XIV
h
International Conference on Molecular Spectroscopy, Białka Tatrzańska 2017
205
T1: P–72
Structural and microstructural comparison of bioactive glasses from
binary system obtained by different methods
Aleksandra Wajda
1
, and Maciej Sitarz
1
1
Faculty of Materials Science and Ceramics, AGH University of Science and Technology,
Mickiewicza 30, 30-059 Cracow, Poland, e-mail: olawajda@agh.edu.pl
Bioactive glasses and glass ceramics have been extensively investigated for applications as
bone implants because of their ability to form a bond to living bone when they are in contact
with biological fluids [1]. Bioactive glasses can be obtained by both conventional melt-
quenching route and by low-temperature chemistry-based sol-gel process. The structure,
microstructure and levels of bioactivity are influenced not only by the glass composition, but
also by synthesis routes: melting versus sol–gel [2]. Thus, it is important to compare, with the
use of the same instrumental analysis methods, the physical and chemical properties of bioactive
glass powders from identical system produced through melting and sol-gel process [3].
Two bioactive glasses from SiO
2
-CaO system were obtained by sol-gel and melting
techniques. The effect of two different glass obtaining methods was investigated using X-ray, IR
and Raman spectroscopy. The measurements allowed to show the significant differences in the
glasses structure. BET analysis provided information about precise specific surface area
evaluation of the obtained materials. Moreover microstructure bioactivity and thermal properties
of all glasses were compared to demonstrate differences in applications properties.
Keywords: bioactive glasses; FTIR spectroscopy; glass structure; sol-gel derived glass; melt-derived glass
Acknowledgment
This work was supported by NCN project “Bioactive silico-phosphate glassy and glass-crystalline materials
containing antibacterial ions 2016/20/T/ST8/00204”.
References
[1] L.L. Hench, J.K. West, Biological applications of bioactive glasses, Life Chem. Rep. 13 (1996) 187.
[2] P. Sepulveda, J.R. Jones, L.L. Hench, J. Biomed. Mater. Res. 61 (2002) 301.
[3] D.C. Greenspan, J.P. Zhong, X.F. Chen, G.P. La Torre, Bioceramics. 10 (1997) 391.
XIV
h
International Conference on Molecular Spectroscopy, Białka Tatrzańska 2017
206
T1: P–73
Spectroscopic studies of structural interactions
in silicate-borate-phosphate glass
Barbara Łagowska
1
, Maciej Sitarz
1
, and Magdalena Szumera
1
1
AGH University of Science and Technology, Faculty of Materials Science and Ceramic,
Department of Ceramics and Refractories, 30 A. Mickiewicza av., 30-059, Krakow, Poland,
e-mail: mszumera@agh.edu.pl
Glass, in its various forms, represents one of the largest single outlet for boron products.
Boron is a powerful glass component and also confers high chemical resistance for glasses in
general. As a component it works by reducing melting point, viscosity, thermal expansion
coefficient, and increasing transparency and brightness, and even heat resistance of the glass.
Almost every time the use of boron improves fluxing capabilities of a batch, reduces glass batch
melting temperature and also reduces the tendency of glass to crystallization.
These specific properties arise from a structural role played by boron in the glass structure.
Boron is a network former and is fully integrated to the glass structure in the form of different
structural units, in which its coordination can be either three-fold and/or four-fold. Its role and
influence on the glass structure is well known. It mainly concerns borosilicate and
borophosphate glass, which contains two types of network formers ie. SiO
2
and P
2
O
5
. Due to the
lack of literature data about glass additionally containing B
2
O
3
in its composition, the structural
features of boron in silicate-borate-phosphate glass are reviewed. The different boron-containing
units and spectroscopic techniques (X-ray method, SEM-EDS, Raman and MAS-NMR
spectroscopies) used to identify them are described.
Glasses from a SiO
2
-P
2
O
5
-K
2
O-CaO-MgO system modified by B
2
O
3
addition were analysed.
The increasing amount of B
2
O
3
was introduced at the cost of the decreasing amount of MgO and
CaO, with the constant MgO/CaO ratio. It has been found that the range of glass forming ability
is high, and samples containing up to 28 mol. % of B
2
O
3
were amorphous. Simultaneously,
phase separation was found in the samples containing above 10% mol. of B
2
O
3
. Using
spectroscopic methods it was found that the analysed glass samples contained triangular and
tetrahedral boron groups along with Si–O and P–O vibtarions. The structural studies indicate the
coexistence of BO
3
and BO
4
structural groups but only in the case of higher content of B
2
O
3
in
the glass chemical composition (above 12 mol.%). The existence of Si–O–Si, P–O–P and
B–O–Si vibrations was also confirmed
In summary, it is concluded that the increasing content of B
2
O
3
in the structure of glass from
SiO
2
-B
2
O
3
-P
2
O
5
-K
2
O-MgO-CaO system results in gradual increase of degree of silicate-borate-
phosphate framework polymerization.
Keywords: silicate glasses; FTIR; Raman and MAS NMR spectroscopy
Acknowledgments
The work was supported by Faculty of Materials Science and Ceramics, AGH University of Science and
Technology No11.11.160.617.
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