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1

Surface Modification of Solids by Extreme Ultraviolet and Plasma Treatment

100%

Bartnik A., Fiedorowicz H., Skrzeczanowski W., Czwartos J., Wachulak P., Jarocki R., Kostecki J.

Acta Physica Polonica A

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2018

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vol. 133

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issue 2

267-270

EN

In this paper, results of surface modification, using a laser-produced plasma source of extreme ultraviolet, and the extreme ultraviolet induced low temperature plasmas, are presented. It was shown that irradiation of different materials by intense extreme ultraviolet pulses results in strong changes of the surface morphology. Examples of micro- and nanostructures obtained this way are presented. It was also demonstrated that a dual action of the radiation pulses and low temperature plasmas allows to modify a molecular structure of exposed materials.

2

Influence of surface treatment on the wetting process of jute fibres with thermosetting polyester resin

88%

Bogdan-Włodek A., Kozioł M., Myalski J.

Polish Journal of Chemical Technology

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2012

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vol. 14

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issue 1

21-27

EN

The aim of this study is the evaluation of the effect of chemical treatment of jute fibres on their permeability with polyester resin and determination of optimal treatment parameters. Unmodified jute fabric by LENTEX, Poland and polyester resin ESTROMAL 14 were used in the experiments. NaOH and KOH water solutions (various concentration - from 1 to 15% - and treatment duration - from 0.5 to 6h), vinyl acetate, methanol, toluene diizocyanate were used for the treatment. Determination of the effect of the chemical treatment on fiber-resin interaction was made in: infiltration of resin into reinforcement structure tests and fabric absorbability tests. Three criteria: time of penetration of resin into the reinforcing fabric, fabric absorbability and the area of a part of the specimen cross-section penetrated with the resin were taken into account. The fabrics treated with 1-5% - long-time and 15% short-time NaOH and KOH water solutions showed the best results within the tested criteria. These results do not correspondent directly with the mechanical properties of cured composites manufactured on the base of the treated fabrics. Alkali- and organic treatments significantly improve the mechanical performance of natural fibres reinforced composites, but organic treatments (methanol, toluene diisocyanate) gives better improvement in mechanical properties in comparison with the alkali-treatments. The measurement methods applied in the study may be generally useful in the evaluation of the effect of chemical treatment of natural fibres on their wettability with the liquid matrix.

3

Polylactic acid surface activation by atmospheric pressure dielectric barrier discharge plasma

88%

Hergelová B., Zahoranová A., Kováčik D., Stupavská M., Černák M.

Open Chemistry

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2015

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vol. 13

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issue 1

EN

Polylactic acid (PLA) is suitable for applications in packaging and biomedicine due to its biodegradability. To improve PLA surface adhesion a plasma-chemical treatment using nonthermal plasma generated in ambient air via diffuse coplanar surface barrier discharge (DCSBD) was used. The optimal treatment time and power were investigated. Interaction between active plasma species and the polymer surface, and the resulting surface changes were studied by contact angle measurement, surface energy determination, FTIR, and XPS. The most hydrophilic surface was obtained after only 3–4 s treatment. Treatment up to 10 s did not damage the polymer but longer treatments (30 and 60 s) caused partial degradation. The plasma broke C-C/C-H bonds and formed more C-O, O-C=O and C-O-C bonds. During storage surface oxygen decreased and a negligible amount of nitrogen was adsorbed. The oxygen-containing functional groups probably sank into the PLA volume after treatment.

4

Influence of wet chemistry treatment on the mechanical performance of natural fibres

88%

Koziol M., Bogdan-Wlodek A., Myalski J., Wieczorek J.

Polish Journal of Chemical Technology

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2011

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vol. 13

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issue 4

21-27

EN

The paper presents determination of the effect of various chemical treatment on the strength of 288 tex jute yarn arisen from the plain weave fabric produced by LENTEX, Poland. The yarn was put to alternative treatments in: NaOH and KOH water solutions with various concentration (from 1 to 15%) and treatment duration (from 0.5 to 6 hours), vinyl acetate, methanol and toluene diisocyanate. After the treatment it was put to tensile tests. Yarn diameter and elementary fibre twist angle were also measured using MICRO PROF FRT optical profilographometer. The SEM micro-photographs have also been performed in order to evaluate the structural changes of the yarn after the treatment.Optimal conditions of alcali-treatment are: 5% concentration and 2h duration for NaOH, 3% concentration and 4h duration for KOH. Such treatments give a growth in yarn rupture force up to 10% and they are well applicable in composite materials manufacturing. Also interaction with vinyl acetate and toluene diisocyanate has practically not negative influence on the mechanical performance of the yarn. Two effects were observed which can explain the influence of chemical treatment on mechanical performance of jute yarn: swelling and change in the orientation of elementary fibres.

5

DEVELOPMENT OF HYDROPHOBIC SURGICAL FORCEPS USING POWDER INJECTION MOLDING AND SURFACE TREATMENT

75%

Park D. Y., Park B. R., Gal C. W., Lin D., Han J. S., Jeong M.-S., Bollina R., Hwang W., Park S. J.

Archives of Metallurgy and Materials

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2018

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vol. 63

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issue 1

Refine search results

Surface Modification of Solids by Extreme Ultraviolet and Plasma Treatment

Influence of surface treatment on the wetting process of jute fibres with thermosetting polyester resin

Polylactic acid surface activation by atmospheric pressure dielectric barrier discharge plasma

Influence of wet chemistry treatment on the mechanical performance of natural fibres

DEVELOPMENT OF HYDROPHOBIC SURGICAL FORCEPS USING POWDER INJECTION MOLDING AND SURFACE TREATMENT