Angewandte Chemie,
Год журнала:
2024,
Номер
unknown
Опубликована: Ноя. 29, 2024
Abstract
Photomediated
Atom
Transfer
Radical
Polymerization
(photoATRP)
is
an
activator
regeneration
method,
which
allows
for
the
controlled
synthesis
of
well‐defined
polymers
via
light
irradiation.
Traditional
photoATRP
often
limited
by
need
high‐energy
ultraviolet
or
violet
light.
These
could
negatively
affect
control
and
selectivity
polymerization,
promote
side
reactions,
may
not
be
applicable
to
biologically
relevant
systems.
This
drawback
can
circumvented
introduction
catalytic
amount
photocatalysts,
absorb
visible
and/or
NIR
and,
therefore,
controlled,
regenerative
ATRP
performed
with
dual‐catalytic
cycle.
Herein,
a
critical
summary
recent
developments
in
field
dual‐catalysis
concerning
Cu‐catalyzed
provided.
Contributions
involved
species
are
examined
mechanistically,
followed
challenges
future
directions
towards
next
generation
advanced
functional
macromolecular
materials.
European Polymer Journal,
Год журнала:
2024,
Номер
211, С. 113001 - 113001
Опубликована: Март 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.
Abstract
Unlike
classical
radical
polymerization,
the
kinetics
of
atom
transfer
polymerization
show
significant
solvent
dependence,
possibly
arising
from
effects
on
activation
step.
A
kinetic
study
initiator
ethyl
α‐bromoisobutyrate
by
[Cu
I
TPMA]
+
(TPMA=tris(2‐pyridylmethyl)amine),
an
initiator/catalyst
combination
frequently
used
in
ATRP,
was
carried
out
DMSO,
DMF,
MeCN,
anisole,
acetate,
and
their
50
vol
%
mixtures
with
styrene
(STY)
methyl
methacrylate
(MMA).
k
act
values
varying
about
3
orders
magnitude
3.14×10
5
mol
−1
dm
s
DMSO
to
9.41×10
2
acetate
were
found.
These
showed
excellent
correlation
polarity/polarizability
parameter
π*.
The
effect
MMA
or
STY
depended
polarity
compatibility
between
monomer
solvent:
After
addition,
decreased
considerably
polar
solvents,
whereas
it
almost
unaffected
nonpolar
solvents.
Journal of the American Chemical Society,
Год журнала:
2024,
Номер
146(32), С. 22247 - 22256
Опубликована: Июль 30, 2024
Solid-phase
polymer
synthesis,
historically
rooted
in
peptide
has
evolved
into
a
powerful
method
for
achieving
sequence-controlled
macromolecules.
This
study
explores
solid-phase
synthesis
by
covalently
immobilizing
growing
chains
onto
poly(ethylene
glycol)
(PEG)-based
resin,
known
as
ChemMatrix
(CM)
resin.
In
contrast
to
traditional
hydrophobic
supports,
CM
resin's
amphiphilic
properties
enable
swelling
both
polar
and
nonpolar
solvents,
simplifying
filtration,
washing,
drying
processes.
Combining
atom
transfer
radical
polymerization
(ATRP)
with
techniques
allowed
the
grafting
of
well-defined
block
copolymers
high
yields.
approach
is
attractive
successfully
synthesizing
di-,
tri-,
tetra-,
penta-block
excellent
control
over
molecular
weight
dispersity.
The
also
delves
limitations
weights
due
confinement
within
resin
pores.
Moreover,
versatility
demonstrated
through
its
applicability
various
monomers
organic
aqueous
media.
straightforward
offers
rapid
route
developing
tailored
unique
structures
functionalities.
European Polymer Journal,
Год журнала:
2024,
Номер
220, С. 113429 - 113429
Опубликована: Сен. 2, 2024
Despite
significant
advancements
in
thermal
and
photothermal
depolymerizations,
the
success
of
these
techniques
relies
on
tedious
deoxygenation
procedures.
Herein,
we
report
development
depolymerization
technique
efficient
without
prior
deoxygenation,
which
was
enabled
by
copper/ligand
complexes
inclusion
(0.25
wt%
relative
to
solvent)
zinc
oxide
(ZnO)
nanocrystals
activated
UV
light.
This
approach
tested
for
poly(methyl
methacrylate)
(PMMA)
prepared
atom
transfer
radical
polymerization
(ATRP);
effects
solvent
polarity
activity
ligands
were
investigated.
Unexpectedly,
a
low-activity
Cu-complex
with
2,2'-bipyridyne
ligand,
combination
low-polarity
solvent,
1,2,4-trichlorobenzene,
relatively
high
yields
less
than
1
h
at
150
°C.
Higher
ATRP
tris(2-pyridylmethyl)amine
(TPMA)
N,N,N',N'',N''-pentamethyldiethylenetriamine
(PMDETA)
ligands,
efficient,
associated
their
decomposition
and/or
excessive
formation
radicals
premature
termination
chain
ends.
The
presented
facile
designed
be
used
even
partially
aerated
reactors,
opening
new
avenues
depolymerization.
Angewandte Chemie International Edition,
Год журнала:
2024,
Номер
unknown
Опубликована: Ноя. 29, 2024
Abstract
Photomediated
Atom
Transfer
Radical
Polymerization
(photoATRP)
is
an
activator
regeneration
method,
which
allows
for
the
controlled
synthesis
of
well‐defined
polymers
via
light
irradiation.
Traditional
photoATRP
often
limited
by
need
high‐energy
ultraviolet
or
violet
light.
These
could
negatively
affect
control
and
selectivity
polymerization,
promote
side
reactions,
may
not
be
applicable
to
biologically
relevant
systems.
This
drawback
can
circumvented
introduction
catalytic
amount
photocatalysts,
absorb
visible
and/or
NIR
and,
therefore,
controlled,
regenerative
ATRP
performed
with
dual‐catalytic
cycle.
Herein,
a
critical
summary
recent
developments
in
field
dual‐catalysis
concerning
Cu‐catalyzed
provided.
Contributions
involved
species
are
examined
mechanistically,
followed
challenges
future
directions
towards
next
generation
advanced
functional
macromolecular
materials.
