Chemical Reviews,
Journal Year:
2024,
Volume and Issue:
124(18), P. 10435 - 10508
Published: Sept. 16, 2024
The
mechanical
properties
of
polymer
gels
devote
to
emerging
devices
and
machines
in
fields
such
as
biomedical
engineering,
flexible
bioelectronics,
biomimetic
actuators,
energy
harvesters.
Coupling
network
architectures
interactions
has
been
explored
regulate
supportive
characteristics
gels;
however,
systematic
reviews
correlating
mechanics
interaction
forces
at
the
molecular
structural
levels
remain
absent
field.
This
review
highlights
engineering
gel
a
comprehensive
mechanistic
understanding
regulation.
Molecular
alters
architecture
manipulates
functional
groups/moieties
level,
introducing
various
permanent
or
reversible
dynamic
bonds
dissipative
energy.
usually
uses
monomers,
cross-linkers,
chains,
other
additives.
Structural
utilizes
casting
methods,
solvent
phase
regulation,
mechanochemistry,
macromolecule
chemical
reactions,
biomanufacturing
technology
construct
tailor
topological
structures,
heterogeneous
modulus
compositions.
We
envision
that
perfect
combination
may
provide
fresh
view
extend
exciting
new
perspectives
this
burgeoning
also
summarizes
recent
representative
applications
with
excellent
properties.
Conclusions
are
provided
from
five
aspects
concise
summary,
mechanism,
biofabrication
upgraded
applications,
synergistic
methodology.
Nature Communications,
Journal Year:
2024,
Volume and Issue:
15(1)
Published: Feb. 13, 2024
Abstract
Most
tough
hydrogels
are
reinforced
by
introducing
energy
dissipation
mechanisms,
but
simultaneously
realizing
a
high
toughness
and
low
hysteresis
is
challenging
because
the
structure
cannot
recover
rapidly.
In
this
work,
mechanical
performance
highly
entangled
double
network
without
fabricated,
in
which
physical
entanglements
act
as
primary
effective
crosslinking
first
network.
This
sliding
entanglement
allows
hydrogel
to
form
uniform
oriented
during
stretching,
resulting
tensile
strength
of
~3
MPa,
fracture
8340
J
m
−2
strain-stiffening
capability
47.5
90%
water
content.
Moreover,
almost
100%
reversibility
obtained
via
storage
based
on
entropy
loss.
The
not
only
overcomes
typical
trade-off
between
hydrogels,
more
importantly,
it
provides
an
insight
into
application
structures
high-performance
hydrogels.
Advanced Materials,
Journal Year:
2024,
Volume and Issue:
36(25)
Published: March 22, 2024
Abstract
Recently,
hydrogel‐based
soft
materials
have
demonstrated
huge
potential
in
robotics,
flexible
electronics
as
well
artificial
skins.
Although
various
methods
are
developed
to
prepare
tough
and
strong
hydrogels,
it
is
still
challenging
simultaneously
enhance
the
strength
toughness
of
especially
for
protein‐based
hydrogels.
Herein,
a
biomimetic
“salting
out—alignment—locking”
tactic
(SALT)
introduced
enhancing
mechanical
properties
through
synergy
alignment
salting
out
effect.
As
typical
example,
tensile
modulus
initially
brittle
gelatin
hydrogels
increase
940
folds
10.12
±
0.50
MPa
2830
34.26
3.94
MPa,
respectively,
increases
up
1785
14.28
3.13
MJ
m
−3
.
The
obtained
hold
records
previously
reported
gelatin‐based
hydrogel
close
tendons.
It
further
elucidated
that
effect
engenders
hydrophobic
domains,
while
prestretching
facilitates
chain
alignment,
both
synergistically
contributing
outstanding
properties.
noteworthy
SALT
demonstrates
remarkable
versatility
across
different
salt
types
polymer
systems,
thus
opening
new
avenues
engineering
strong,
tough,
stiff
Advanced Functional Materials,
Journal Year:
2023,
Volume and Issue:
33(42)
Published: Aug. 28, 2023
Abstract
The
advent
of
self‐powered
wearable
electronics
will
revolutionize
the
fields
smart
healthcare
and
sports
monitoring.
This
technological
advancement
necessitates
more
stringent
design
requirements
for
triboelectric
materials.
aerogels
must
enhance
their
mechanical
properties
to
address
issue
structural
collapse
in
real‐world
applications.
study
fabricates
stiff
nanocellulosic
with
multiscale
structures
induced
by
Hofmeister
effect.
aggregation
crystallization
polymer
molecular
chains
are
enhanced
effect,
while
ice
crystal
growth
imparts
a
porous
structure
aerogel
at
micron
scale.
Therefore,
exhibits
exceptional
stiffness,
boasting
Young's
modulus
up
142.9
MPa
specific
340.6
kN
m
kg
–1
,
remaining
undeformed
even
after
supporting
6600
times
its
weight.
Even
withstanding
an
impact
343
kPa,
highly
robust
sensors
fabricated
remain
operational.
Additionally,
sensor
is
capable
accurately
detecting
human
movements,
particularly
abnormal
fall
postures
detection.
provides
considerable
research
practical
value
promoting
material
broadening
application
scenarios
electronics.
Nature Communications,
Journal Year:
2024,
Volume and Issue:
15(1)
Published: May 24, 2024
Abstract
Ideal
hydrogel
fibers
with
high
toughness
and
environmental
tolerance
are
indispensable
for
their
long-term
application
in
flexible
electronics
as
actuating
sensing
elements.
However,
current
exhibit
poor
mechanical
properties
instability
due
to
intrinsically
weak
molecular
(chain)
interactions.
Inspired
by
the
multilevel
adjustment
of
spider
silk
network
structure
ions,
bionic
elaborated
ionic
crosslinking
crystalline
domains
constructed.
Bionic
show
a
162.25
±
21.99
megajoules
per
cubic
meter,
comparable
that
silks.
The
demonstrated
structural
engineering
strategy
can
be
generalized
other
polymers
inorganic
salts
fabricating
broadly
tunable
properties.
In
addition,
introduction
salt/glycerol/water
ternary
solvent
during
constructing
structures
endows
anti-freezing,
water
retention,
self-regeneration
This
work
provides
ideas
fabricate
stability
electronics.
Advanced Functional Materials,
Journal Year:
2023,
Volume and Issue:
34(6)
Published: Oct. 22, 2023
Abstract
Ionogels
are
compelling
materials
for
flexible
hybrid
electronics
owing
to
their
attractive
physical
properties
and
infinite
adjustability
of
chemical
structures.
However,
ionogels
must
be
sufficiently
strong
ensure
durability,
stability,
a
wide
range
strains
in
various
applications
make
electronic
systems
mechanically
compliant.
Inspired
by
the
hierarchical
structure
multiphase
substances
skin,
it
is
fabricated
several
transparent
(>90%)
ultra‐robust
(tensile
strength
>17
MPa,
toughness
>40
MJ
m
−3
,
elongation
≈300%)
via
situ
polymerization
polymers
with
different
binding
abilities
ionic
liquid
forming
soft
rigid
confinement
space.
This
strategy
can
also
applied
other
liquids
polymers.
Furthermore,
designed
ionogel
sensors
used
develop
wearable
intelligent
health
monitoring
system
capable
health‐related
physiological
signals,
such
as
temperature,
body
tremors,
wrist
pulse,
breathing,
gestures,
predicting
responding
emergencies,
which
will
pave
way
security
technology.
Advanced Materials,
Journal Year:
2024,
Volume and Issue:
unknown
Published: July 10, 2024
Abstract
Supramolecular
hydrogels
are
typically
assembled
through
weak
non‐covalent
interactions,
posing
a
significant
challenge
in
achieving
ultra
strength.
Developing
higher
strength
based
on
molecular/nanoscale
engineering
concepts
is
potential
improvement
strategy.
Herein,
super‐tough
supramolecular
hydrogel
by
gradually
diffusing
lignosulfonate
sodium
(LS)
into
polyvinyl
alcohol
(PVA)
solution.
Both
simulations
and
analytical
results
indicate
that
the
assembly
subsequent
enhancement
of
crosslinked
network
primarily
attributed
to
LS‐induced
formation
gradual
densification
strong
crystalline
domains
within
hydrogel.
The
optimized
exhibits
impressive
mechanical
properties
with
tensile
≈20
MPa,
Young's
modulus
≈14
toughness
≈50
MJ
m⁻
3
,
making
it
strongest
lignin‐PVA/polymer
known
so
far.
Moreover,
LS
provides
excellent
low‐temperature
stability
(<‐60
°C),
antibacterial,
UV‐blocking
capability
(≈100%).
Interestingly,
diffusion
ability
demonstrated
for
self‐restructuring
damaged
hydrogel,
3D
patterning
surfaces,
enhancing
local
freeze‐thaw
PVA
goal
foster
versatile
platform
combining
eco‐friendly
biocompatible
PVA,
paving
way
innovation
interdisciplinarity
biomedicine,
materials,
forestry
science.
Macromolecules,
Journal Year:
2024,
Volume and Issue:
57(6), P. 2746 - 2755
Published: Feb. 22, 2024
Breakthrough
to
the
extreme
properties
of
polymer
networks
relies
on
new
insights
into
their
molecular
dynamics.
Time-salt
concentration
superposition
has
been
discovered
in
polyelectrolyte
coacervate
systems,
proving
instrumental
tuning
mechanical
performance
hydrogels.
However,
time-salt
type
never
mentioned
existing
literature.
Herein,
we
reported
that
poly(methacrylamide)
(PMAm)
hydrogel
can
be
systematically
regulated
a
vast
range
by
treating
with
different
salts,
for
example,
Young's
modulus
tuned
from
10–2
103
MPa.
The
unusual
behavior
salt-stiffening
arises
salt-enhanced
phase
separation
network
and
subsequent
glassy
transition
polymer-rich
phase.
Rheological
results
demonstrate
dynamic
hydrogels
superposed
onto
"time-salt
type"
master
curves
salt
types
aligning
along
Hofmeister
series.
shift
factor
exhibits
correlation
mobility
water
molecules
as
revealed
low-field
nuclear
magnetic
resonance
spectroscopy.
A
polymer–water–salt
ternary
interaction
mechanism
was
proposed
elucidate
equivalent
behavior.
Guided
principle,
processing
strategy
brought
up
expand
property
limits
PMAm
hydrogel.
With
simply
switching
employed,
could
either
stiff
wear-resistant
material
akin
plastics
or
soft
flowable
gel
utilizable
recycling.