Frontiers in Chemistry,
Journal Year:
2022,
Volume and Issue:
10
Published: Aug. 17, 2022
As
the
core
unit
of
energy
storage
equipment,
high
voltage
pulse
capacitor
plays
an
indispensable
role
in
field
electric
power
system
and
electromagnetic
related
equipment.
The
mostly
utilized
polymer
materials
are
metallized
thin
films,
which
represented
by
biaxially
oriented
polypropylene
(BOPP)
possessing
advantages
including
low
cost,
breakdown
strength,
excellent
processing
ability,
self-healing
performance.
However,
dielectric
constant
(
ε
r
<
3)
traditional
BOPP
films
makes
it
impossible
to
meet
demand
for
increased
density.
Controlled/living
radical
polymerization
(CRP)
techniques
have
become
a
powerful
approach
tailor
chemical
physical
properties
given
rise
great
advances
tuning
dielectrics.
Although
organic-inorganic
composite
dielectrics
received
much
attention
previous
studies,
all-organic
been
proven
be
most
promising
choice
because
its
light
weight
easy
large-scale
continuous
processing.
In
this
short
review,
we
begin
with
some
basic
theory
theoretical
considerations
rational
design
polymers
guidance
these
considerations,
review
recent
progress
toward
based
on
two
major
approaches,
one
is
control
chain
structure,
containing
microscopic
main-chain
side-chain
structures,
method
CRP
other
macroscopic
structure
films.
And
various
chemistry
compositions
discussed
within
each
approach.
RSC Advances,
Journal Year:
2022,
Volume and Issue:
12(40), P. 26023 - 26041
Published: Jan. 1, 2022
Herein,
we
delignated
the
synthesis
of
a
novel
inorganic
sulfurous
magnetic
solid
acid
catalyst
by
immobilization
an
extremely
high
content
sulfuric
functionalities
on
amorphous
silica-modified
hercynite
nanomagnetic
core-shell
via
simple
method.
Silica
(SSA)
modified
nanocomposite
(hercynite@SSA)
combines
excellent
recoverability
and
stability
characteristics
(which
can
be
regarded
as
ferro
spinel
with
Fd3m
space
group
cubic
crystal
structure)
strong
Brønsted
properties
-SO3H
groups.
This
was
found
to
efficient
facile
for
bis(pyrazolyl)methanes
two
different
one-pot
multicomponent
methodologies
under
green
conditions.
The
hercynite@SSA
shows
catalytic
activity
reusability
in
ethanolic
medium
among
materials.
A
plausible
reaction
mechanism
is
proposed
this
synthesis.
ACS Polymers Au,
Journal Year:
2024,
Volume and Issue:
4(3), P. 189 - 207
Published: Feb. 29, 2024
In
recent
times,
the
evolution
of
cationic
polymerization
has
taken
a
multidirectional
approach,
with
development
reversible
addition-fragmentation
chain
transfer
(RAFT)
polymerization.
contrast
to
conventional
methods,
which
were
typically
carried
out
under
inert
atmospheres
and
low
temperatures,
various
novel
techniques
have
been
developed
where
reactions
are
in
open
air,
operate
at
room
temperature,
cost-effective,
environmentally
friendly.
Besides,
several
external
stimuli,
such
as
heat,
light,
chemicals,
electrical
potential,
etc.
employed
activate
control
process.
It
also
enables
combination
other
methods
single
reaction
vessel,
eliminating
necessity
for
isolation
purification
during
intermediate
steps.
addition,
significant
advancements
made
through
modifications
catalyst
systems,
resulting
polymers
an
exceptionally
high
level
stereoregularity.
This
review
article
comprehensively
analyses
developments
polymerization,
encompassing
their
applications
offering
insights
into
future
perspectives.
Journal of the American Chemical Society,
Journal Year:
2024,
Volume and Issue:
146(10), P. 6449 - 6455
Published: Feb. 5, 2024
By
virtue
of
noninvasive
regulations
by
light,
photocontrolled
polymerizations
have
attracted
considerable
attention
for
the
precision
synthesis
macromolecules.
However,
a
cationic
polymerization
with
simultaneous
photocontrol
and
tacticity-regulation
remains
elusive
so
far.
Herein,
we
introduce
an
asymmetric
ion-pairing
photoredox
catalysis
strategy
that
allows
development
stereoselective
concurrent
light
regulation
first
time.
employing
ion
pair
catalyst
(PC+/*A–)
consisting
active
cation
(PC+)
sterically
confined
chiral
anion
(*A–)
to
deliver
stereochemical
control,
vinyl
ethers
can
be
achieved
high
isotactic
selectivity
(up
91%
m)
at
remarkable
low
loading
(50
ppm).
ACS Catalysis,
Journal Year:
2023,
Volume and Issue:
13(5), P. 3272 - 3284
Published: Feb. 20, 2023
Controlling
polymer
tacticity
is
a
key
consideration
in
macromolecular
synthesis
due
to
the
impact
of
stereochemistry
on
material's
thermomechanical
and
optical
properties.
Recently,
inspired
by
work
small
molecule
catalysis,
asymmetric
ion-pairing
has
emerged
as
valuable
approach
control
polymers
made
through
chain
growth
polymerization
vinyl
monomers.
This
Perspective
outlines
some
challenges
inherent
stereocontrol
well
highlights
recent
catalyst
development
area
that
enabled
both
configuration
conformation
polymers.
Several
synthetic
opportunities
mechanistic
questions
have
been
identified
will
expand
synthesis.
Journal of the American Chemical Society,
Journal Year:
2022,
Volume and Issue:
144(19), P. 8487 - 8492
Published: May 5, 2022
Helical
polymers
with
a
defined
main-chain
atropoisomeric
conformation
are
important
materials
in
high
value
applications
such
as
nonlinear
optics
and
chiral
separations.
Currently,
no
methods
exist
for
the
cationic
helix-sense-selective
polymerization
of
prochiral
vinyl
monomers,
which
limits
access
to
number
potentially
valuable
optically
active
helical
polymers.
Here,
we
demonstrate
first
stereoselective
monomer,
provides
helices
poly(N-vinylcarbazole).
Chiral
bis(oxazoline)-scandium
Lewis
acids
serve
counterions
polymerize
N-vinylcarbazole
into
highly
isotactic
(up
94%
meso
triads)
Mechanistic
investigations
uncovered
distinct
phenomenon
that
responsible
independent
control
conformational
(i.e.,
helicity)
configurational
tacticity)
stereochemistry.
Polymer
helicity
was
strongly
influenced
by
stereoselectivity
monomer
propagation,
whereas
polymer
tacticity
dictated
thermodynamically
controlled
growing
chain
end.
Overall,
this
method
expands
suite
accessible
through
mechanistic
insight
how
can
be
independently.
Macromolecules,
Journal Year:
2022,
Volume and Issue:
55(13), P. 5756 - 5765
Published: June 27, 2022
Cationic
polymerization
of
isobutyl
vinyl
ether
(IBVE)
was
investigated
using
Schreiner's
thiourea
(STU)
combined
with
Im-TEPB
bearing
a
2-iodoimidazolium
cation
and
noncoordinating
borate
anion.
Both
the
CF3CO2H
adduct
HCl
IBVE
had
ability
to
initiate
polymerization,
but
number-averaged
molecular
weight
rather
low
compared
theoretical
value
distribution
fairly
broad
(Mw/Mn
>
2.6).
On
other
hand,
fast
cationic
p-methoxystyrene
(pMOS,
50
equiv
relative
pMOS·HCl)
proceeded
STU/Im-TEPB
cocatalysts,
giving
rise
poly(pMOS)
Mn
=
4580
Mw/Mn
1.38.
STU/Im-TfO
exhibited
decreased
activity
due
coordination
trifluoromethanesulfonate
counteranion
NH
group
STU,
which
supported
by
NMR
spectrum,
DFT
calculation,
UV–vis
titration
experiment.
The
could
be
roughly
regulated
cocatalysis
between
2400
7500
monomer
feed
ratio
keeping
below
1.41,
although
these
values
were
lower
than
ones
probably
unignorable
chain-transfer
reaction.
kinetics
revealed
that
consumption
rate
depends
on
concentration
reveals
catalytic
function
STU/Im-TEPB.
