Polymers,
Journal Year:
2024,
Volume and Issue:
16(13), P. 1889 - 1889
Published: July 2, 2024
Polyurethane
(PU)
is
among
the
most
universal
polymers
and
has
been
extensively
applied
in
many
fields,
such
as
construction,
machinery,
furniture,
clothing,
textile,
packaging
biomedicine.
Traditionally,
main
starting
materials
for
PU,
polyols
deeply
depend
on
petroleum
stock.
From
perspective
of
recycling
environmental
friendliness,
advanced
PU
synthesis,
using
diversified
resources
feedstocks,
aims
to
develop
versatile
products
with
excellent
properties
achieve
transformation
from
a
fossil
fuel-driven
energy
economy
renewable
sustainable
ones.
This
review
focuses
recent
development
synthesis
modification
by
extracting
value-added
monomers
waste
natural
bio-based
polymers,
recycled
polymers:
polyethylene
terephthalate
(PET),
polycarbonate
(PC);
biomaterials:
vegetable
oil,
lignin,
cashew
nut
shell
liquid
plant
straw;
biomacromolecules:
polysaccharides
protein.
To
design
these
polyurethane
formulations,
it
essential
understand
structure-property
relationships
polyols.
In
word,
this
bottom-up
path
provides
material
approach
printing
packaging,
well
biomedical,
building
wearable
electronics
applications.
Chemical Science,
Journal Year:
2024,
Volume and Issue:
15(25), P. 9397 - 9407
Published: Jan. 1, 2024
Life-cycle
assessment
can
better
capture
the
impacts
of
plastics
recycling
by
expanding
beyond
greenhouse
gases
to
include
fossil
carbon
balances,
net
diversion
waste
from
landfill,
and
avoided
release
plastic
pollution
environment.
Catalytic
upcycling,
a
process
for
the
valorization
of
plastic
waste
toward
value-added
products,
has
garnered
attention
as
promising
approach
to
management.
This
study
investigated
aromatic
product
distribution
from
thermal
and
catalytic
fast
pyrolysis
PET
using
Py-GC-MS/FID.
Thermal
(550–800
°C)
revealed
that
acetophenone
increases
sharply
with
rising
temperatures,
becoming
dominant
at
800
°C.
was
conducted
three
zeolites
(HZSM-5,
HBeta,
HY).
HBeta
yielded
highest
benzene,
while
HZSM-5
exhibited
total
yields
toluene,
ethylbenzene,
xylene,
styrene,
naphthalene.
HY
significantly
promoted
production
acetophenone,
new
finding
further
by
vinyl
benzoate
ethylene
dibenzoate
model
compounds.
A
formation
route
proposed,
involving
homolysis
Calkyl–O
bond
in
PET,
rearrangement,
decarbonylation.
Further,
effects
various
reaction
conditions,
including
catalyst/feedstock
ratios,
SiO2/Al2O3
mode
operation
(in
situ
vs
ex
situ),
on
selectivity
products
were
systematically
explored.
The
findings
this
work
contribute
application
technology
upcycling
oxygen-containing
organic
solid
waste.
