Macromolecules,
Год журнала:
2024,
Номер
57(4), С. 1546 - 1555
Опубликована: Фев. 11, 2024
A
series
of
biobased
alipharomatic
polyesters
using
vanillin-derived
bifunctional
hydroxy-aldehyde
monomers
(M1)s
as
the
starting
materials
are
synthesized
through
direct
dehydrogenative
polycondensation
with
commercially
available
Milstein
catalyst.
The
thermal
properties
resulting
P(M1)s
can
be
precisely
tuned
by
altering
alkylene
length
monomers,
a
maximum
Tg
value
reaching
37.9
°C.
Compared
to
reported
vanillic
acid-based
polyesters,
synthesis
M1
is
less
labor-intensive,
and
polymerization
conditions
milder
than
those
conventional
polycondensation.
Additionally,
experimental
results
mechanism
elucidations
revealed
four
different
types
ester
linkages
in
P(M1)
chain.
ruthenium
dihydride
complex
has
been
identified
true
active
species
required
for
promoting
into
polyesters.
Moreover,
this
catalytic
system
also
exhibits
depolymerization
capability
toward
polyester
back
diol
(M2),
which
then
repolymerized
P(M2)
an
identical
structure
that
P(M1),
thus
demonstrating
rare
example
where
two
yield
same
polymer
product.
This
study
presents
green
economical
approach
preparation
recycling
widely
used
ACS Materials Letters,
Год журнала:
2024,
Номер
6(8), С. 3899 - 3908
Опубликована: Июль 25, 2024
Traditional
commercial
thermosetting
materials
are
currently
facing
significant
challenges
in
terms
of
reprocessing,
degradation,
and
recycling
because
a
large
demand
petroleum
resources,
leading
to
environmental
burden.
In
our
work,
trialdehyde
monomer
synthesized
by
renewable
resource
reacted
with
1,4-Bis(4-amino-2-trifluoromethylphenoxy)benzene
1,4-Bis(4-aminophenoxy)benzene
form
dynamic
cross-linked
network
called
BQPs.
The
fluorinated
biobased
polyimine
material
exhibits
exceptional
mechanical
properties
tensile
strength
96.2
MPa,
which
is
much
higher
than
plastics
such
as
polycarbonate
(∼65
MPa).
Moreover,
it
demonstrates
excellent
flame
retardancy
achieving
level
V0
rating
the
UL-94
test
value
50%
limiting
oxygen
index
test.
Additionally,
can
be
easily
reprocessed
within
10
min
at
high
temperature
(160
°C)
rapidly
repaired
solvent.
Overall,
this
high-performance
product
will
significantly
contribute
expanding
development
materials.
Nature Communications,
Год журнала:
2025,
Номер
16(1)
Опубликована: Фев. 25, 2025
The
precise
placement
of
thioester
bonds
into
sequence-controlled
polymers
remains
a
grand
challenge.
Here,
we
demonstrate
the
versatile
synthesis
from
step
polymerization
cyclic
thioanhydrides
(A),
diacrylates
(B),
and
diols/diamines
(C).
In
addition
to
easily
accessible
diverse
monomers,
method
is
metal-free/catalyst-free,
atom-economical,
wide
in
monomer
scope,
yielding
107
with
>90%
yields
weight-average
molecular
weights
up
175.4
kDa.
obtained
contain
ABAC-type
repeating
units
precisely
distributed
in-chain
ester
(and
amide)
groups.
chemoselectivity
revealed
by
density
functional
theory
calculations.
polymer
library
exhibits
considerably
tunable
performance:
glass-transition
temperatures
−36–72
°C,
melting
43–133
degradability,
thermoplastics/elastomers,
thioester-based
functions.
This
study
furnishes
facile
incorporate
polymers.
challenging.
authors
thioanhydrides,
diacrylates,
diols/diamines.
Angewandte Chemie International Edition,
Год журнала:
2024,
Номер
63(24)
Опубликована: Апрель 8, 2024
Abstract
Polyesters,
a
highly
promising
class
of
circular
polymers
for
achieving
closed‐loop
sustainable
plastic
economy,
inherently
exhibit
material
stability
defects,
especially
in
thermal
and
hydrolytic
instability.
Here,
we
introduce
polyesters,
P(4
R
‐BL)
(R=Ph,
Bu),
featuring
conformationally
rigid
1,3
‐
cyclobutane
rings
the
backbone.
These
polyesters
not
only
superior
thermostability
(
T
d,5%
=376–380
°C)
but
also
demonstrate
exceptional
resistance
with
good
integrity
even
after
1
year
basic
acidic
aqueous
solutions,
distinguishing
themselves
from
typical
counterparts.
Tailoring
flexibility
side
group
enables
controlled
mechanical
performance
Ph
Bu
to
rival
durable
syndiotactic
polystyrene
(SPS)
low‐density
polyethylene
(LDPE),
respectively.
Significantly,
despite
their
high
stability,
both
can
be
effectively
depolymerized
into
pristine
monomers,
establishing
life
cycle.
Angewandte Chemie International Edition,
Год журнала:
2024,
Номер
63(9)
Опубликована: Янв. 5, 2024
Abstract
Polythioesters
are
important
sustainable
polymers
with
broad
applications.
The
ring‐opening
polymerization
(ROP)
of
S
‐Carboxyanhydrides
(SCAs)
can
afford
polythioesters
functional
groups
that
typically
difficult
to
prepare
by
ROP
thiolactones.
Typical
methods
involving
organocatalysts,
like
dimethylaminopyridine
(DMAP)
and
triethylamine
(Et
3
N),
have
been
plagued
uncontrolled
polymerization,
including
epimerization
for
most
SCAs
resulting
in
the
loss
isotacticity.
Here,
we
report
use
salen
aluminum
catalysts
selective
various
without
epimerization,
affording
functionalized
polythioester
high
molecular
weight
up
37.6
kDa
highest
P
m
value
0.99.
Notably,
TlaSCA
(SCA
prepared
from
thiolactic
acid)
generates
first
example
a
isotactic
crystalline
poly(thiolactic
acid),
which
exhibited
distinct
T
152.6
°C.
Effective
ligand
tailoring
governs
binding
affinity
between
sulfide
chain‐end
metal
center,
thereby
maintaining
activity
organometallic
reducing
occurrence
reactions.
Angewandte Chemie International Edition,
Год журнала:
2024,
Номер
63(29)
Опубликована: Апрель 29, 2024
Abstract
Isotactic
polythioesters
(PTEs)
that
are
thioester
analogs
to
natural
polyhydroxyalkanoates
(PHAs)
have
attracted
growing
attention
due
their
distinct
properties.
However,
the
development
of
chemically
synthetic
methods
for
preparing
isotactic
PTEs
has
long
been
an
intricate
endeavour.
Herein,
we
report
successful
synthesis
perfectly
via
stereocontrolled
ring‐opening
polymerization.
This
binaphthalene‐salen
aluminium
(SalBinam‐Al)
catalyst
promoted
a
robust
polymerization
rac
‐α‐substituted‐β‐propiothiolactones
(
‐BTL
and
‐PTL)
with
highly
kinetic
resolution,
affording
P(BTL)
P(PTL)
M
n
up
276
kDa.
Impressively,
formed
supramolecular
stereocomplex
improved
thermal
property
T
m
=204
°C).
Ultimately,
this
resolution
enabled
facile
isolation
enantiopure
S
)‐BTL,
which
could
efficiently
convert
important
pharmaceutical
building
block
)‐2‐benzyl‐3‐mercapto‐propanoic
acid.
served
as
tough
ductile
material
comparable
commercialized
polyolefins.
system
allowed
access
PTEs,
establishing
powerful
platform
discovery
sustainable
plastics.
Fundamental Research,
Год журнала:
2024,
Номер
unknown
Опубликована: Июнь 1, 2024
Whilst
polymers
have
played
a
significant
role
in
the
development
of
modern
society,
rapid
growth
polymer
waste
is
disadvantageously
influencing
communities
and
ecosystems
across
world.
Constructing
closed-loop
life
cycle
materials
urgently
demand.
Chemical
recycling
polyesters,
which
can
be
recovered
to
pristine
monomers
or
transformed
other
value-added
products,
has
been
considered
as
an
appealing
approach
circular
economy
attracted
enormous
attention
last
several
years.
This
review
highlights
some
recent
progress
chemical
diverse
including
commercialized
poly(lactic
acid),
poly(ε-caprolactone),
poly(ethylene
terephthalate),
well
various
novel
chemically
recyclable
polyesters
polycarbonates.
Eventually,
based
on
these
technological
developments,
we
discuss
remaining
challenges
identify
promising
research
opportunities,
providing
insights
into
future
directions
for
achieving
genuine
economy.
