Polymer Chemistry,
Год журнала:
2018,
Номер
9(33), С. 4332 - 4342
Опубликована: Янв. 1, 2018
Phenylhydrazine
is
an
effective
modifier
for
conventional
ATRP
syntheses,
providing
systematic
control
over
the
dispersity
of
polymers
with
unimodal
molecular
weight
distributions.
Chemical Science,
Год журнала:
2019,
Номер
10(38), С. 8724 - 8734
Опубликована: Янв. 1, 2019
The
width
and
shape
of
molecular
weight
distributions
can
significantly
affect
the
properties
polymeric
materials
thus
are
key
parameters
to
control.
This
mini-review
aims
critically
summarise
recent
approaches
developed
tailor
highlights
strengths
limitations
each
technique.
Special
emphasis
will
also
be
given
applications
where
tuning
distribution
has
been
used
as
a
strategy
not
only
enhance
polymer
but
increase
fundamental
understanding
behind
complex
mechanisms
phenomena.
Angewandte Chemie International Edition,
Год журнала:
2019,
Номер
58(38), С. 13323 - 13328
Опубликована: Июль 10, 2019
Dispersity
significantly
affects
the
properties
of
polymers.
However,
current
methods
for
controlling
polymer
dispersity
are
limited
to
bimodal
molecular
weight
distributions,
adulterated
chains,
or
low
end-group
fidelity
and
rely
on
feeding
reagents,
flow-based,
multicomponent
systems.
To
overcome
these
limitations,
we
report
a
simple
batch
system
whereby
photoinduced
atom
transfer
radical
polymerisation
is
exploited
as
convenient
versatile
technique
control
both
homopolymers
block
copolymers.
By
varying
concentration
copper
complex,
wide
range
monomodal
distributions
can
be
obtained
(Đ=1.05-1.75).
In
all
cases,
high
was
confirmed
by
MALDI-ToF-MS
exemplified
efficient
copolymer
formation
(monomodal,
Đ=1.1-1.5).
Importantly,
our
approach
utilises
ppm
levels
(as
4
ppm),
tolerant
oxygen
exhibits
perfect
temporal
control,
representing
major
step
forward
in
tuning
various
applications.
Macromolecules,
Год журнала:
2018,
Номер
51(12), С. 4553 - 4563
Опубликована: Июнь 7, 2018
We
report
a
novel
semicontinuous
method
for
producing
polymer
mixtures
with
tailored
molecular
weight
distributions
(MWDs)
and
chemical
compositions.
In
contrast
to
recent
methods
disclosed
the
production
of
MWDs,
current
approach
allows
MWD
be
at
any
point
in
multistep
process.
Optimization
photoflow
polymerization
process
has
been
performed,
where
fractions
variable
compositions
can
produced
independently
processed
downstream.
This
independent
processing
complex
tedious
operations
significantly
simplified
structure
manipulated
by
varying
conditions.
To
illustrate
versatility
our
approach,
we
prepared
low
dispersity
block
copolymer
composition
gradients
through
PET-RAFT
polymerization,
using
facile
one-pass
flow
technique.
Nature Communications,
Год журнала:
2020,
Номер
11(1)
Опубликована: Июнь 18, 2020
Abstract
The
properties
of
a
polymer
are
known
to
be
intrinsically
related
its
molecular
weight
distribution
(MWD);
however,
previous
methodologies
MWD
control
do
not
use
design
and
result
in
arbitrary
shaped
MWDs.
Here
we
report
precise
synthesis
protocol
for
producing
targeted
with
simple
use,
chemistry
agnostic
computer-controlled
tubular
flow
reactor.
To
support
the
development
this
protocol,
constructed
general
reactor
rules
by
combining
fluid
mechanical
principles,
polymerization
kinetics,
experiments.
ring
opening
lactide,
anionic
styrene,
metathesis
used
as
model
polymerizations
develop
synthesize
profiles.
derivation
mathematical
enables
quantitative
prediction
experimental
results,
provides
tool
explore
limits
any
protocol.
Journal of the American Chemical Society,
Год журнала:
2019,
Номер
142(3), С. 1443 - 1448
Опубликована: Дек. 27, 2019
High-density
polyethylene
(HDPE)
is
utilized
in
a
multitude
of
commercial
products
worldwide
due
to
its
broad
spectrum
physical
properties
and
low
production
costs.
Molecular
weight
dispersity
(Đ)
are
known
affect
the
tensile
rheological
HDPE,
but
little
about
influence
molecular
distribution
(MWD)
shape
on
these
properties.
In
this
work,
we
investigate
matter
through
temporal
regulation
initiation
living
coordination–insertion
polymerization
ethylene.
This
method
provides
precise
control
over
MWD
which,
turn,
offers
systematic
study
HDPE.
Through
testing,
observe
difference
complex
viscosity
shear
thinning
with
opposite
skew.
However,
testing
reveals
that
skew
does
not
impact
strain
at
break,
signifying
ability
HDPE
processing
without
compromising
material
strength.