ACS Catalysis,
Journal Year:
2024,
Volume and Issue:
14(16), P. 12437 - 12453
Published: Aug. 5, 2024
Synthetic
polymers
play
an
indispensable
role
in
modern
society,
finding
applications
across
various
sectors
ranging
from
packaging,
textiles,
and
consumer
products
to
construction,
electronics,
industrial
machinery.
Commodity
plastics
are
cheap
produce,
widely
available,
versatile
meet
diverse
application
needs.
As
a
result,
millions
of
metric
tons
manufactured
annually.
However,
current
approaches
for
the
chemical
recycling
postconsumer
plastic
waste,
primarily
based
on
pyrolysis,
lag
efficiency
compared
their
production
methods.
In
recent
years,
significant
research
has
focused
developing
milder,
economically
viable
methods
commodity
plastics,
which
involves
converting
waste
back
into
monomers
or
transforming
it
other
valuable
chemicals.
This
Perspective
examines
both
cutting-edge
laboratory-scale
contributing
advancements
field
recycling.
Chemical Science,
Journal Year:
2023,
Volume and Issue:
15(3), P. 832 - 853
Published: Dec. 5, 2023
Insight
into
the
thermodynamics
and
kinetics
of
depolymerization
to
understand
barriers
that
prevent
effective
monomer
regeneration
from
vinyl
polymers,
an
exploration
overcoming
these
limitations.
JACS Au,
Journal Year:
2023,
Volume and Issue:
3(9), P. 2436 - 2450
Published: Aug. 23, 2023
Over
the
past
couple
of
decades,
polymers
that
depolymerize
end-to-end
upon
cleavage
their
backbone
or
activation
a
terminal
functional
group,
sometimes
referred
to
as
"self-immolative"
polymers,
have
been
attracting
increasing
attention.
They
are
growing
interest
in
context
enhancing
polymer
degradability
but
also
recycling
they
allow
monomers
be
regenerated
controlled
manner
under
mild
conditions.
Furthermore,
highly
promising
for
applications
smart
materials
due
ability
provide
an
amplified
response
specific
signal,
single
sensing
event
is
translated
into
generation
many
small
molecules
through
cascade
reactions.
From
chemistry
perspective,
depolymerization
relies
on
principles
self-immolative
linkers
and
ceiling
temperature
(Tc).
In
this
article,
we
will
introduce
key
chemical
concepts
foundations
field
then
our
perspective
recent
exciting
developments.
For
example,
over
few
years,
new
depolymerizable
backbones,
including
polyacetals,
polydisulfides,
polyesters,
polythioesters,
polyalkenamers,
developed,
while
modern
approaches
conventional
backbones
such
polymethacrylates
introduced.
Progress
has
made
topological
evolution
systems,
introduction
fully
block
copolymers,
hyperbranched
networks.
precision
sequence-defined
oligomers
synthesized
studied
data
storage
encryption.
Finally,
perspectives
future
opportunities
challenges
discussed.
Chem,
Journal Year:
2023,
Volume and Issue:
10(1), P. 388 - 401
Published: Oct. 26, 2023
Depolymerization
of
polymers
synthesized
by
reversible
deactivation
radical
polymerization
(RDRP)
has
recently
emerged
as
a
promising
chemical
recycling
method
for
circular
economy.
However,
current
depolymerization
reactions
are
typically
uncontrolled
(i.e.,
molecular
weight
remains
unchanged),
thus
providing
no
handle
over
the
and
limiting
further
applications.
Herein,
we
report
controlled
addition-fragmentation
chain-transfer
(RAFT)
that
enables
gradual
decrease
in
weight,
resembling
reverse
process
polymerization.
The
key
to
our
strategy
is
enhance
chain
depropagation
employing
RAFT
agents
with
high
activity,
resulting
unzipping
polymer
chains
linear
time.
As
an
exemplary
application,
demonstrate
structural
characterization
various
copolymers
AB
diblock
versus
BA
statistical
gradient)
facilitating
sequential
release
monomers
from
end,
pushing
boundaries
unlocking
new
Angewandte Chemie International Edition,
Journal Year:
2023,
Volume and Issue:
62(45)
Published: Oct. 9, 2023
A
photocatalytic
RAFT-controlled
radical
depolymerization
method
is
introduced
for
precisely
conferring
temporal
control
under
visible
light
irradiation.
By
regulating
the
deactivation
of
depropagating
chains
and
suppressing
thermal
initiation,
an
excellent
was
enabled,
exemplified
by
several
consecutive
"on"
"off"
cycles.
Minimal,
if
any,
could
be
observed
during
dark
periods
while
polymer
chain-ends
efficiently
re-activated
continue
to
depropagate
upon
re-exposure
light.
Notably,
favoring
resulted
in
gradual
unzipping
a
stepwise
decrease
molecular
weight
over
time.
This
synthetic
approach
constitutes
simple
methodology
modulate
chemical
recycling
RAFT-synthesized
polymers
offering
invaluable
mechanistic
insights.
Green Chemistry,
Journal Year:
2024,
Volume and Issue:
26(5), P. 2384 - 2420
Published: Jan. 1, 2024
While
our
society
is
facing
the
challenge
of
accumulating
plastic
waste,
this
review
discusses
recent
advances
towards
polymer
circularity
with
an
emphasis
on
manipulations
monomer–polymer
equilibrium
to
create
chemically
recyclable
polymers.
Macromolecules,
Journal Year:
2024,
Volume and Issue:
57(7), P. 3131 - 3137
Published: March 25, 2024
In
this
report,
we
demonstrate
that
polymethacrylates
can
undergo
appreciable
depolymerization,
with
mild
conditions
and
without
reactive
end
groups,
using
ball-mill
grinding
(BMG).
For
instance,
the
important
commercial
polymer,
poly(methyl
methacrylate)
(PMMA)
underwent
up
to
41%
depolymerization
monomer
within
8
min
of
grinding.
We
explored
factors
influence
conversion
found
temperature
(heating
only
43
°C),
addition
a
small
amount
liquid
(μL
tert-butyl
alcohol),
ball
number/size
be
most
parameters.
also
applied
method
other
pendent
substituent
extent
depolymerization.
Addition
was
reverse
effects
were
observed
bulk
among
studied,
PMMA
had
lowest
in
one
highest
conversions
slurry.
Notably,
molecular
weight
residual
polymer
is
remarkably
low,
ca.
1
kDa,
demonstrating
excellent
degradation
performance
BMG.
Overall,
work
provides
mechanistic
insight
into
reactions
under
ball-milling
represents
an
step
expanding
BMG
as
tool
for
chemical
recycling
polymethacrylates.
