Journal of the American Chemical Society,
Год журнала:
2024,
Номер
146(19), С. 13417 - 13426
Опубликована: Май 1, 2024
Photoinduced
polymerization
techniques
have
gathered
significant
attention
due
to
their
mild
conditions,
spatiotemporal
control,
and
simple
setup.
In
addition
homogeneous
media,
efforts
been
made
implement
photopolymerization
in
emulsions
as
a
practical
greener
process.
However,
previous
photoinduced
reversible
deactivation
radical
(RDRP)
heterogeneous
media
has
relied
on
short-wavelength
lights,
which
limited
penetration
depth,
resulting
slow
relatively
poor
control.
this
study,
we
demonstrate
the
first
example
of
highly
efficient
miniemulsion
ATRP
open
air
driven
by
red
or
near-infrared
(NIR)
light.
This
was
facilitated
utilization
water-soluble
photocatalyst,
methylene
blue
(MB+).
Irradiation
red/NIR
light
allowed
for
excitation
MB+
subsequent
photoreduction
deactivator
presence
electron
donors
initiate
mediate
The
NIR
light-driven
photoATRP
provided
successful
synthesis
polymers
with
low
dispersity
(1.09
≤
Đ
1.29)
quantitative
conversion
within
an
hour.
study
further
explored
impact
kinetics
reactors
varying
sizes
large-scale
reaction
(250
mL),
highlighting
advantages
longer-wavelength
light,
particularly
dispersed
owing
its
superior
penetration.
work
opens
new
avenues
robust
emulsion
techniques,
offering
more
approach
improved
control
efficiency.
Abstract
The
development
of
advanced
materials
based
on
well‐defined
polymeric
architectures
is
proving
to
be
a
highly
prosperous
research
direction
across
both
industry
and
academia.
Controlled
radical
polymerization
techniques
are
receiving
unprecedented
attention,
with
reversible‐deactivation
chain
growth
procedures
now
routinely
leveraged
prepare
exquisitely
precise
polymer
products.
Reversible
addition‐fragmentation
transfer
(RAFT)
powerful
protocol
within
this
domain,
where
the
unique
chemistry
thiocarbonylthio
(TCT)
compounds
can
harnessed
control
vinyl
polymers.
With
intense
recent
focus
RAFT,
new
strategies
for
initiation
external
have
emerged
that
paving
way
preparing
polymers
demanding
applications.
In
work,
cutting‐edge
innovations
in
RAFT
opening
up
technique
broader
suite
researchers
explored.
Emerging
activating
TCTs
surveyed,
which
providing
access
into
traditionally
challenging
environments
polymerization.
latest
advances
future
perspectives
applying
RAFT‐derived
also
shared,
goal
convey
rich
potential
an
ever‐expanding
range
high‐performance
Angewandte Chemie International Edition,
Год журнала:
2020,
Номер
60(10), С. 5489 - 5496
Опубликована: Ноя. 12, 2020
Abstract
In
this
study,
porphyrinic
zirconium
(Zr)
MOFs
were
investigated
as
heterogeneous
photocatalysts
for
photoinduced
electron
transfer‐reversible
addition‐fragmentation
chain
transfer
(PET‐RAFT)
polymerization
of
various
monomers
under
a
broad
range
wavelengths,
producing
polymers
with
high
monomer
conversions,
narrow
molecular
weight
distributions,
low
dispersity
and
good
chain‐end
fidelity.
Screening
Zr‐MOFs
(Zn)
containing
Zn‐metalled
ligands
demonstrated
that
MOF‐525
the
smallest
size
had
best
photocatalytic
activity
in
PET‐RAFT
polymerization,
due
to
enhanced
dispersion
light
penetration.
Oxygen
tolerance
temporal
control
also
during
MOF
catalysed
PET‐RAFT.
Results
suggested
rates
significantly
affected
by
changing
surface
area
MOFs,
could
be
easily
separated
recycled
up
five
independent
polymerizations
without
an
obvious
decrease
efficiency.
Finally,
utilized
create
three‐dimensional
polymeric
objects
resolution
via
visible
mediated
stereolithography
open‐air
environment.
Chemical Society Reviews,
Год журнала:
2023,
Номер
52(9), С. 3035 - 3097
Опубликована: Янв. 1, 2023
In
this
review,
we
provide
a
brief
history,
progress,
and
applications,
discuss
the
remaining
challenges
of
photocontrolled
reversible
addition-fragmentation
chain
transfer
(RAFT)
polymerization
(i.e.,
photoinduced
electron/energy
transfer-RAFT
(PET-RAFT),
photoiniferter,
photomediated
cationic
RAFT
polymerization).
Among
these,
visible-light-driven
has
attracted
particular
attention
in
recent
years
due
to
its
benefits,
including
low
energy
consumption
safe
reaction
procedure.
Moreover,
incorporation
visible-light
photocatalysis
conferred
attractive
features,
such
as
spatiotemporal
control
oxygen
tolerance;
however,
clear
understanding
mechanism
not
been
completely
provided.
We
also
present
research
efforts
elucidate
mechanisms
with
aid
quantum
chemical
calculations
combined
experimental
evidence.
This
review
offers
an
insight
into
better
design
systems
for
desired
applications
helps
realize
full
potential
both
academic-
industrial-scale
applications.
Angewandte Chemie International Edition,
Год журнала:
2021,
Номер
60(16), С. 8839 - 8850
Опубликована: Янв. 15, 2021
Abstract
RAFT
facilitated
digital
light
projection
3D
printing
of
polymeric
materials
provides
a
convenient
and
facile
route
for
inducing
post‐fabrication
transformations
via
reactivation
dormant
chain
transfer
agents.
In
this
work,
we
report
the
use
Norrish
type
I
photoinitiator
in
conjunction
with
agent
to
produce
variety
open‐air
printable
resins
that
rapidly
cure
under
visible
irradiation.
The
photoinitiator‐RAFT
system
polymerizes
extremely
quickly
high
build
rates
up
9.1
cm
h
−1
,
representing
7‐fold
increase
compared
previous
mediated
systems.
printed
containing
thiocarbonylthio
groups
can
be
also
produced
using
low
concentrations
divinyl
comonomers
initial
resins,
which
has
not
been
successfully
achieved
other
photocontrolled
polymerization
techniques.
Interestingly,
inclusion
agents
significantly
improves
resolution
formulations
without
agent,
allowing
fabrication
intricate
complex
objects.
Spatiotemporally
controlled
surface
modifications
objects
from
on
material
surfaces
were
performed
one
two‐pass
configurations,
multiple
successive
post‐printing
same
object.
Macromolecular Rapid Communications,
Год журнала:
2021,
Номер
43(1)
Опубликована: Ноя. 9, 2021
Light-mediated
polymerization
techniques
offer
distinct
advantages
over
reactions
fueled
by
thermal
energy,
such
as
high
spatial
and
temporal
control
well
the
possibility
to
work
under
mild
reaction
conditions.
Reversible
addition-fragmentation
chain-transfer
(RAFT)
is
a
highly
versatile
radical
method
that
can
be
utilized
variety
of
monomers
produce
vast
number
complex
macromolecular
structures.
The
use
light
drive
RAFT-polymerization
possible
via
multiple
routes.
Besides
photo-initiators,
or
photo-catalysts,
direct
activation
chain
transfer
agent
controlling
RAFT
process
in
photo-iniferter
(PI)
an
elegant
way
initiate
reactions.
Within
this
review,
PI-RAFT
its
conventional
are
discussed
detail.
Polymers,
Год журнала:
2025,
Номер
17(4), С. 515 - 515
Опубликована: Фев. 17, 2025
Porous
polymer
membranes
with
highly
interconnected
open-cellular
structure
and
high
toughness
are
crucial
for
various
application
fields.
Polymerized
internal
phase
emulsions
(polyHIPEs),
which
usually
exist
as
monoliths,
possess
the
advantages
of
porosity
good
connectivity.
However,
it
is
difficult
to
prepare
due
brittleness
easy
pulverization.
Copolymerizing
acrylate
soft
monomers
can
effectively
improve
polyHIPEs,
but
cause
emulsion
instability
pore
collapse.
In
this
paper,
stable
HIPEs
a
content
butyl
(41.7
mol%
75
based
on
monomers)
be
obtained
by
using
composite
emulsifier
(30
wt.%
consisting
Span80/DDBSS
(9/2
in
molar
ratio)
adding
0.12
mol·L-1
CaCl2
according
aqueous
concentration.
On
basis,
polyHIPE
extent
firstly
prepared
via
reversible
addition-fragmentation
chain
transfer
(RAFT)
polymerization.
The
addition
RAFT
agent
significantly
improves
mechanical
properties
without
affecting
structure.
polymerization
enhanced
compared
conventional
free
radical
When
ratio
acrylate/styrene/divinylbenzene
7/4/1,
membrane
presents
plastic
deformation
during
tensile
test.
modulus
reaches
93.04
±
12.28
kJ·m-3
while
92.35%,
also
has
excellent
thermal
stability.
Journal of the American Chemical Society,
Год журнала:
2021,
Номер
143(17), С. 6357 - 6362
Опубликована: Апрель 26, 2021
By
virtue
of
spatiotemporal
control
over
the
chain
propagating,
visible-light-regulated
organocatalytic
photoredox
cationic
polymerization
provides
an
appealing
approach
for
construction
metal-free,
well-defined
polymers
and
materials.
However,
so
far,
organic
photocatalysts
capable
mediated
vinyl
ethers
are
quite
limited,
photocontrol
or
efficiency
is
often
eroded
due
to
difficulty
in
achieving
a
good
activation–deactivation
balance,
which
greatly
dependent
on
redox
property
catalyst.
Here,
we
introduce
new
type
photocatalysts,
bisphosphonium
salts,
show
high
performance
photoregulated
reversible
addition–fragmentation
transfer
allow
synthesis
poly(vinyl
ethers)
with
predictable
molecular
weights
narrow
dispersities
at
low
ppm
catalyst
loadings
under
visible
light.
In
particular,
tunable
potential
excellent
stability
endow
salts
strict
temporal
control,
thus
enabling
metal-free
halt
long
dark
period.