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should disperse well in the non-polar PP based on the compatibility
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dispersion in PP (Fig. 10).
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3.3. Thermal stability
All synthesized PCIs exhibited thermal stability up to 330 ꢀC,
which is in agreement with earlier studies. Decomposition of the
pigments occurs in two stages. First, degradation in mass occurs in
the range of 330e400 ꢀC, which represents the decomposition of
the N-substituent. The second stage occurs after 700 ꢀC and
represents the oxidation of the central perylene core in air. Deriv-
ative P1 exhibits thermal stability up to 400 ꢀC, whereas P2 was the
least thermally stable derivative and decomposed at 330 ꢀC.
[9] Fridolin B. Inventor ciba speciality, assignee. IR reflective pigment composi-
tion; 2006. United States.
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[11] Oh SH, Kim BG, Yun SJ, Maheswara M, Kim K, Do JY. The synthesis of
symmetric and asymmetric perylene derivatives and their optical properties.
Dyes and Pigments 2010;85(1e2):37e42.
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Coatings 1997;31(1e2):43e9.
[13] Sapagovas VJ, Gaidelis V, Kovalevskij V, Undzenas A. 3,4,9,10-
Perylenetetracarboxylic acid derivatives and their photophysical properties.
Dyes and Pigments 2006;71(3):178e87.
[14] Koyuncu S, Kus M, Demic S, Kaya I, Ozdemir E, Icli S. Electrochemical and
optical properties of novel donon-acceptor thiophene-perylene -thiophene
polymers. Journal of Polymer Science Part A: Polymer Chemistry 2008;46(6):
1974e89.
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tophysical and electrochemical characterizations. Dyes and Pigments 2009;
83(3):297e303.
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Jobic Stephane. Investigation of the origin of the empirical relationship
between refractive index and density on the basis of first principles calcula-
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43(7):2246e51.
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1912e8.
4. Conclusions
PTCA, which is commonly used as a starting material in the
synthesis of various PCIs, exhibited significantly higher reflectance
in the NIR region than any of the PCIs synthesized from it in this
study. Significant variation in the NIR reflectance of the PCIs
synthesized in this study was observed, despite the samples
exhibiting similar ranges of particle size (3e7
mm). All of the
synthesized PCIs were thermally stability up to 330 ꢀC. No direct
correlation between the nature of the N-substituent and reflec-
tance in the NIR region could be established on the basis of this
limited study. However, this study is significant due to the estab-
lishment of a potential relationship between the nature of the
substituent and the expected reflectance in the NIR region, pending
further computational studies on these derivatives.
Acknowledgments
The authors would like to acknowledge the School of Applied
Sciences, RMIT for providing the instruments used in this research.
B. K gratefully acknowledges AutoCRC for providing financial
support for this research project.
[18] Papini M. Analysis of the reflectance of polymers in the near -and mid-
infrared regions. Journal of Quantitative Spectroscopy and Radiative Trans-
fer 1997;57(2):265e74.
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(dicarboximide).
A computational quantum chemistry study with insight
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