XIV
h
International Conference on Molecular Spectroscopy, Białka Tatrzańska 2017
160
T1: P–27
Examination of doped zirconia-based layers deposited on metallic
substrates
Magdalena Gawęda
1
, Elżbieta Długoń
1
, Piotr Jeleń
1
, Magdalena Leśniak
1
,
Renata Jadach
1
, Aaleksandra Wajda
1
, Magdalena Szymańska, and Maciej Sitarz
1
1
Department of Silicate Chemistry and Macromolecular Compounds, Faculty of Materials Science
and Ceramics, AGH University of Science and Technology, 30 Mickiewicza Av., 30-059 Krakow,
Poland, e-mail: mgaweda@agh.edu.pl
The work is focusing on the spectroscopic examination of zirconia-based layers deposited on
metallic substrates. Metallic biomaterials belong to the group of best known and most widely
applied materials in medicine. They might be characterised with the easiness of formation and
good mechanical properties. However, the surface properties of the material need to be strictly
controlled, to prevent corrosion processes and ensure biocompatibility [1]. One of the
modifications leading to improvement of the properties important in terms of considering the
material for biomedical applications is the fabrication of ceramic layers on the surface.
Presented zirconia-based layers doped with calcium and hydroxyapatite were obtained using
the sol-gel method and deposited on the metallic (titanium and steel) surface with the use of dip-
coating technique and electrophoretic deposition (EPD) [2]. Obtained layers were examined
with multiple spectroscopic and microscopic method, such like Raman spectroscopy, X-ray
photoelectron spectroscopy (XPS), energy dispersive spectroscopy (EDS), scanning electron
microscopy (SEM) and laser confocal microscopy (LCM). Bioactivity of the obtained layers
was evaluated by the in vitro test in stimulated body fluid (SBF) - the so-called Kokubo test [3].
Keywords: biomaterial; bioactivity; ceramic coatings; sol-gel; EDP
Acknowledgments
This work was supported by the NCN project “Functional layers of black glasses based on ladder-like
silsesquioxanes 2014/15/B/ST8/02827”.
References
[1] R.I.M. Asri, W.S.W. Harun, M. Samykano, N.A.C. Lah, S.A.C. Ghani, F. Tarlochan, M.R. Raza,
Mater. Sci. Eng. C 77 (2017)1261-1274.
[2] N. Petkova, S. Dlugocz, S. Gutzov, J. Non-Cryst. Solids 357 (2011) 1547.
[3] T. Kokubo, H. Takadama, Biomaterials 27 (2006) 2907.
XIV
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International Conference on Molecular Spectroscopy, Białka Tatrzańska 2017
161
T1: P–28
Influence of Si-H groups on thermal decomposition of PMHS networks
with introduced Q units
Monika Wójcik-Bania
1,2
, Agnieszka Łącz
2
, Anna Nyczyk-Malinowska
2
,
and Magdalena Hasik
2
1
Faculty of Geology, Geophysics and Environment Protection, AGH University of Science and
Technology, Al. Mickiewicza 30, 30-059 Kraków, Poland, e-mail: wojcikm@agh.edu.pl
2
Faculty of Materials Science and Ceramics, AGH University of Science and Technology,
Al. Mickiewicza 30, 30-059 Kraków, Poland
In the present work, the influence of Si-H groups on thermal decomposition of
poly(methylhydrosiloxane) (PMHS) networks with introduced Q units has been studied. The
networks have been obtained by cross-linking of PMHS with branched, tetrafunctional
tetrakis(vinyldimethylsiloxy)silane (Q(M
Vi
)
4
). Due to the presence of hydrogen atom at each
silicon atom in PMHS chain, systems containing various amounts of unreacted Si–H groups can
be prepared by changing the amount of Q(M
Vi
)
4
in the crosslinking process. The hydrosilylation
reaction was carried out in the presence of Karstedt catalyst at three molar ratios of Si–H groups
to Si–CH=CH
2
: 1.5:1, 3:1 and 6:1. Small, medium and high contents of unreacted Si–H groups
in polysiloxane networks were obtained. The presence of Si–H groups in the systems after cross-
linking process was confirmed by FTIR spectroscopy.
Parameters of PMHS(Q(M
Vi
4
) networks i.e., cross-linking densities and average molecular
weight between crosslinks have been determined based on swelling measurements in THF.
Thermal properties of the studied systems have been examined by thermogravimetric analysis
(TG), based on which derivative (DTG) curves have been constructed. Mass spectrometry (MS)
has been used to analyze gaseous products released during thermal degradation of the polymer
networks. Cross-linked systems were subjected to pyrolysis in Ar atmosphere at various
temperatures: 200, 350, 530, 600, 700 and 1000°C which were determined based on DTG
curves. Pyrolysis products have been analyzed by FTIR spectroscopy and XRD diffraction. The
conducted investigations allowed to conclude that the amount of Si–H groups affects the number
of decomposition steps and thus influences the rate of thermal degradation of the studied
systems.
Fig. 1. Structure of the polymer and the cross-linking agent applied in hydrosililation reactions.
Keywords: PMHS networks; Si-H groups; polysiloxane thermal decomposition
Acknowledgment
The work was partially financed by Polish National Science Center (NCN) project number
014/13/B/ST5/01924 and Dean’s Grant number 15.11.140.994.
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