Physico-Chemical nanomaterials science
Wettability and surface properties of plasma treated paper-based composite surface
Chodkowski M.1, Terpiłowski K.1, Nastaj M.2
1 Department of Interfacial Phenomena, Institute of Chemical Sciences, Faculty of Chemistry, Maria Curie-Skłodowska University in Lublin
Sq. M. Curie-Skłodowska 3, 20-031 Lublin, Poland
E-mail: michal.chodkowski@poczta.umcs.lublin.pl
2 Department of Milk Technology and Hydrocolloids, University of Life Sciences, Skromna 8, Lublin, 20-704, Poland.

Plasma is an ionized quasi-gas which is a mixture of electrically charged particles such as ions or electrons as well as neutral particles. One of interesting aspect of plasma applications is modification of solids properties because during the process only the top layer of a material is treated. Due to that it can be apply for modify and functionalize the surface of nanomaterials [1]. Plasma modification becomes more and more popular techniques nowadays because surface properties of various materials play a key role for determining the material applications.
The aim of the study was comparison of surface properties of plasma modified paper-based composite samples. The substrates were activated by air plasma for 10 or 30 seconds. Then the contact angle measurements by the sessile droplet method were made to examine wettability of the surfaces and the equilibrium contact angle was calculated using the Tadmor’s equation [2]. The surface free energies were also calculated using the contact angle hysteresis (CAH) method proposed by Chibowski [3] in order to compare the properties of the obtained surfaces. To get information about substrates structure after the plasma modification optical profilometers were made.
It was found that the wettability of composite surface as well as its topography were changed after the plasma processing. The top layer became more hydrophilic; some differences in the surface roughness were observed.

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