Journal of Applied Polymer Science,
Journal Year:
2025,
Volume and Issue:
unknown
Published: Feb. 18, 2025
ABSTRACT
Overheating
of
electronic
devices
reduces
lifespan
and
increases
safety
risks.
The
use
graphite
films
with
high
thermal
conductivity
to
enhance
dissipation
in
equipment
is
significant
importance.
This
study
used
urea‐choline
chloride
(UCC)
modify
polyimide
(PI)
from
two
different
monomer
systems,
which
were
then
graphitized
prepare
a
novel
film
conductivity.
direct
formation
hydrogen
bonds
between
poly(amic
acid)
(PAA)
UCC
facilitates
the
ordered
structure
during
imidization,
enhancing
graphitization
degree
thermodynamic
properties
PI
films.
results
indicate
that
increased
30%
over
59%
4,4′‐oxydianiline‐pyromellitic
dianhydride
(OPU)
system
80%
92%
4,4′‐diaminobenzoyltiphenylamine‐3,3′,4,4′‐biphenyl
tetracarboxylic
(DBU)
system.
Notably,
dianhydride‐3.5
wt%
(OPU35)
(DBU35)
exhibited
highest
their
respective
coefficients
45
742
W/m
K,
representing
200%
47.8%
improvements
pure
PI‐based
provides
new
material
for
heat
devices.
Applied Physics Letters,
Journal Year:
2025,
Volume and Issue:
126(5)
Published: Feb. 3, 2025
To
clarify
future
research
directions,
this
study
first
analyzes
the
heat
transfer
process
of
solar-thermal
conversion
and
then
reviews
phase
change
composites
for
high-efficiency
harnessing
solar
energy.
The
focus
is
on
enhancing
absorption
conduction
while
aiming
to
suppress
reflection,
radiation,
convection.
Most
advancements
have
concentrated
improving
thermal
conductivity,
reducing
aforementioned
unfavorable
processes
remains
less
explored.
In
current
research,
best
results
show
that
efficiency
has
approached
theoretical
limit
(100%),
a
typical
conductivity
reached
33.5
W/(m·K).
However,
further
enhancement
challenge,
highlighting
need
structural
modifications
grafting.
Other
factors
hindering
received
limited
attention
warrant
in-depth
investigation,
with
potential
reduce
reliance
fossil
fuels
contribute
environmental
sustainability.
Advanced Functional Materials,
Journal Year:
2024,
Volume and Issue:
unknown
Published: Dec. 9, 2024
Abstract
In
non‐metallic
atom‐doped
carbonaceous
materials,
the
disparity
in
electronegativity
between
doped
constituents
and
carbon
atoms
predetermines
bonding
topology
of
covalent
bonds
distribution
electron
density.
This,
consequently,
influences
polarization
transport
behavior
within
domain
electromagnetic
wave
attenuation
attributes
material.
However,
influence
formed
by
doping
with
weakly
electronegative
on
density
distribution,
effects,
remains
uncharted.
To
address
this
deficiency,
study
fabricates
a
porous
material
(NCP)
incorporates
boron‐doped
to
form
tunable
B─C
configurations
(B‐NCP).
By
modulating
configuration
proportion,
it
is
feasible
achieve
synergistic
optimization
conductive
loss
B‐NCP
specimen.
The
optimized
prototype
‐1200
sample
displays
exceptionally
efficient
absorption
capabilities
minimum
reflection
(RL
min
)
−52.03
dB
an
effective
bandwidth
(EAB)
5.36
GHz.
This
presents
conscientious
model
for
comprehending
mechanisms
associated
atom
carbon‐based
wave‐absorbing
materials.
