for 72 h in a nitrogen atmosphere. It was confirmed by transmission electron microscopy and atomic force microscopy that the resultant phthalic acid-functionalized graphite nanosheets had a large surface area of 20.69 μm2 in average and an average thickness of 1.39 nm. It was also found by X-ray diffractometry and Fourier transform infrared spectroscopy (FT-IR) analysis that the functionalization caused the formation of C=O bonds at the edges of the graphite nanosheets. The yield from this functionalization method was found to be dependent on the reaction temperature, only when it is between 70 and 130°C, because of the dehydration of phthalic acid at higher temperatures. This was confirmed by FT-IR analysis and the observation of low thermal energies at low temperatures.

20

Chemical activation of polymer microfiltration membranes by surface engineering

63%

Skowroński J. , Kacprzyńska-Gołacka J.

Problemy Eksploatacji

|

2016

|

tom no. 2

163--172

EN

This paper presents the results of a chemical activation of polymer membranes obtained by plasma treatment. Plasma activation may be considered a final functionalization or as an intermediate step for chemical modification. Materials threated with argon plasma under different process conditions become less hydrophobic as a result of oxygen introduction into the activated chemical structure of polypropylene. The surface of activated polymer containing chemically bound oxygen is more reactive and susceptible for further functionalization, increasing the variety of potential applications.

PL

W artykule przedstawiono rezultaty prac eksperymentalnych nad plazmową obróbką polipropylenu ukierunkowaną na jego właściwą modyfikację lub wstępną aktywację w procesach funkcjonalizacji membran polimerowych. Zastosowanie plazmy pozwala kształtować cechy materiałów w sposób szybki, ekonomiczny i przyjazny środowisku, a wprowadzone zmiany mają wysoki potencjał aplikacyjny. W rezultacie obróbki polipropylenu plazmą argonową wywołano wzrost hydrofilowości powierzchni pierwotnie apolarnego polimeru, będący efektem wzrostu udziału powierzchniowych grup tlenoorganicznych. Dzięki temu zwiększa się ogólna reaktywność chemiczna materiału i tym samym zakres możliwości dalszych modyfikacji. Prowadzone procesy obróbki nie spowodowały radykalnych zmian w obrazach mikroskopowych badanych obiektów, co pozwala przypuszczać, że nie uległy pogorszeniu ich pierwotne cechy aplikacyjne.