Dielectric and pyroelectric properties of the composites of ferroelectric ceramic and poly(vinyl chloride)
The dielectric and pyroelectric properties of lead zirconate titanate/poly(vinyl chloride) [PZT/PVC] and barium titanate/poly(vinyl chloride) [BaTiO₃/ PVC] composites were studied. Flexible composites were fabricated in the thin films form (200−400 µm) by hot-pressed method. Powders of PZT or Ba...
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irk-123456789-1207032017-06-13T03:03:05Z Dielectric and pyroelectric properties of the composites of ferroelectric ceramic and poly(vinyl chloride) Olszowy, M. The dielectric and pyroelectric properties of lead zirconate titanate/poly(vinyl chloride) [PZT/PVC] and barium titanate/poly(vinyl chloride) [BaTiO₃/ PVC] composites were studied. Flexible composites were fabricated in the thin films form (200−400 µm) by hot-pressed method. Powders of PZT or BaTiO₃ in the shape of 6 75 µm ceramics particles were dispersed in a PVC matrix, providing composites with 0−3 connectivity. Distribution of the ceramic particles in the polymer phase was examined by scanning electron microscopy. The analysis of the thermally stimulated currents (TSC) have also been done. The changes of dielectric and pyroelectric data on composites with different contents of ceramics up to 40% volume were investigated. The dielectric constants were measured in the frequency range from 600 Hz to 6 MHz at room temperature. The pyroelectric coefficient for BaTiO₃/PVC composite at 343 K is about 35 µC/m²K which is higher than that of β-PVDF (10 µC/m²K). Досліджено діелектричні і піроелектричні властивості композитів цирконату свинцю/полі(вінил хлориду) та титанату барію/полі(вінил хлориду). Еластичні композити виготовлено у вигляді тонких плівок (200−400 мкм) методом гарячого пресування. Порошки PZT та BaTiO₃ у вигляді керамічних частинок з діаметром меншим за 0.75 мкм розпилено в матриці полівінилхлориду, при чому утворилися композити зі зв’язністю 0−3. Розподіл керамічних частинок у полімерній фазі досліджено за допомогою електронного скануючого мікроскопа. Також проведено аналіз термічно стимульованих струмів. Досліджено зміни діелектричних і піроелектричних характеристик композитів при зміні вмісту кераміки до 40%. Діелектричні сталі виміряні у частотному діапазоні від 600 Гц до 6 МГц при кімнатній температурі. Піроелектричний коефіцієнт композиту BaTiO₃/PVC при 343 K складає 35 мкКл/м²K, що вище, ніж у β-PVDF (10 мкКл/м²K). 2003 Article Dielectric and pyroelectric properties of the composites of ferroelectric ceramic and poly(vinyl chloride) / M. Olszowy // Condensed Matter Physics. — 2003. — Т. 6, № 2(34). — С. 307-313. — Бібліогр.: 8 назв. — англ. 1607-324X PACS: 77.84.L, 77.70, 77.84.D DOI:10.5488/CMP.6.2.307 http://dspace.nbuv.gov.ua/handle/123456789/120703 en Condensed Matter Physics Інститут фізики конденсованих систем НАН України |
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Digital Library of Periodicals of National Academy of Sciences of Ukraine |
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| language |
English |
| description |
The dielectric and pyroelectric properties of lead zirconate titanate/poly(vinyl
chloride) [PZT/PVC] and barium titanate/poly(vinyl chloride) [BaTiO₃/
PVC] composites were studied. Flexible composites were fabricated in the
thin films form (200−400 µm) by hot-pressed method. Powders of PZT or
BaTiO₃ in the shape of 6 75 µm ceramics particles were dispersed in a
PVC matrix, providing composites with 0−3 connectivity. Distribution of the
ceramic particles in the polymer phase was examined by scanning electron
microscopy. The analysis of the thermally stimulated currents (TSC)
have also been done. The changes of dielectric and pyroelectric data on
composites with different contents of ceramics up to 40% volume were investigated.
The dielectric constants were measured in the frequency range
from 600 Hz to 6 MHz at room temperature. The pyroelectric coefficient for
BaTiO₃/PVC composite at 343 K is about 35 µC/m²K which is higher than
that of β-PVDF (10 µC/m²K). |
| format |
Article |
| author |
Olszowy, M. |
| spellingShingle |
Olszowy, M. Dielectric and pyroelectric properties of the composites of ferroelectric ceramic and poly(vinyl chloride) Condensed Matter Physics |
| author_facet |
Olszowy, M. |
| author_sort |
Olszowy, M. |
| title |
Dielectric and pyroelectric properties of the composites of ferroelectric ceramic and poly(vinyl chloride) |
| title_short |
Dielectric and pyroelectric properties of the composites of ferroelectric ceramic and poly(vinyl chloride) |
| title_full |
Dielectric and pyroelectric properties of the composites of ferroelectric ceramic and poly(vinyl chloride) |
| title_fullStr |
Dielectric and pyroelectric properties of the composites of ferroelectric ceramic and poly(vinyl chloride) |
| title_full_unstemmed |
Dielectric and pyroelectric properties of the composites of ferroelectric ceramic and poly(vinyl chloride) |
| title_sort |
dielectric and pyroelectric properties of the composites of ferroelectric ceramic and poly(vinyl chloride) |
| publisher |
Інститут фізики конденсованих систем НАН України |
| publishDate |
2003 |
| url |
http://dspace.nbuv.gov.ua/handle/123456789/120703 |
| citation_txt |
Dielectric and pyroelectric properties of
the composites of ferroelectric ceramic
and poly(vinyl chloride) / M. Olszowy // Condensed Matter Physics. — 2003. — Т. 6, № 2(34). — С. 307-313. — Бібліогр.: 8 назв. — англ. |
| series |
Condensed Matter Physics |
| work_keys_str_mv |
AT olszowym dielectricandpyroelectricpropertiesofthecompositesofferroelectricceramicandpolyvinylchloride |
| first_indexed |
2025-07-08T18:26:09Z |
| last_indexed |
2025-07-08T18:26:09Z |
| _version_ |
1837104283081768960 |
| fulltext |
Condensed Matter Physics, 2003, Vol. 6, No. 2(34), pp. 307–313
Dielectric and pyroelectric properties of
the composites of ferroelectric ceramic
and poly(vinyl chloride)
M.Olszowy
Institute of Physics, University of Zielona Góra,
4a Szafrana Str., 65–516 Zielona Góra, Poland
Received October 24, 2002, in final form April 14, 2003
The dielectric and pyroelectric properties of lead zirconate titanate/poly(vi-
nyl chloride) [PZT/PVC] and barium titanate/poly(vinyl chloride) [BaTiO3/
PVC] composites were studied. Flexible composites were fabricated in the
thin films form (200−400 µm) by hot-pressed method. Powders of PZT or
BaTiO3 in the shape of 6 75 µm ceramics particles were dispersed in a
PVC matrix, providing composites with 0−3 connectivity. Distribution of the
ceramic particles in the polymer phase was examined by scanning elec-
tron microscopy. The analysis of the thermally stimulated currents (TSC)
have also been done. The changes of dielectric and pyroelectric data on
composites with different contents of ceramics up to 40% volume were in-
vestigated. The dielectric constants were measured in the frequency range
from 600 Hz to 6 MHz at room temperature. The pyroelectric coefficient for
BaTiO3/PVC composite at 343 K is about 35 µC/m2K which is higher than
that of β-PVDF (10 µC/m2K).
Key words: pyroelectric composite, dielectric properties, pyroelectric
properties, PZT/PVC, BaTiO3/PVC
PACS: 77.84.L, 77.70, 77.84.D
1. Introduction
Electroactive composites consisting of a ferroelectric ceramic in a polymer matrix
have gained much interest as compliant electromechanical or pyroelectric sensor.
The composite materials are mixtures that contain two phases: filler of ceramic and
matrix of polymer, where the fillers are included in the matrix in order to modify its
physical properties in a high range. As the fillers there are applied PZT, BaTiO3,
PbTiO3 ceramics, and the mentioned ceramics with different dopings as well [1].
Ferroelectric ceramic/polymer composites with 0–3 connectivity pattern owe their
popularity to the easy fabrication procedure which allows for mass production at a
relatively low cost [2].
c© M.Olszowy 307
M.Olszowy
The obtained composites 0–3 connectivity would exhibit the pyroelectric prop-
erties of ceramics and flexibility, strength and lightness of the polymer. The char-
acteristics of the grains of the ceramic powder in these composites also cause their
practical relevance. This is because the properties of ceramics depend not only on the
composition and their crystal structure but also on the microstructure morphology
including grain size, grain boundaries, pores, crystallinity, micro-cracks, etc. [2].
The electroactivity of ceramic/polymer composites has been reviewed by Das-
Gupta [2,3] who also significantly contributed to the knowledge of dielectric and
pyroelectric properties of the composites. Recently, the authors [4,5] discussed the
pyroelectric properties of the composites.
In this paper, we will describe dielectric and pyroelectric properties of PZT/PVC
and BaTiO3/PVC composites of 0–3 connectivity prepared of local components fab-
ricated in our laboratories. The dielectric characteristics we studied are important in
determining the figures of merit (p/ε) and the operation temperature range of pyro-
electric composites. Distribution of the ceramic grain and size grain in the polymer
phase was inspected by the scanning electron microscopy.
2. Sample preparation and experimental technique
The 0–3 composites reported in the paper were prepared by hot-pressing
(3.2 MPa pressure at ∼300 K has been applied) of the powder mixture and cooled to
room temperature under pressure at a rate of 8 K/min. The fine powders of PZT or
BaTiO3 in the shape of 6 75 µm ceramics grains were dispersed in suspension PVC.
Distribution of the ceramic grains in the PVC matrix and of the grains size was
examined by the scanning electron microscopy (SEM). As a result of vacuum evap-
oration on both sides of flexible polymer and composite sample films 200–400 µm
thick circular gold electrodes of 10 mm diameter have been gained. The dielectric and
pyroelectric properties of composites with different content of ceramics were investi-
gated. Dielectric constants and tan δ were studied by using computer aided hp–4192
ALF impedance analyzer in the frequency range from 600 Hz to 6 MHz at room
temperature. The sample has been polarized at Tp = 373 K for tp = 0.5 h in an DC
electrical field Ep = 1−4 MV/m. Pyroelectric current and thermally stimulated cur-
rents (TSC) have been measured at the constant heating rate of β = 2.6 K/min for
short-circuited samples. Pyroelectric measurements were performed on composites
using a quasi-static method. The pyroelectric coefficient is calculated from formula
p = I/Aβ, where I is the pyrocurrent and A is the electrode surface.
3. Results and discussion
The PZT/PVC and BaTiO3/PVC composites with different contents of ceram-
ics 0–40% were prepared. An admixture of the PZT or BaTiO3 added to the PVC
brings a change of the dielectric and electro-active properties of the polymer which
determine the pyroelectricity of the material. Figure 1 shows the variation of dielec-
tric constant ε with ceramics volume ratio at the room temperature. The measured
308
Dielectric and pyroelectric properties of the composites
0
5
10
15
20
25
30
35
40
45
50
0 10 20 30 40 50
Ceramic volume fraction (%)
εεεε
PZT/PVC
BaTiO3/PVC
Figure 1. Dielectric constant as a func-
tion of ceramics volume fraction at
1 kHz. The dashed curves with N and
4 are calculated with Lichtenecker mix-
ing rule and apply to fillers PZT and
BaTiO3, respectively.
value of ε for a pure PVC is equal to
3.7. When the volume fraction of the
ceramics in PVC increases, the ε at-
tains the magnitude of 29.5 and 36.2 for
PZT/PVC and BaTiO3/PVC, respec-
tively. The lower magnitude of the ex-
perimental values for a higher ceramics
content, in comparison with the predict-
ed results based on the Lichtenecker rule
[1], may be due to the presence of iso-
lated pores. The presence of the pores
being visible in the SEM picture of com-
posites (figure 2) in the shape of dark
stains. The dimension particles of ce-
ramics (bright objects having irregular
shapes) is not higher than 75 µm.
(a) (b)
Figure 2. SEM picture of the microstructure of (a) PZT/PVC and (b)
BaTiO3/PVC composites (with 30 vol% filler) taken at magnifications of ×180
and ×300, respectively.
Figure 3 shows the dielectric constant ε′ behaviour for the PVC and the com-
posites with temperature measured at 1 kHz. The values ε′ of the composites lay
between the values for the polymer and the values for the ceramics as expected. The
increment in dielectric constant for higher temperatures for BaTiO3/PVC is due to
the approach of the Curie temperature (Tc) of BaTiO3 which occurs at 393 K. Fre-
quency variations in the dielectric constant and tan δ of the investigated composites
PZT/PVC and BaTiO3/PVC, measured at room temperature, are given in figure 4.
The dielectric losses for a higher frequency of the composites are lower than those of
the polymer. The experiment revealed a relaxation process in the composites (both
309
M.Olszowy
in PZT/PVC and BaTiO3/PVC) with a maximum at ≈ 150 kHz. The dielectric
absorption is dominated by the polymer. The tan δ curves show an increment near
1 MHz which is probably due to the β relaxation of polymer.
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Figure 3. Temperature dependence of the dielectric constant ε
′ for the composites
with different ceramics contents.
0
5
10
15
20
25
30
35
1E+02 1E+03 1E+04 1E+05 1E+06 1E+07
εεεε D
0% 10% 20%
30% 40%
0
5
10
15
20
25
30
35
40
1E+02 1E+03 1E+04 1E+05 1E+06 1E+07
εεεε E
0% 10%
20% 30%
40%
0,00
0,05
0,10
0,15
0,20
0,25
1E+02 1E+03 1E+04 1E+05 1E+06 1E+07
Frequency [Hz]
F GH
δ δδδ
0% 10%
30% 40%
0,00
0,05
0,10
0,15
0,20
0,25
1E+02 1E+03 1E+04 1E+05 1E+06 1E+07
Frequency [Hz]
I JK
δ δδδ
0% 20%
30% 40%
(a) (b)
Figure 4. Frequency dependence of the dielectric constant ε
′ and tan δ for
PZT/PVC (a) and BaTiO3/PVC (b) composites.
The fragment of TSC thermograms of polarized films are characterized by the
pure PVC and BaTiO3/PVC composites of different value current density peaks
(figure 5). The thermogram of a PVC (curve 0%) as α peak at ≈ 350 K is shown
310
Dielectric and pyroelectric properties of the composites
0
2
4
6
8
10
12
14
303 313 323 333 343 353 363
Temperature (K)
j (
µ µµµA
/m
2 )
0% 10%
20% 30%
40%
0,01
0,1
1
10
100
1000
0 20 40 60 80 100
Ceramic volume fraction (%)
p
( µµ µµ
C
/m
2 K
)
0
0,5
1
1,5
2
2,5
3
FO
M
( µµ µµ
C
/m
2 K
)
p: PZT/PVC
p: BaTiO3/PVC
FOM: PZT/PVC
FOM: BaTiO3/PVC
Figure 5. TSC thermograms for
BaTiO3/PVC composites with dif-
ferent BaTiO3 contents. Conditions:
Ep = 4 MV/m, Tp = 373 K, tp = 0.5 h.
Figure 6. The depedence of the py-
roelectric coefficients and pyroelectric
Figure Of Merit (FOM) on the ceram-
ics powder content.
as well. This indicates that the TSC α peak of polymer electrets is mainly due
to the reorientation of dipolar main-chain segments [6]. Note that the location of
the α peak corresponds to the glass-rubber transition of PVC-unplasticized. A high
increase of current peaks of TSC of BaTiO3/PVC is observed when concentration
of BaTiO3 rises in the composites. Temperature positions of those peaks are not
changed. Moreover, the heights of these peaks depend on polarizing temperature
and polarizing field. A similar effect is observed in PZT/PVC composites [7]. The
increase of the electric charges, defined by TSC-peaks areas, as a result of admixing
of a polymer by ferroelectric ceramics, profitably effects the electroactive properties
of the composites. The increment in current density for higher temperatures for a
composite is due to the approach of the Tc temperature.
Dependence of pyroelectric coefficient p and pyroelectric Figure Of Merit (FOM)
on the ceramics volume fraction at 343 K is shown in figure 6.
For PVC, the measured value of p is 0.08 µC/m2K. The dielectric constant was
found to be equal to 3.7 and, thus, the pyroelectric FOM = p/ε was 0.02 µC/m2K.
With the growth of ceramics powder content value p increases, too. For a ceramic
volume fraction 40%, the value p for PZT/PVC and BaTiO3/PVC reaches about
15 µC/m2K and 35 µC/m2K, respectively. The measured pyroelectric coefficients
of the composites are higher than the coefficient of β-PVDF (10 µC/m2K) [8]. The
FOM achieves maximum value for concentrations of ceramics about 20% and it is
higher than that of the pure ceramics. The measured p and FOM of the compos-
ites are comparable with those parameters for other ferroelectric ceramic/polymer
composites consisting of PZT or BaTiO3 ceramic [1,2].
4. Conclusions
The dielectric and pyroelectric properties of 0–3 PZT/PVC and BaTiO3/PVC
composites as a function of the volume fraction of the ceramic were investigated. PZT
311
M.Olszowy
and BaTiO3 ceramics significantly modify their properties. Lower values of dielectric
constant for higher ceramics volume fraction could be attributed to the presence of
isolated pores. The pyroelectric activity increases with a growth of content of the
ceramics in the composite. The pyroelectric coefficients of our samples are higher
than the parameters for β-PVDF. The achieved pyroelectric FOM is higher than that
of the pure ceramics. Furthermore, an increase of the FOM value in the obtained
composites at higher temperatures, given by the ratio p/ε, is conditioned by the
value ε that is practically not changed within a temperature range 300–350 K.
References
1. Nalwa H.S. Ferroelectric Polymers. New York, Basel, Hong Kong, Marcel Dekker Inc.,
1995.
2. Dias C.J., Das-Gupta D.K. Ferroelectric Ceramic/Polymer Composite Electrets. – In:
Electrets. (Ed. Gerhard-Multhaupt R.) Morgan Hill, CA, Laplacian Press, 1999, vol. 2,
p. 193.
3. Dias C.J., Das-Gupta D.K. // IEEE Trans. Dielectric Electr. Insul., 1996, vol. 3, p. 706.
4. Lang S.B., Das-Gupta D.K. // Ferroelectrics Rev., 2000, vol. 2, p. 217.
5. Hilczer B., Kulek J., Markiewicz E., Kosec M. // Ferroelectrics, 2002, vol. 267, p. 277.
6. van Turnhout J. Thermally Stimulated Discharge of Polymer Electrets. Amsterdam,
Elsevier Sci. Publ. Co., 1975.
7. Olszowy M. Piezoelectric and Pyroelectric Behaviour in PVC/PZT Composite Thin
Films. – In: Proc. 6th Int. Conf. on Dielectric and Related Phenomena DRP 2000,
Spala, 6–10 September 2000, p. 95.
8. Sakamoto, W.K., Kanada D.H.F., Das-Gupta D.K. // Math. Res. Innovat., 2002, vol. 5,
p. 257.
312
Dielectric and pyroelectric properties of the composites
Діелектричні і піроелектричні властивості
композитів сегнетоелектричної кераміки і
полі(вінил хлориду)
М.Ольшови
Інститут фізики, Університет м. Зєльона Ґура
Польща, 65–516 Зєльона Ґура, вул. Шафрана, 4а
Отримано 24 жовтня 2002 р., в остаточному вигляді –
14 квітня 2003 р.
Досліджено діелектричні і піроелектричні властивості композитів
цирконату свинцю/полі(вінил хлориду) та титанату барію/полі(вінил
хлориду). Еластичні композити виготовлено у вигляді тонких плі-
вок (200−400 мкм) методом гарячого пресування. Порошки PZT
та BaTiO3 у вигляді керамічних частинок з діаметром меншим за
0.75 мкм розпилено в матриці полівінилхлориду, при чому утвори-
лися композити зі зв’язністю 0−3. Розподіл керамічних частинок
у полімерній фазі досліджено за допомогою електронного скану-
ючого мікроскопа. Також проведено аналіз термічно стимульова-
них струмів. Досліджено зміни діелектричних і піроелектричних ха-
рактеристик композитів при зміні вмісту кераміки до 40%. Діелек-
тричні сталі виміряні у частотному діапазоні від 600 Гц до 6 МГц
при кімнатній температурі. Піроелектричний коефіцієнт композиту
BaTiO3/PVC при 343 K складає 35 мкКл/м2K, що вище, ніж у β-PVDF
(10 мкКл/м2K)
Ключові слова: піроелектричний композит, діелектричні
властивості, піроелектричні властивості, PZT/PVC, BaTiO3/PVC
PACS: 77.84.L, 77.70, 77.84.D
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