Sociedade Brasileira de Química (SBQ)
Polyvinyl butyral (PVB) from laminated-glass
waste for printable photonic devices
Diana R. S. da Silva (PG)* e Petrus A. Santa-Cruz (PQ)
*[email protected]
Departamento de Química Fundamental, Universidade Federal de Pernambuco, 50740-540, Recife-PE
Keywords: PVB, laminated-glass, thermal evaporation, printable films, Europium nanofilms.
Laminated-glasses materials consist of a sandwich
comprising a core polymer (PVB in the present case)
between glass sheets. It presents greater safety in
case of impact, protection against ultraviolet
1
radiation and improvements in acoustic insulation .
The objective of this work is the establishment
separation processes and characterization of PVB
films obtained from this discarded material (usually
from laminated glass of car windshields) previously
for encapsulating photonics devices produced in our
2
group , and currently to study the feasibility of the
printable form of these devices, allying the optical
and thermochemical properties of the polymer by
spectroscopic and thermal characterization.
In order to study the PVB volatility by sublimation and
the optical properties besides a molecular photonic
film, it was conducted the deposition of a europium
complex following by a deposit the polymer both by
thermo-evaporation in an AUTO 306 BOC Edwards
device, monitored by optical spectra, shown in fig.3.
100
95
Transmittance (%)
Introduction
90
85
Eu(btfa)3bipy + PVB
80
PVB
Eu(btfa)3bipy
75
70
300
400
500
600
700
800
900
1000
(nm)
Results and Discution
The PVB film obtained from mechanical separation
of windshield automotive glass was analyzed after
removal of any dirt by organic solvents chosen by the
lower boiling point and toxicity and non-reactivity with
the polymer. The PVB characterization was started
by TGA and optical spectroscopy. TGA analyzes
were performed with masses of 10 mg of PVB
shredded in small platinum crucibles, heated to 600
°C at a rate of 10 °C/min, resulting in the weight loss
according fig. 1, for recycled and commercial forms.
1,1
Reciclado
Comercial
1,0
0,9
Normalized Mass
0,8
Figure 3: UV-Vis-IR spectra of films deposited by
thermal-evaporation.
Conclusions
To start the separation process of the PVB from the
vitreous waste as starting material, the best solvent
identified was ethanol, among all solvents tested.
Preliminary results were analyzed to establish the
process using PVB as the basis of printable
molecular devices dispersed in the polymer as
nanocomposites with molecular active parts. The
first results of sublimation were obtained in AUTO
306 equipment by vacuum controlled thermal
evaporation, resulting in a good assembly of polymer
and molecular complex film.
0,7
0,6
0,5
a)
0,4
0,3
b)
Congratulations
0,2
0,1
0,0
100
200
300
400
500
600
700
800
Temperature (°C)
Figure 1. a) TGA and b) UV-Vis-IR transmission
spectra of recycled and commercial PVB.
Transmittance in UV-Vis-IR range resulted in very
satisfactory transparent films in visible-IR region
which let pass the light and block selectively UV in
both PVB samples, as shown in figure 2.
36a Reunião Anual da Sociedade Brasileira de Química
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1
Cho, C. H.; Cho, M. S.; Sung, J. H,; Chol, H. J.; Jhon,
M. S. J. Mat. Science, 39(9): 3151-3153, 2004.
2
G.F. de Sá, O.L. Malta, C. Donegá, A. M. Simas, R. L.
Longo, P. Santa Cruz, E.F. Silva Jr., (Coordination
Chemical Review,196, 2000, 165.