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1

Properties and Structure of Cellulosic Membranes Obtained from Solutions in Ionic Liquids Coagulated in Primary Alcohols

Fryczkowska B., Kowalska M., Biniaś D., Ślusarczyk C., Janicki J., Sarna E., Wyszomirski M.

Autex Research Journal

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2018

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Vol. 18, no. 3

232--242

EN

This paper presents the results of studies on the preparation of cellulosic membranes, from a solution in 1-ethyl-3- methylimidazolium acetate (EMIMAc), using the phase inversion method. Initially, the membranes were obtained by coagulation of the polymer film in water and primary alcohols (methanol, ethanol, 1-propanol, 1-butanol, 1-pentanol), 1-hexanol, 1-octanol) resulting in membranes with significantly differing morphologies. Subsequently, composite membranes were produced, with the support layer being a membrane with the largest pores, and the skin layer a membrane with smaller pores. The resulting membranes were tested for physicochemical and transport properties. The morphology of the membrane surfaces and their cross-sections were investigated by using a scanning electron microscope (SEM). The structure of the membranes, on the other hand, was investigated by FTIR spectroscopy and WAXS structural analysis.

2

Study of the biodegradability of polylactide fibers in wastewater treatment processes

Rom M., Fabia J., Grübel K., Sarna E., Graczyk T., Janicki J.

Polimery

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2017

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T. 62, nr 11-12

834--840

EN

The aim of this research was to study what happens to polylactide (PLA) fibers when they are released to wastewater systems. Samples of PLA fibers were immersed in activated sludge and subjected to typical activated sludge treatment in mesophilic (36 °C) and thermophilic (56 °C) conditions for up to 4 weeks. The characteristics of the surface and cross-sections of PLA fibers were analyzed by scanning electron microscopy (SEM), showing the settlement of the microorganisms on the surface of PLA fibers immersed in sludge and also the erosion of the material with time. Differential scanning calorimetry (DSC) analysis provided information on small changes in the crystalline structure of PLA fibers, and the results of tensile tests proved only partial degradation of PLA material treated in the activated sludge system during the processing time. The study confirmed that the standard processing of wastewater in the activated sludge system, in both mesophilic and thermophilic variants, is insufficient for the biodegradation of PLA. Therefore, PLA microplastics can be released from wastewater treatment plants.

PL

Zbadano oddziaływanie osadu czynnego w procesach przebiegających w oczyszczalni ścieków na włókna polilaktydowe (PLA) uwolnione z wyrobów włókienniczych. Próbki włókien PLA umieszczano w osadzie ściekowym i poddawano klasycznemu procesowi oczyszczania ścieków metodą osadu czynnego, w procesie mezofilowym (36 °C) oraz termofilowym (56 °C), w ciągu 4 tygodni. Powierzchnię i przekrój poprzeczny włókien charakteryzowano z zastosowaniem skaningowej mikroskopii elektronowej (SEM). Wykazano zasiedlenie mikroorganizmami powierzchni włókien inkubowanych w osadzie czynnym oraz stopniową erozję badanego materiału. Na podstawie wyników badań metodą różnicowej kalorymetrii skaningowej (DSC) stwierdzono nieznaczne zmiany w strukturze krystalicznej włókien PLA, natomiast badania wytrzymałościowe potwierdziły częściową degradację włókien poddanych działaniu osadu ściekowego. Dowiedziono, że standardowe procesy oczyszczania ścieków metodą osadu czynnego, zarówno w wersji mezofilowej, jak i termofilowej, nie powodują biodegradacji PLA, dlatego też polilaktydowe mikrocząstki mogą być uwalniane z osadu ściekowego.

3

Inhibitors of thermally induced burn incidents – the examinations of the flammability, TGA, SAXS and SEM methods

Pielesz A., Gawłowski A., Fabia J., Ślusarczyk C., Sarna E.

Polimery

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2017

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T. 62, nr 11-12

806--811

EN

The examinations of the skin flammability, small-angle X-ray scattering (SAXS) and thermogravimetric (TGA) investigations were all carried out in temperature sufficient for simulating a burn incident. Above methods were used to perform assessment of collagen molecular structure changes in conditions of thermal oxidative stress, whereas the scanning electron microscopy analysis (SEM) was used to illustrate skin surface changes. The changes were observed in the presence of active antioxidants such as L-ascorbic acid, sodium ascorbate and hydrogel of orthosilicic acid H4SiO4 • n H2O. Presence of these modifiers of the burn process minimizes external effects of simulated burn incidents for model samples of animal skin and burn wound epidermis extracted from the patients. The examinations of the skin flammability were carried out with the limited oxygen index (LOI) method. In this study, synergy between orthosilicic acid and L-ascorbic acid and sodium ascorbate into animal and human skin has been shown through an increase in LOI values. The treatment by means of L-ascorbic acid affects particular morphological changes in the skin which is visible in SEM method. Skin samples incubated in the solution of the 3.5 %, 5 % L-ascorbic acid, 7 % sodium ascorbate solutions and 7 % orthosilicic acid demonstrate the development of a structure resembling a coherent solid composite. SAXS gives structural information on the assembly of dermal collagen as well as the lamellar organization of stratum corneum (SC) lipids located in the outermost part of the epidermis. Using this technique, two lamellar phases with repeat distance of approximately 4.3 and 6 nm in the SC lipids domains were observed. Moreover, the diameter of the collagen fibrils were extracted. The observed differences in the values of these parameters allowed us to better understand the mechanism of modification of the surface of the burn affected skin and the influence of the modification on the process of skin regeneration.

PL

Miejscowa oraz ogólna odpowiedź organizmu na oparzenie termiczne jest złożona. Nie tylko prowadzi do uszkodzenia skóry, ale wywołuje też głębokie długotrwałe zmiany w metabolizmie organizmu. Na podstawie wyznaczonego granicznego wskaźnika palności (LOI), wyników analizy termograwimetrycznej (TGA) i małokątowej dyfraktometrii rentgenowskiej (SAXS) oceniano zmiany zachodzące w strukturze kolagenu w warunkach stresu oksydacyjnego, a metodą skaningowej mikroskopii elektronowej (SEM) określano zmiany topografii powierzchni badanych próbek skóry. Modyfikowany aktywnymi przeciwutleniaczami, takimi jak: pochodne witaminy C (np. kwas L-askorbinowy, askorbinian sodu) oraz hydrożel kwasu ortokrzemowego H4SiO4 • n H2O. Kolagen wykazuje zwiększoną aktywność biochemiczną, a obecność niniejszych modyfikatorów procesu oparzeniowego minimalizuje zewnętrzne skutki symulowanych incydentów oparzeniowych.

4

Needle-punched fibrous polycaprolactone scaffold for bone tissue engineering

Rajzer I., Grzybowska-Pietras J., Fabia J., Sarna E.

Engineering of Biomaterials

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2013

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Vol. 16, no. 121

2--5

EN

In the present work a three dimensional composite scaffolds for bone tissue engineering were created by a carding and needle-punch processes. Highly porous nonwoven fabrics were obtained from PCL and PCL/n-HAp cut fibers without the use of any chemicals during the manufacturing process. The properties of nonwoven scaffolds were examined by SEM, FTIR, DSC and TGA methods. The average pore diameter as well as the pore size distribution of nonwoven fabrics were measured by a capillary flow porometry. The obtained results suggest that needle-punching method can be used to produce highly porous microstructures with an interconnected pore network.

5

Wpływ dodatków (nanorurek węglowych, montmorylonitu oraz pigmentu) na proces degradacji polipropylenu

Brzozowska-Stanuch A., Rabiej S., Sarna E., Maślanka M.

Przetwórstwo Tworzyw

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2012

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[R.] 18, nr 3

152-161

PL

W artykule przedstawiono wpływ dadatków (nanorurki węglowe, montmorylonit oraz pigment) na proces degradacji polipropylenu. Kompozyty otrzymano poprzez wprowadzenie do matrycy polimerowej wybranego dodatku o różnym stopniu rozdrobnienia. Przeprowadzone badania miały na celu scharakteryzowanie wpływu zarówno promieniowania UV, podwyższonej temperatury jak i udziału wilgoci na proces degradacji polipropylenu. Charakterystykę przebiegu procesu starzenia prowadzono w określonych odstępach czasu ekspozycji na zadane warunki symulujące starzenie atmosferyczne. Badano zmiany zachodzące na powierzchni w skali makroskopowej i mikroskopowej oraz wizualnie oceniano stan badanych próbek pod względem estetycznym i użytkowym. Oceniano także zmianę barwy próbek. Otrzymane wyniki przedstawiają wpływ zastosowanych dodatków na tempo starzenia polipropylenu jak i rozmiar zniszczenia materiału pod wpływem synchronicznego działania promieniowania UV, temperatury i wilgoci, na własności wyrobów polipropylenowych oraz prezentują przykładowe sposoby kontroli trwałości polimerów w czasie ich eksploatacji w warunkach atmosferycznych.

EN

The paper presents influence of additives (carbon nanotubes, montmoryllonite, pigment) on the process of degradation of polypropylene. The composites were obtained by introduction of the selected additive to the polymer matrix with varying degree of refining. The study aimed in characterization the effect of UV radiation, elevated temperature and moisture on the degradation process of polypropylene. The characterization of the aging process was carried out at defined intervals of exposure time to the given factors, simulating atmospheric conditions. The changes were tested on the surface of samples in macro-and microscopic scale. The condition of tested samples was visually assessed in terms of aesthetic qualities, functionality and changes in their color. Results of these investigations show the effect of the additives on the rate of aging of polypropylene and degree of material damage due to synchronous operation of UV radiation, temperature and moisture on the properties of polypropylene and present the methods of polymer durability control during exploitation in outdoor conditions.

6

Influence of UV irradiation and temperature on polyamides PA6, PA6,6 and polypropylene PP

Brzozowska-Stanuch A., Rabiej S., Sarna E., Maślanka A.

Polish Journal of Applied Chemistry

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2011

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Vol. 55, nr 3-4

115-122

EN

In outdoor applications, all polymer materials weather which causes deterioration of their mechanical properties and has a negative influence on their appearance. In this article, the influence of UV irradiation and high temperature on polyamides PA6, PA6.6 and polypropylene PP and influence of aging parameters on their appearance (the state of surface) and chemical crystal structure have been shown. Microscopic examination of samples has shown that the biggest destruction in the surface of PP occurred in a short time after the beginning of the exposure. The examination of the surface and crystal structure of the materials clearly indicated that during exposure to UV irradiation and temperature degradation in PP materials occurred. Polyamides showed longer reaction time but after some time they also underwent radical changes in their supermolecular structure and they lost their esthetic appearance.

7

Mineralization and degradation of poly(ε -caprolactone) / hydroxyapatite electrospun membranes

Rajzer I., Kwiatkowski R., Sarna E., Janicki J.

Engineering of Biomaterials

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2011

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Vol. 14, no. 106-108

5--9

EN

The aim of this work was to study mineralization and degradation behavior of poly(ε-caprolactone) membranes modified with hydroxyapatite. The membranes have been obtained by electrospinning method. In vitro mineralization and degradation processes were carried out in simulated body fluid (SBF) as the release medium. The weight loss of the samples, water uptakes, pH and calcium, potassium, sodium ions concentrations of the solutions were determined. The chemistry and microstructure of the membranes after different times of incubation in SBF were characterized using SEM, FTIR, and XRD methods. The results of in vitro study in SBF indicate that incorporation of n-HAp strongly activates precipitation of the apatite like materials on the surface of nanofibers.

8

Antibacterial activity and scanning electron microscopy (SEM) examination of alginate-based films and wound dressings

Pielesz A., Machnicka A., Sarna E.

Ecological Chemistry and Engineering. S

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2011

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Vol. 18, nr 2

197-210

EN

Natural polymers widely used to produce drug carriers and active dressings include alginates, gelatine, chitosan and hyaluronic acid. In this study, alginate films were obtained bypassing the process of lyophilization. Produced from the common bladder wrack (Fucus vesiculosus L.), they can be used in food chemistry, wound treatment (tissue infections, burns) and in skin care; they are also good drug carriers. The films were examined for their bacteriostatic effects. Alginate gels exhibit bacteriostatic properties against Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus. Tests conducted for active dressings revealed that Aquacel Ag and gauze soaked with 1% AgNO3 exhibit bacteriostatic properties against E. coli and no resistance against S. aureus. Examination using scanning electron microscopy (SEM) confirmed the bacteriostatic properties of the Aquacel Ag dressing and gauze with 1% AgNO3. Dead cultures of Staphylococcus aureus were observed on the fibre surface of both dressings.

PL

Naturalne polimery są szeroko używane do opatrunków aktywnych na bazie: alginianów, żelatyny, chitozanu i kwasu hialuronowego. W przedstawionych badaniach błonę alginianową otrzymuje się, omijając liofilizację. Żel otrzymano z morszczynu pęcherzykowatego (Fucus vesiculosus L.) wykorzystywanego powszechnie w chemii żywności, leczeniu ran (zakażeniach tkanek, oparzeniach), pielęgnacji skóry oraz jako nośnik leków. Badane żele alginianowe wykazywały właściwości bakteriostatyczne w stosunku do bakterii Gram-dodatnich Staphylococcus ureus oraz bakterii Gram-ujemnych Escherichia coli. Testy przeprowadzone dla aktywnych opatrunków wykazały, że Aquacel Ag i gaza nasączona 1% AgNO3 wykazują właściwości bakteriostatyczne w stosunku do S. ureus i E. coli. Badanie za pomocą skaningowego mikroskopu elektronowego (SEM) potwierdziło właściwości bakteriostatyczne Aquacel Ag i opatrunku z gazy nasączonym 1% AgNO3. Na powierzchni włókien obu opatrunków zidentyfikowano obumarłe kultury S. aureus i E. coli.

9

Biomimetic fibrous composite membranes for bone tissue engineering

Rajzer I., Chrzanowski W., Biniaś W., Sarna E., Janicki J.

Engineering of Biomaterials

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2010

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Vol. 13, no. 93

2--5

EN

One of the major challenges in biomaterials and tissue engineering is to guide the cell differentiation to the specific phenotype, therefore allow the formation of the tissue of certain type. This can be achieved by manipulating the structural, geometrical and chemical characteristics of the tissue engineering constructs. In our studies we concentrated on the chemical modifications of the polymer based materials for tissue engineering. The primary aim of our study was to incorporate nano size hydroxyapatite (n-HAp) crystals into the polymer fibres and form membranes, which are a core to the construction of novel scaffolds for tissue regeneration. We hypothesised that n-HAp will significantly improve the bioactivity of the polymer based membranes due to the presence of chemical cues. We developed a simple method to fabricate PLDL/n- HAp composite membranes using electrospinning process. The investigation showed that the incorporation of the n-HAp particles in the polymer spinning solution induced changes in the material surface morphology. FTIR analysis confirmed the presence of apatite on the surface of the membrane' fibers. The bioactivity analysis, which was based on SEM observation of the membranes surface, showed that after only 7 days immersion in SBF, the PLDL/n-HAp -membranes were completely covered by the apatite layer. This was not observed for pure PLDL membranes.

10

Effect of simulated body fluid on the microstructure of melt spun composite fibers

Rajzer I., Rom M., Fabia J., Sarna E., Biniaś D., Zima A., Ślósarczyk A., Janicki J.

Engineering of Biomaterials

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2009

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Vol. 12, no. 88

2--4

EN

Polylactic acid (PLA) offers unique features of biodegradability and thermal processability, that offer potential applications in medicine. PLA can be transformed into fibers by spinning enabling then subsequent fabrication of desirable three dimensional fabrics which may be used as scaffolds for tissue engineering applications. Incorporation of synthetic nano-hydroxyapatite into the fibrous polymer matrix can enhance bioactive properties of the prospective scaffold. In the present work, the method of production of composite fibers based on polylactic acid (PLA) and nano-hydroxyapatite (n-HAp) is proposed. Obtained fibers have shown excellent apatite-forming ability when immersed in simulated body fluid.

11

Analysis of Cotton Maturity Degree on Microstructure Level by Fuzzy Set Conception

Sarna E., Rabiej M., Sarna M., Włochowicz A.

Fibres & Textiles in Eastern Europe

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2008

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Vol. 16, no. 1 (66)

13--18

EN

This paper is a continuation and generalisation of an earlier study of cotton maturity degree determination in the earlier paper. Up till now the maturity degree of cotton has been determined by the analysis of longitudinal outside views of cotton fibres. Early, we proposed a method of cotton maturity determination based on SEM images of cotton fractures. Fuzzy set conception was adopted to analyse each image, considering the fracture category. In this paper have emphasized the fuzzy aspects of cotton maturity determination by analysing the longitudinal outside views of cotton in accordance with the “Russian-standard”, and by using a new method for determination, which is based on analysing SEM images of cotton fractures proposed by as.

PL

Przedstawiona praca stanowi kontynuację wcześniejszych badań nad wyznaczaniem stopnia dojrzałości bawełny do tej pory wyznaczanego na podstawie analizy wzdłużnego, zewnętrznego widoku włókna bawełny. W wcześniejszej pracy zaproponowano metodę wyznaczania dojrzałości bawełny na podstawie analizy obrazów SEM przełomów włókien bawełny. Do analizy cech obrazów przełomów włókien została zastosowana koncepcja zbiorów rozmytych. W prezentowanym opracowaniu zastosowano elementy zbiorów rozmytych również do oceny wzdłużnego widoku włókna. Utworzono „wzorzec rozmyty” bazując na tzw. „Standardach Radzieckich”. Miara „zbliżenia” zbioru rozmytego jest użytecznym narzędziem do wyznaczania stopnia dojrzałości bawełny.

12

Determination of maturities degree on the base of SEM images cotton fracture with elements of fuzzy sets theory

Sarna E., Włochowicz A., Sarna M.

Archives of Materials Science

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2007

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Vol. 28, nr 1-4

124-130

EN

Purpose: The goal of presented research is to establish a better method for determination of the cotton maturity degree. Methodology: For imaging of the cotton fracture Scanning Electron Microscopy is used. For classification of the cotton fracture elements of Fuzzy Sets theory is applied. Findings: A method of maturity determination based on SEM images and elements of fuzzy sets theory is proposed. The presented method appeared to be more precise than the maturity reference standard method. Research implication: Method of the analysis of SEM images with fuzzy sets enables to perform a quantitative analysis of the cotton fractures images. This method will be improved with a computer method. Practical implications: An effective method for measurement of cotton fibres maturity is developed. Originality: Classification of images of cotton fracture, identification of images with fuzzy set theory conception.

13

Przełomy bawełny o różnym stopniu dojrzałości

Sarna E., Włochowicz A.

Archiwum Nauki o Materiałach

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2001

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T. 22, nr 2

115-127

PL

Badano bawełnę syryjską o stopniach dojrzałości od 0,5 do 3,0 metodą skaningowej mikroskopii elektronowej (SEM). Przełomy włókien badano w trybie elektronów wtórnych (SE), przy powiększeniach od 1.000x do 15.000x. Zaobserwowano wyraźną zmianę kształtu przełomu wraz ze zmianą stopnia dojrzałości bawełny. Przełomy analizowanych włókien dostarczają cennej informacji o przebiegu procesu rozrywania włókna.

EN

Syrian cotton of maturity degree range from 0.5 to 3.0 has been investigated by scanning electron microscopy (SEM). Fractures of fibres have been investigated in the mode of secondary electrons (SE), at magnifications from 1.000x to 15.000x. A distinct change of shape of fracture together with the change of maturity degree, was observed testifying changes of fibre structure in the ripening process. The fracture of these fibres delivers the precious information about the course of the process of fibre tearing.

14

Zastosowanie mikroskopów skaningowych JSM-15 JEOL i S-4200 HITACHI do badania barwionych włókien polipropylenowych

Sarna E., Włochowicz A., Broda J.

Przegląd Włókienniczy + Technik Włókienniczy

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1998

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nr 4

8-11

PL

W pracy przedstawiono badania morfologii powierzchni i przekrojów poprzecznych włókien polipropylenowych przy zastosowaniu mikroskopu JSM-15 JEOL i S-4200 HITACHI. W prezentowanych badaniach mikroskopowych poszukiwano różnic w budowie morfologicznej powierzchni włókien bezbarwnych i barwionych. Jednocześnie porównywano możliwości badawcze mikroskopu JSM-15 JEOL i S-4200 HITACHI.