Journal of the American Chemical Society,
Год журнала:
2024,
Номер
147(1), С. 889 - 897
Опубликована: Дек. 24, 2024
Biomacromolecular
networks
with
multiscale
fibrillar
structures
are
characterized
by
exceptional
mechanical
properties,
making
them
attractive
architectures
for
synthetic
materials.
However,
there
is
a
dearth
of
polymeric
building
blocks
capable
forming
similarly
structured
networks.
Bottlebrush
polymers
(BBPs)
anisotropic
graft
the
potential
to
mimic
and
replace
biomacromolecules
such
as
tropocollagen
fabrication
networks;
however,
longstanding
limitation
BBPs
has
been
lack
rigidity
necessary
access
lyotropic
ordering
that
underpins
formation
collagenous
While
correlation
between
BBP
grafting
density
well
established,
approaches
rigidify
increased
underdeveloped.
To
address
this
gap
in
capability,
we
report
synthesis
novel
macroinitiators
provide
well-defined
an
unprecedentedly
high
density.
A
suite
light
scattering
techniques
used
correlate
macromolecular
architecture
demonstrate
first
time
poly(norbornene)
exhibit
long-range
result
their
rodlike
character.
Specifically,
newly
reported
ultradensely
grafted
structures,
preparable
on
multigram
scale,
form
hexagonal
arrays
while
conventional
do
not,
despite
showing
spatial
correlations.
These
results
implicate
central
role
entanglement
solution
phase
assembly
new
fundamental
insight
broadly
relevant
performance
BBP-derived
materials,
spanning
biomedical
research
photonic
materials
thermal
management
technologies.
Furthermore,
these
liquid
crystalline
structural
template
explore
untapped
bottom-up
semiflexible
ultimately
intended
modular
route
hierarchically
biomimetic
Chemical Communications,
Год журнала:
2025,
Номер
unknown
Опубликована: Янв. 1, 2025
This
article
highlights
the
advancements
in
controlled
radical
polymerization
facilitated
by
three
external
regulations
of
oxygen,
light,
and
mechanical
force,
outlines
future
directions
polymerization.
Journal of the American Chemical Society,
Год журнала:
2025,
Номер
unknown
Опубликована: Янв. 16, 2025
In
traditional
atom
transfer
radical
polymerization
(ATRP),
oxygen
must
be
meticulously
eliminated
due
to
its
propensity
quench
species
and
halt
the
process.
Additionally,
oxidizes
lower-valent
Cu
catalyst,
compromising
ability
activate
alkyl
halides
propagate
polymerization.
this
study,
we
present
an
oxygen-driven
ATRP
utilizing
alkylborane
compounds,
a
method
that
not
only
circumvents
need
for
stringent
removal
but
also
exploits
as
essential
cofactor
promote
This
approach
exhibits
broad
compatibility
in
organic
or
aqueous
media,
yielding
well-defined
polymers
with
low
dispersity
(Đ
1.11)
molecular
weights
closely
aligned
theoretical
values.
Triethylborane
(Et3B)
air-stable
triethylborane-amine
complex
(Et3B-DMAP)
facilitate
controlled
under
open-to-air
conditions,
demonstrating
efficiency
across
wide
range
of
monomers.
Moreover,
technique
enables
successful
synthesis
protein–polymer
conjugates
supports
surface
modifications
nanoparticles
silicon
wafers
aerobic
conditions.
represents
robust
versatile
platform
precision
far-reaching
implications
materials
science,
biomedicine,
advanced
engineering.
Nature Communications,
Год журнала:
2024,
Номер
15(1)
Опубликована: Июнь 17, 2024
Abstract
Atom
transfer
radical
polymerization
(ATRP)
with
dual
photoredox/copper
catalysis
combines
the
advantages
of
photo-ATRP
and
photoredox-mediated
ATRP,
utilizing
visible
light
ensuring
broad
monomer
scope
solvent
compatibility
while
minimizing
side
reactions.
Despite
its
popularity,
challenges
include
high
photocatalyst
(PC)
loadings
(10
to
1000
ppm),
requiring
additional
purification
increasing
costs.
In
this
study,
we
discover
a
PC
that
functions
at
sub-ppm
level
for
ATRP
through
mechanism-driven
design.
Through
studying
mechanisms,
find
efficient
polymerizations
are
driven
by
PCs
whose
ground
state
oxidation
potential—responsible
regeneration—play
more
important
role
than
their
excited
reducing
power,
responsible
initiation.
This
is
verified
screening
varying
redox
potentials
triplet
generation
capabilities.
Based
on
these
findings,
identify
highly
PC,
4DCDP-IPN,
featuring
moderate
power
maximized
potential.
Employing
50
ppb,
synthesize
poly(methyl
methacrylate)
conversion,
narrow
molecular
weight
distribution,
chain-end
fidelity.
system
exhibits
oxygen
tolerance
supports
large-scale
reactions
under
ambient
conditions.
Our
systematic
design,
offer
meaningful
insights
controlled
metallaphotoredox-mediated
syntheses
beyond
ATRP.
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.
Chinese Journal of Chemistry,
Год журнала:
2025,
Номер
unknown
Опубликована: Март 20, 2025
Comprehensive
Summary
Substantial
progress
has
been
made
over
recent
years
in
visible
light‐driven
dual
photoredox/copper
catalyzed
atom
transfer
radical
polymerization
(photo‐ATRP)
through
the
design
of
photocatalysts
(PCs)
and
optimization
reaction
conditions.
However,
it
remains
challenging
to
achieve
efficient
photo‐ATRP
with
low
loadings
both
photocatalyst
copper(II).
In
this
study,
two
donor‐acceptor
organic
PCs
based
on
pyrazino[2,3‐
f
][1,10]phenanthroline
were
successfully
used
Cu(II)‐mediated
photo‐ATRP.
These
exhibit
excellent
light
absorption
capabilities
thermally
activated
delayed
fluorescence
(TADF)
properties.
Under
blue
irradiation,
facilitated
highly
oxygen‐tolerant
an
extremely
catalyst
loading
(50
ppb).
This
system
demonstrated
a
broad
applicability
various
monomers,
achieving
successful
methacrylates,
acrylates,
styrene.
Additionally,
large
scale
(250
mL)
was
achieved,
resulting
narrow
molecular
weight
polymers
high
monomer
conversions
chain‐end
fidelity.
work
provides
in‐depth
investigation
into
regulatory
process
photo‐ATRP,
offering
new
insights
intricate
mechanism
oxygen
tolerance.
