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.
Journal of the American Chemical Society,
Journal Year:
2023,
Volume and Issue:
145(39), P. 21146 - 21151
Published: Sept. 22, 2023
A
photocatalytic
ATRP
depolymerization
is
introduced
that
significantly
suppresses
the
reaction
temperature
from
170
to
100
°C
while
enabling
temporal
regulation.
In
presence
of
low-toxicity
iron-based
catalysts
and
under
visible
light
irradiation,
near-quantitative
monomer
recovery
could
be
achieved
(up
90%),
albeit
with
minimal
control.
By
employing
ppm
concentrations
either
FeCl2
or
FeCl3,
during
dark
periods
completely
eliminated,
thus
control
possibility
modulate
rate
by
simply
turning
"on"
"off".
Notably,
our
approach
allowed
preservation
end-group
fidelity
throughout
reaction,
carried
out
at
high
polymer
loadings
2M),
was
compatible
various
polymers
sources.
This
methodology
provides
a
facile,
environmentally
friendly,
temporally
regulated
route
chemically
recycle
ATRP-synthesized
polymers,
opening
door
for
further
opportunities.
Angewandte Chemie International Edition,
Journal Year:
2023,
Volume and Issue:
62(38)
Published: July 31, 2023
Although
controlled
radical
polymerization
is
an
excellent
tool
to
make
precision
polymeric
materials,
reversal
of
the
process
retrieve
starting
monomer
far
less
explored
despite
significance
chemical
recycling.
Here,
we
investigate
bulk
depolymerization
RAFT
and
ATRP-synthesized
polymers
under
identical
conditions.
RAFT-synthesized
undergo
a
relatively
low-temperature
solvent-free
back
thanks
partial
in
situ
transformation
end-group
macromonomer.
Instead,
can
only
depolymerize
at
significantly
higher
temperatures
(>350
°C)
through
random
backbone
scission.
To
aid
more
complete
even
lower
temperatures,
performed
facile
quantitative
modification
strategy
which
both
ATRP
end-groups
were
successfully
converted
macromonomers.
The
macromonomers
triggered
temperature
with
onset
150
°C
yielding
up
90
%
regeneration.
versatility
methodology
was
demonstrated
by
scalable
(≈10
g
polymer)
retrieving
84
intact
could
be
subsequently
used
for
further
polymerization.
This
work
presents
new
low-energy
approach
depolymerizing
creates
many
future
opportunities
as
high-yielding,
methods
are
sought.
Journal of the American Chemical Society,
Journal Year:
2024,
Volume and Issue:
146(9), P. 6217 - 6224
Published: Feb. 21, 2024
In
this
study,
we
present
an
efficient
approach
for
the
depolymerization
of
poly(methyl
methacrylate)
(PMMA)
copolymers
synthesized
via
conventional
radical
polymerization.
By
incorporating
low
mol
%
phthalimide
ester-containing
monomers
during
polymerization
process,
colorless
and
transparent
polymers
closely
resembling
unfunctionalized
PMMA
are
obtained,
which
can
achieve
>95%
reversion
to
methyl
methacrylate
(MMA).
Notably,
our
catalyst-free
bulk
method
exhibits
exceptional
efficiency,
even
high-molecular-weight
polymers,
including
ultrahigh-molecular-weight
(10
Angewandte Chemie International Edition,
Journal Year:
2024,
Volume and Issue:
63(19)
Published: March 11, 2024
Abstract
Photocatalytic
upcycling
and
depolymerization
of
vinyl
polymers
have
emerged
as
promising
strategies
to
combat
plastic
pollution
promote
a
circular
economy.
This
mini
review
critically
summarizes
current
developments
in
the
degradation
including
polystyrene
poly(meth)acrylates.
Of
these
material
classes,
polymethacrylates
possess
unique
possibility
undergo
photocatalytic
back
monomer
under
thermodynamically
favourable
conditions,
thus
presenting
significant
advantages
over
traditional
thermal
strategies.
Our
perspective
on
formidable
challenges
potential
future
directions
are
also
discussed.
European Polymer Journal,
Journal Year:
2024,
Volume and Issue:
211, P. 113001 - 113001
Published: March 30, 2024
Atom
transfer
radical
polymerization
(ATRP)
is
one
of
the
most
often
used
controlled
techniques.
It
employs
very
small
amounts
(ppm)
Cu
complexes
in
presence
various
chemical
reducing
agents
but
also
external
stimuli
such
as
light,
electrical
current
or
mechanical
forces.
can
be
carried
out
bulk,
solution,
and
dispersed
media.
ATRP
has
been
successfully
to
prepare
polymers
with
architecture
well-defined
topology,
composition,
functionality,
well
bioconjugates
organic–inorganic
hybrids.
This
article
summarizes
status
an
outlook
for
ATRP.
Journal of the American Chemical Society,
Journal Year:
2024,
Volume and Issue:
146(9), P. 5786 - 5792
Published: Feb. 21, 2024
To
mitigate
pollution
by
plastic
waste,
it
is
paramount
to
develop
polymers
with
efficient
recyclability
while
retaining
desirable
physical
properties.
A
recyclable
poly(methyl
methacrylate)
(PMMA)
synthesized
incorporating
a
minimal
amount
of
an
α-methylstyrene
(AMS)
analogue
into
the
polymer
structure.
This
P(MMA-
Journal of the American Chemical Society,
Journal Year:
2024,
Volume and Issue:
146(13), P. 9142 - 9154
Published: March 25, 2024
The
development
of
cleavable
comonomers
(CCs)
with
suitable
copolymerization
reactivity
paves
the
way
for
introduction
backbone
deconstructability
into
polymers.
Recent
advancements
in
thionolactone-based
CCs,
exemplified
by
dibenzo[c,e]-oxepine-5(7H)-thione
(DOT),
have
opened
promising
avenues
selective
deconstruction
multiple
classes
vinyl
polymers,
including
polyacrylates,
polyacrylamides,
and
polystyrenics.
To
date,
however,
no
thionolactone
CC
has
been
shown
to
copolymerize
methacrylates
an
appreciable
extent
enable
polymer
deconstruction.
Here,
we
overcome
this
challenge
through
design
a
new
class
benzyl-functionalized
thionolactones
(bDOTs).
Guided
detailed
mechanistic
analyses,
find
that
radical-stabilizing
substituents
bDOTs
enables
markedly
increased
tunable
methyl
methacrylate
(MMA).
Through
iterative
optimizations
molecular
structure,
specific
bDOT,
F-p-CF3PhDOT,
is
discovered
efficiently
MMA.
High
molar
mass
deconstructable
PMMA-based
copolymers
(dPMMA,
Mn
>
120
kDa)
low
percentages
F-p-CF3PhDOT
(1.8
3.8
mol%)
are
prepared
using
industrially
relevant
bulk
free
radical
conditions.
thermomechanical
properties
dPMMA
similar
PMMA;
former
degrade
fragments
(<6.5
under
mild
aminolysis
This
work
presents
first
example
ring-opening
capable
nearly
random
MMA
without
possibility
cross-linking
provides
workflow
mechanism-guided
future.
Science,
Journal Year:
2025,
Volume and Issue:
387(6736), P. 874 - 880
Published: Feb. 20, 2025
The
reversion
of
vinyl
polymers
with
carbon-carbon
backbones
to
their
monomers
represents
an
ideal
path
alleviate
the
growing
plastic
waste
stream.
However,
depolymerizing
such
stable
materials
remains
a
challenge,
state-of-the-art
methods
relying
on
"designer"
that
are
neither
commercially
produced
nor
suitable
for
real-world
applications.
In
this
work,
we
report
main
chain-initiated,
visible
light-triggered
depolymerization
directly
applicable
commercial
containing
undisclosed
impurities
(e.g.,
comonomers,
additives,
or
dyes).
By
in
situ
generation
chlorine
radicals
from
solvent,
near-quantitative
(>98%)
polymethacrylates
could
be
achieved
regardless
synthetic
route
radical
ionic
polymerization),
end
group,
and
molecular
weight
(up
1.6
million
daltons).
possibility
perform
multigram-scale
depolymerizations
confer
temporal
control
renders
methodology
versatile
general
recycling.
