ACS Sustainable Chemistry & Engineering,
Год журнала:
2024,
Номер
12(17), С. 6494 - 6508
Опубликована: Апрель 12, 2024
Unsaturated
biopolymers
(e.g.,
natural
rubber
(NR))
are
highly
vulnerable
to
thermo-oxidative
degradation,
which
causes
premature
failure
of
NR
products.
As
an
indispensable
antioxidant
globally,
6PPD
(N-(1,3-dimethyl
butyl)-N′-phenyl-p-phenylenediamine)
is
employed
retard
the
aging
NR.
Unluckily,
and
6PPD-quinone
(an
oxidative
product
6PPD)
harmful
aquatic
human
life
and,
thus,
obviously
merit
their
replacement
with
sustainable
safer
antioxidants
for
environmental
protection.
This
study
explored
use
curcumin
NR-based
polymer
nanocomposites
(PNCs).
The
combined
experimental,
molecular
dynamics
(MD),
quantum
mechanics
(QM)
simulations
implemented
analyze
effect
isomeric
forms
on
protective
mechanism,
stability,
solubility,
dispersibility,
diffusion
in
matrix.
results
revealed
that
both
scavenged
free
radical
preferentially
via
a
hydrogen
atom
transfer
mechanism.
computed
transition
state
energies
show
curcumin's
enolic
form
(i.e.,
Curcumin
(E))
interacts
ROO.
(peroxy)
radicals
lower
barrier
energy
compared
could
protect
from
aging.
MD
have
shown
interfacial
interactions
at
NR-curcumin
interface
resulted
stronger
binding
energies,
thus
improving
solubility
dispersibility
mean
square
displacement
than
6PPD.
While
migration
necessary
replenish
concentrations
tire
surface,
higher
rate
may
cause
physical
loss
decrease
service
NR-PNCs.
Overall,
NR-PNCs
loaded
exhibited
improved
resistance
viscoelastic
performance
PNCs
made
Thus,
as
safe
antioxidant,
open
essential
avenue
toward
substantial
pollution
abatement
accumulated
waste
products
making
"Greener
NR-PNCs.″
Environmental Science & Technology Letters,
Год журнала:
2024,
Номер
11(4), С. 335 - 341
Опубликована: Март 25, 2024
N,N′-Substituted
p-phenylenediamines
(PPDs)
are
widely
utilized
as
rubber
antioxidants
and
emitted
into
the
environment
with
their
transformation
products
(TPs)
including
highly
toxic
6PPD-quinone.
However,
occurrence
of
PPDs
TPs
in
inconspicuous
oxidation
kinetics
under
natural
aging
conditions
remains
unclear.
Herein,
we
performed
a
field
survey
these
compounds
crumb
rubbers
from
40
school
artificial
turfs.
Twelve
were
frequently
detected
particles,
dominated
by
well-known
N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine
(6PPD)
N-isopropyl-N′-phenyl-1,4-phenylenediamine
(IPPD),
well
PPD-Qs.
One
pristine
material
was
chosen
to
simulate
process
examine
kinetics.
The
concentrations
all
powder
decreased
>
50%
within
4
days
aging,
much
faster
than
that
suggesting
size
effect
on
oxidation.
Different
had
distinct
degrees
both
simulated
experiments.
Besides
ozone,
found
high
temperature
could
induce
significantly
decay
particles
UV
exposure.
In
sum,
our
investigations
reveal
PPD-Qs
is
ubiquitous
chemically
specific
turf,
which
be
affected
particle
key
factors
controlling
Chemosphere,
Год журнала:
2024,
Номер
363, С. 142830 - 142830
Опубликована: Июль 11, 2024
The
environmental
ubiquity
of
tire
and
road
wear
particles
(TRWP)
underscores
the
need
to
understand
occurrence,
persistence,
effects
tire-related
chemicals
in
aquatic
ecosystems.
One
such
chemical
is
6PPD-quinone
(6PPD-Q),
a
transformation
product
antioxidant
6PPD.
In
urban
stormwater
runoff
6PPD-Q
can
exceed
acute
toxicity
thresholds
for
several
salmonid
species
being
implicated
significant
coho
salmon
losses
Pacific
Northwest.
There
critical
prevalence
across
watersheds
identify
habitats
heavily
affected
by
TRWPs.
We
conducted
reconnaissance
6PPD
surface
waters
United
States
from
sites
(N
=
94)
with
varying
land
use
(urban,
agricultural,
forested)
streamflow
better
stream
exposures.
A
rapid,
low-volume
direct-inject,
liquid
chromatography
mass
spectrometry
method
was
developed
quantitation
screening
Laboratory
holding
times,
bottle
material,
headspace,
filter
materials
were
investigated
inform
best
practices
sampling
analysis.
Glass
bottles
PTFE-lined
caps
minimized
sorption
borosilicate
glass
fiber
filters
provided
highest
recovery.
stable
at
least
5
months
pure
laboratory
solutions
75
days
°C
minimal
headspace
water
stormwaters.
Results
also
indicated
samples
be
frozen
extend
times.
not
detected
any
526
analyzed
there
no
detections
agricultural
or
forested
sites.
frequently
(57%,
N
90)
impacted
(45%,
276)
concentrations
ranging
0.002
0.29
μg/L.
concentrations,
above
lethal
level
salmon,
occurred
during
events.
This
highlights
importance
capturing
episodic
events
areas
near
ecologically
relevant
habitat
nursery
grounds
sensitive
species.
Environmental Science & Technology,
Год журнала:
2023,
Номер
57(49), С. 20813 - 20821
Опубликована: Ноя. 30, 2023
The
photochemical
degradation
pathways
of
6PPD-quinone
(6PPDQ,
6PPD-Q),
a
toxic
transformation
product
the
tire
antiozonant
6PPD,
were
determined
under
simulated
sunlight
conditions
typical
high-latitude
surface
waters.
Direct
resulted
in
6PPDQ
half-lives
ranging
from
17.5
h
at
20
°C
to
no
observable
over
48
4
°C.
Sensitization
excited
triplet-state
using
Cs
Environment International,
Год журнала:
2024,
Номер
186, С. 108609 - 108609
Опубликована: Апрель 1, 2024
Recently,
evidence
of
aromatic
amine
antioxidants
(AAs)
existence
in
the
dust
electronic
waste
(e-waste)
dismantling
area
has
been
exposed.
However,
there
is
limited
studies
investigating
occupational
exposure
and
toxicity
associated
with
AAs
their
transformation
products
(p-phenylenediamines-quinones,
i.e.,
PPD-Qs).
In
this
study,
115
42
hand
wipe
samples
collected
from
an
e-waste
recycling
industrial
park
central
China
were
analyzed
for
19
6
PPD-Qs.
Notably,
median
concentration
∑6PPD-Qs
(1,110
ng/g
1,970
ng/m2)
was
significantly
higher
(p
<
0.05,
Mann-Whitney
U
test)
than
that
∑6PPDs
(147
34.0
wipes.
Among
detected
analytes,
4-phenylaminodiphenylamine
quinone
(DPPD-Q)
(median:
781
ng/g)
1,4-Bis(2-naphthylamino)
benzene
(DNPD-Q)
156
ng/g),
particularly
prominent,
which
first
area.
Occupational
assessments
nuclear
receptor
interference
ability,
conducted
through
estimated
daily
intake
(EDI)
molecular
docking
analysis,
respectively,
indicated
significant
to
PPD-Qs
suggested
prioritized
Liver
X
receptors
(LXRs)
disruption
potential
PPDs
The
study
provides
considerable
levels
e-waste-related
underscores
importance
assessing
effects.
