Angewandte Chemie International Edition,
Год журнала:
2023,
Номер
62(52)
Опубликована: Ноя. 8, 2023
A
novel
in
situ
chemical
upcycling
strategy
for
plastic
waste
is
proposed
by
the
customized
diphenylacetylene
monomer
with
dual
photo-response.
That
is,
reactive
monomers
are
inserted
into
macromolecular
chain
of
polyethylene
terephthalate
(PET)
plastics/fibers
through
one-pot
transesterification
slight-depolymerization
and
re-polymerization.
On
one
hand,
group
absorbs
short-wave
high-energy
UV
rays
then
releases
long-wave
low-energy
harmless
fluorescence.
other
UV-induced
photo-crosslinking
reaction
among
groups
produces
extended
π-conjugated
structure,
resulting
a
red-shift
(due
to
decreased
HOMO-LUMO
separation)
absorption
band
locked
crosslink
points
between
PET
chains.
Therefore,
increasing
exposure
time,
upcycled
plastics
exhibit
reverse
enhanced
resistance
mechanical
strength
(superior
original
performance),
instead
serious
UV-photodegradation
damaged
performance.
This
at
oligomer-scale
not
only
provides
new
idea
traditional
recycling,
but
also
solves
common
problem
gradual
degradation
polymer
performance
during
use.
Nature Communications,
Год журнала:
2024,
Номер
15(1)
Опубликована: Июнь 7, 2024
The
regulation
of
topological
structure
covalent
adaptable
networks
(CANs)
remains
a
challenge
for
epoxy
CANs.
Here,
we
report
strategy
to
develop
strong
and
tough
supramolecular
thermosets
with
rapid
reprocessability
room-temperature
closed-loop
recyclability.
These
were
constructed
from
vanillin-based
hyperbranched
resin
(VanEHBP)
through
the
introduction
intermolecular
hydrogen
bonds
dual
dynamic
bonds,
as
well
formation
intramolecular
cavities.
structures
confer
remarkable
energy
dissipation
capability
thermosets,
leading
high
toughness
strength.
Due
imine
exchange
reversible
noncovalent
crosslinks,
can
be
rapidly
effectively
reprocessed
at
120
°C
within
30
s.
Importantly,
efficiently
depolymerized
room
temperature,
recovered
materials
retain
structural
integrity
mechanical
properties
original
samples.
This
may
employed
design
tough,
recyclable
practical
applications.
Recycling,
Год журнала:
2024,
Номер
9(3), С. 37 - 37
Опубликована: Май 6, 2024
This
review
article
gathers
the
most
recent
recycling
technologies
for
thermoset
and
thermoplastic
polymers.
Results
about
existing
experimental
procedures
their
effectiveness
are
presented.
For
polymers,
focuses
mainly
on
fibre-reinforced
polymer
composites,
with
an
emphasis
epoxy-based
systems
carbon/glass
fibres
as
reinforcement,
due
to
environmental
concerns
of
end-of-life
management.
Thermal
processes
(fluidised
bed,
pyrolysis)
chemical
(different
types
solvolysis)
discussed.
The
combined
(microwave,
steam,
ultrasonic
assisted
techniques)
extraordinary
attempts
(electrochemical,
biological,
ionic
liquids)
analysed.
Mechanical
that
leads
downgrading
materials
is
excluded.
Insights
also
given
upcycling
methodologies
have
been
implemented
until
now
reuse
fibres.
As
state-of-the-art
approach
common
matrices
presented,
together
appropriate
additivation
matrix
upcycling.
Mechanical,
chemical,
enzymatic
described,
among
others.
use
composites
quite
new,
thus,
achievements
With
all
above
information,
this
extensive
can
serve
a
guide
educational
purposes,
targeting
students
technicians
in
polymers
recycling.
Advanced Materials,
Год журнала:
2025,
Номер
unknown
Опубликована: Янв. 8, 2025
Abstract
Polymeric
materials
featuring
excellent
flame
retardancy
are
essential
for
applications
requiring
high
levels
of
fire
safety,
while
those
based
on
biopolymers
highly
favored
due
to
their
eco‐friendly
nature,
sustainable
characteristics,
and
abundant
availability.
This
review
first
outlines
the
pyrolysis
behaviors
biopolymers,
with
particular
emphasis
naturally
occurring
ones
derived
from
non‐food
sources
such
as
cellulose,
chitin/chitosan,
alginate,
lignin.
Then,
strategies
chemical
modifications
flame‐retardant
purposes
through
covalent,
ionic,
coordination
bonds
presented
compared.
The
is
placed
advanced
methods
introducing
biopolymer‐based
retardants
into
polymeric
matrices
fabricating
materials.
Finally,
challenges
sustaining
current
momentum
in
utilization
further
discussed.
ACS Sustainable Chemistry & Engineering,
Год журнала:
2023,
Номер
11(39), С. 14445 - 14456
Опубликована: Сен. 22, 2023
Vitrimers
have
promise
as
adaptable
materials
capable
of
self-healing,
shape
reconfigurability,
and
remoldability
due
to
dynamic
covalent
reactions
occurring
above
their
transition
temperatures;
however,
relatively
poor
mechanical
properties,
particularly
compared
commercially
available
thermosets,
limited
further
application
in
diverse
industries.
Herein,
we
demonstrate
a
rigid-flexible
integrated
strategy
for
fabricating
robust
epoxy
vitrimers
(EVs)
with
superb
properties
comparable
those
conventional
thermosets.
The
rigid
aromatic
Schiff
base
moiety
flexible
siloxane
spacer
increased
the
network
rigidity
molecular
weight
between
cross-links,
endowing
EVs
high
strength,
ultratoughness,
rapid
exchange
imine
bonds.
EV
displayed
rarely
reported
ultrahigh
impact
strength
61.8
kJ·m–2
realized
recyclability
thermosetting
resin
through
physical
reprocessing
chemical
recycling.
Furthermore,
it
broke
restriction
on
plasticity
greatly
by
permanent
provided
solution
inherent
contradictions
facile
malleability,
repaired
deficiency
brittleness
flammability
toward
resins
without
any
use
flame-retardant
elements,
such
halogens
phosphorus.
based
this
enormously
broaden
field
application,
is
great
significance
recycling
damaged,
aged,
or
discarded
resin-based
well
resource
conservation
environmental
protection.
