Reduced curing kinetic energy and enhanced thermal resistance
of phthalonitrile resins modified with inorganic particles
Polymer Science & Materials, Chemical
Engineering College, Dalian University of
Technology, Dalian 116024, China
State Key Laboratory of Fine Chemicals,
Dalian University of Technology, Dalian
Aerospace Research Institute of Materials &
Processing Technology, Beijing 100076, China
Xigao Jian, Polymer Science & Materials,
Chemical Engineering College, Dalian
University of Technology, Dalian 116024,
Key Laboratory Foundation of State Key Lab-
oratory of Organic‐Inorganic Composites,
Grant/Award Number: oic‐201701005; Fun-
damental Research Funds for the Central Uni-
versities, Grant/Award Number:
DUT16RC(3)056; National Key Research and
Development Program of China, Grant/Award
The effects of inorganic particles such as Al
C on the solidification kinetics and heat
resistance of phthalonitrile resin were investigated. The properties of the blends and the cured
products were tested by rheometer, differential scanning calorimetry, Fourier transform infrared
spectroscopy, and thermogravimetric analysis. The results revealed that B
C and Al
particles could prolong the gel time of phthalonitrile resin and broaden the processing window.
The curing kinetic analysis showed that the presence of the particles could significantly reduce
the curing activation energy of phthalonitrile resins by 72.38 kJ/mol down to 43.03 kJ/mol.
Meanwhile, the heat resistance of the phthalonitrile resin was improved. Among them, the blend
system combined with 30% B
C showed prominent thermoresistance. And while the T
loss temperature was 600°C, char yield at 1000°C was higher than 86% under nitrogen
atmosphere; while the T
weight loss temperature was 581°C, char yield at 1000°C was higher
than 80% under air atmosphere. Hence, the resulting resins were good candidate matrix of
high‐temperature structural composites.
curing kinetics, heat resistance, inorganic particles, phthalonitrile
High modulus, strength, and heat resistance materials and their com-
posites were required to satisfy the rapidly developing aerospace
vehicles such as reentry modules and space shuttles.
progress of novel high‐performance materials has been achieved in
the last few decades.
As one of them, the phthalonitrile resins
were developed by the United States Naval Research Labora-
tory more than 30 years ago.
Because of exceptional properties
such as outstanding thermal and thermooxidative stability, excellent
mechanical properties, fire resistant performance, and good moisture
property, the phthalonitrile resins
and their composites are supposed
to be the most suitable materials for those harsh application condi-
However, as the Mach numbers of ultrahigh‐speed aircrafts
are continuously increasing, novel modification on PN should be devel-
oped to meet the requirements.
Recently, introducing the inorganic particles into the composites
has drawn much more attention.
Because they could render the
resins' outstanding advantages of cost‐effective processibility,
enhanced stiffness, strength, and high mechanical properties. Different
kinds of inorganic particles, such as boron carbide (B
), silicon carbide (SiC), and aluminum oxide (Al
been widely used as filler in different kinds of polymeric matrices.
Wang et al
prepared 2 types of composites based on PN rein-
forced with SiC and Si
, respectively. The results showed that the
mechanical and thermal properties were sharply elevated caused by
the addition of inorganic particles. Because of the requirements of
high‐speed aircraft, it is urgent to further improve the heat resistance,
modulus, and strength of the material. Jiang
selected as the additive
for the modification of a phenol formaldehyde (PF), showing excellent
thermophysical properties. Wang
as the coat of quartz
fiber‐reinforced methyl silicone resin composites; mechanical property
was higher than the uncoated fiber composites at 600°C. Many studies
have proved that inorganic particles reveal remarkable thermostability
which can also become the uniform of composites at high temperature.
Besides, as far as we know, there are few reports about the effect of
C and Al
into the PN to improve the thermal stability
and mechanical properties.
Received: 31 October 2017 Revised: 18 January 2018 Accepted: 21 February 2018
1922 Copyright © 2018 John Wiley & Sons, Ltd. Polym Adv Technol. 2018;29:1922–1929.wileyonlinelibrary.com/journal/pat