New Journal of Chemistry,
Год журнала:
2024,
Номер
unknown
Опубликована: Янв. 1, 2024
This
paper
provides
an
effective
method
for
lignin
utilization
to
prepare
bio-based
phenolic
foams
with
improved
flame
retardancy
and
mechanical
properties.
Polymer,
Год журнала:
2024,
Номер
308, С. 127361 - 127361
Опубликована: Июль 5, 2024
This
study
focuses
on
developing
environmentally
friendly
plasticized
poly(lactide)
(PLA)
formulations
using
tartaric
acid
and
α-tocopherol
at
20
wt%.
The
extrusion
injection
molding
processes
demonstrated
the
industrial
applicability
of
these
plasticizers.
Mechanical
tests
revealed
positive
results
for
tartrate-based
plasticizers,
with
elongation
break
surpassing
220
%,
while
succinate
achieved
170
%.
However,
acetate
showed
limited
PLA
plasticization.
Field
emission
scanning
electron
microscopy
confirmed
plasticization
in
fractured
surfaces.
Thermal
analysis
indicated
a
reduction
PLA's
glass
transition
temperature
(Tg)
from
60
°C
to
around
30
underscoring
tartrates'
exceptional
efficiency.
cold
crystallization
(Tcc)
decreased
all
samples
due
enhanced
chain
mobility.
Thermomechanical
dimensional
shrinkage,
dimethyl
tartrate
(DMT)
causing
less
pronounced
effects.
Generally,
tartrates
yielded
superior
properties,
attributed
their
lower
molecular
weight
compared
α-tocopherol-derived
Notably,
plasticizers
employed
are
an
eco-friendly
approach
improve
processability
enhancing
ductile
properties.
Against
the
background
of
practical
application
requirements
and
sustainable
development,
achieving
an
equilibrium
between
crystallization,
mechanical
properties
flame
retardancy
polylactide
(PLA)
with
a
green
strategy
has
been
challenge.
Additionally,
previous
work
lacked
to
explore
structure-activity
relationship.
Herein,
four
lignin-derived
phosphonamides
containing
P-C
P-O-C
bonds
were
synthesized
used
fabricate
PLA
composites.
The
crystallization
behaviors,
composites
systematically
compared,
influence
structure
on
flame-retardant
mechanism
was
emphasized.
DSC
results
showed
that
these
act
as
nucleating
agents
they
significantly
improved
capacity
PLA.
Interestingly,
are
more
effective
than
in
accelerating
rate,
increasing
nucleation
density
reducing
crystal
size.
Beyond
that,
maintain
outstanding
properties,
exhibited
significant
improvement.
6
wt%
fulfilled
UL-94
V-0
ratings
enhanced
LOI
values.
Phosphonamides
endow
higher
efficiency,
while
enable
Flame
retardant
analysis
suggests
primarily
vapor
phase,
condensed
phase.
is
realized
by
synergistic
effects
drop
away,
free
radical
trapping,
dilutive
influence,
residual
char.
In
summary,
this
research
provides
for
fabrication
overall
performance,
which
exhibits
broad
prospect
industry.
International Journal of Polymer Analysis and Characterization,
Год журнала:
2025,
Номер
unknown, С. 1 - 16
Опубликована: Янв. 14, 2025
Casein-based
rigid
polyurethane
foam
(RPUF)
with
different
ratios
of
starch
and
sepiolite
were
prepared
by
a
one-step
process.
Thermogravimetric
analysis,
CONE
scanning
electron
microscopy
limiting
oxygen
index
(LOI)
vertical
combustion
mechanical
property
analysis
used
to
explore
the
thermal
stability,
flame
retardancy,
compressive
properties
modified
RPUFs,
respectively.
The
results
showed
that
initial
decomposition
temperature
activation
energy
(E)
RPUF-C5ST2SE3
(5
g
casein,
2
starch,
3
sepiolite)
highest.
Under
condition
radiant
flux
50
kW/m2,
peak
heat
release
rate
(PHRR),
total
(THR),
smoke
production
(PSPR),
(TSR)
reduced
35.92%,
10.83%,
36.67%,
18.20%,
respectively,
compared
RPUF
without
retardant.
By
analyzing
carbon
residue,
it
was
found
had
highest
residue
its
morphology
relatively
intact.
In
addition,
LOI
UL-94
rating
V-0.
At
same
time,
also
best
property.
present
experimental
can
provide
useful
reference
for
future
retardant
studies.
Journal of Polymer Science,
Год журнала:
2025,
Номер
unknown
Опубликована: Фев. 12, 2025
ABSTRACT
A
derivative
based
on
9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide
and
maleimide
units
with
terminal
hydroxyl
group
(DH)
was
synthesized
incorporated
in
poly(lactic
acid)
(PLA).
The
properties
mechanism
of
PLA/DH
composites
were
investigated.
results
showed
that
PLA
under
10
wt%
DH
load
achieved
vertical
combustion
test
(UL‐94)
V‐0
rating
an
increased
limiting
oxygen
index
(LOI)
27.2%
a
15.8%
decrease
peak
heat
release
rate.
prominent
flame
retardant
efficiency
attributed
to
its
excellent
inhibition
diluting
effects
gaseous
phase
as
well
certain
cross‐linked
structure
the
condensed
phase.
Specifically,
elongation
at
break
PLA/DH‐7.5
by
17.6%
comparison
pure
PLA.
displayed
enhanced
interaction
good
compatibility
PLA,
thus
endowing
comprehensive
performances
As
result,
combination
phosphaphenanthrene
provides
facile
effective
method
improve
retardancy
mechanical
In
order
to
improve
the
specimens'
flame-retardant
qualities,
ethyl
orthosilicate
was
impregnated
into
them
using
a
combination
of
delignification
process
and
in
situ
growing
approach.
Lignification
has
been
demonstrated
increase
cellular
gap
specimen
maximize
impregnation
orthosilicate.
Moreover,
growth
method
results
specimens
containing
silica
manufactured
from
orthosilicate,
thereby
forming
composite
material
with
enhanced
properties.
The
examination
changes
properties
before
after
modification
conducted
FTIR
spectroscopy,
XRD,
XPS,
SEM,
other
experimental
techniques.
modified
exhibited
higher
comparison
untreated
specimens.
Furthermore,
mechanical
properties,
characterized
by
an
augmented
compressive
strength
34.9
MPa
strength-to-weight
ratio
158
MPa·cm·g-1,
that
did
not
undergo
process.
experiments
show
proposed
green
technology
provides
new
for
producing
composites
could
significantly
qualities
wood.