Molecules,
Год журнала:
2024,
Номер
29(18), С. 4413 - 4413
Опубликована: Сен. 17, 2024
Novel
tetrafluoro-λ6-sulfanyl-containing
oligomers
prepared
by
visible
light-promoted
addition
of
1,4-(bis-chlorotetrafluoro-λ6-sulfanyl)
benzene
or
1,3-(bis-chlorotetrafluoro-λ6-sulfanyl)
to
either
1,4-diethynyl
the
1,3-diethynyl
isomers
form
hard,
stress
resistant
thin
films
on
spin
casting.
The
isomeric
were
utilized
establish
a
structure-function
relationship
for
mechanical
properties
from
oligomers.
Young’s
moduli
145-nm-thick
cured
could
reach
60
GPa.
measured
hardnesses,
between
1.57
and
2.77
GPa,
more
than
double
those
polymethyl
methacrylate
(PMMA)
films.
Curing
polymer
UV
irradiation
resulted
in
coatings
that
exhibited
remarkable
hardness
modulus
with
good
surface
adhesion
silicon.
Industrial & Engineering Chemistry Research,
Год журнала:
2024,
Номер
63(9), С. 3962 - 3974
Опубликована: Фев. 22, 2024
Free
radical
polymerization
initiated
under
visible
light
or
sunlight
remains
one
of
the
major
challenges
in
photopolymer
chemistry
area.
Because
low
intensity
modern
sources
(light-emitting
diodes,
LEDs)
and
mismatch
their
absorption
spectra
with
that
irradiation
sources,
commercial
usual
photoinitiators
often
exhibit
poor
efficiency
blue
sunlight.
In
this
work,
eight
naphtho[2,3-d]thiazole-4,9-dione
benzaldehyde-based
oxime
esters
were
developed
as
type
I
multicomponent
photoinitiating
systems
good
properties
region,
especially
at
405
450
nm.
Compared
to
benchmark
photoinitiator
(diphenyl(2,4,6-trimethylbenzoyl)phosphine
oxide,
TPO),
some
our
initiators
furnished
similar
better
photoinitiation
performance
than
reference
upon
exposure
LED@405
TPO,
most
newly
proposed
used
could
furnish
on
par
system
nm
LED@450
Among
interesting
results
study,
final
acrylate
function
conversions
be
obtained
during
free
trimethylolpropane
triacrylate
within
1
h
by
using
solar
when
combined
iodonium
salt
aromatic
amine.
Abstract
A
series
of
15
dyes
based
on
the
2‐phenylnaphtho[2,3‐
d
]thiazole‐4,9‐dione
scaffold
and
1
compound
2,3‐diphenyl‐1,2,3,4‐tetrahydrobenzo[
g
]quinoxaline‐5,10‐dione
are
studied
as
photoinitiators.
These
compounds
used
in
two‐
three‐component
high‐performance
photoinitiating
systems
for
free
radical
polymerization
trimethylolpropane
triacrylate
(TMPTA)
polyethylene
glycol
diacrylate
(PEGDA)
under
sunlight.
Remarkably,
conversion
TMPTA
can
reach
≈60%
within
20
s,
while
PEGDA
attains
a
96%
90
s.
To
delve
into
intricate
chemical
mechanisms
governing
polymerization,
an
array
analytical
techniques
is
employed.
Specifically,
UV–vis
absorption
fluorescence
spectroscopy,
steady‐state
photolysis,
stability
experiments,
quenching
cyclic
voltammetry,
electron
spin
resonance
trapping
(ESR‐ST)
collectively
contribute
to
comprehensive
understanding
photochemical
mechanisms.
Photoinitiation
capacities
these
determined
using
real‐time
Fourier
transformed
infrared
spectroscopy
(RT‐FTIR).
Of
particular
interest
revelation
that,
owing
superior
initiation
ability
dyes,
high‐resolution
3D
patterns
be
manufactured
by
direct
laser
write
(DLW)
technology
printing.
This
underscores
efficient
processes
newly
developed
both
artificial
natural
light
sources,
presenting
avenue
energy‐saving,
environmentally
friendly
conditions.
Angewandte Chemie International Edition,
Год журнала:
2024,
Номер
63(35)
Опубликована: Июнь 15, 2024
In
this
work,
six
benzothioxanthene-based
oxime
esters
were
employed
as
photoinitiators
for
photopolymerization
under
visible
light
(LED)
and
sunlight.
Their
abilities
to
behave
Type
I
by
mean
of
a
photocleavage
mechanism
but
also
in
multicomponent
photoinitiating
systems
with
an
iodonium
salt
(through
electron
transfer
mechanism)
both
explored
the
different
structures.
Due
their
broad
absorption
spectra
tailing
up
600
nm,
properties
systematically
tested
excitation
low-intensity
LED
at
wavelengths
405
nm
450
nm.
Additionally,
parallel
polymerization
tests
done
artificial
light,
investigated
solar
displayed
high
reactivity
France
(Western
Europe)
even
winter
conditions.
For
best
candidates
i.e.
most
reactive
structures,
direct
laser
write
experiments
carried
out,
evidencing
interest
these
Angewandte Chemie,
Год журнала:
2024,
Номер
136(35)
Опубликована: Июнь 15, 2024
Abstract
In
this
work,
six
benzothioxanthene‐based
oxime
esters
were
employed
as
photoinitiators
for
photopolymerization
under
visible
light
(LED)
and
sunlight.
Their
abilities
to
behave
Type
I
by
mean
of
a
photocleavage
mechanism
but
also
in
multicomponent
photoinitiating
systems
with
an
iodonium
salt
(through
electron
transfer
mechanism)
both
explored
the
different
structures.
Due
their
broad
absorption
spectra
tailing
up
600
nm,
properties
systematically
tested
excitation
low‐intensity
LED
at
wavelengths
405
nm
450
nm.
Additionally,
parallel
polymerization
tests
done
artificial
light,
investigated
solar
displayed
high
reactivity
France
(Western
Europe)
even
winter
conditions.
For
best
candidates
i.e.
most
reactive
structures,
direct
laser
write
experiments
carried
out,
evidencing
interest
these
