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Mater Sci Nanotechnol 2017 | Volume 1 Issue 2
allied
academies
Nanomaterials and Nanochemistry
November 29-30, 2017 | Atlanta, USA
International Conference on
A
recently developed class of nano-structured, cage-
like silsesquioxanes, formally known as double-decker
shaped silsesquioxanes (DDSQ), offers the opportunity to
form hybrid polymers with silsesquioxane cages as a part of
the polymer backbone. Unlike functionalization of trisilanol
silsesquioxanes, functionalized DDSQs generate
cis
and
trans
isomers with respect to the Si-O core. Therefore, it is logical
to characterize physical and thermal properties of mixtures
with different ratios of
cis
and
trans
isomers. Moreover,
these characteristics are also relevant when reacting or
incorporating these isomers, or mixtures thereof, with
other molecules to form novel materials. In this study, three
aminophenyl DDSQs were synthesized. More specifically,
two meta-aminophenyl DDSQs, which were differentiated
according to the moiety attached to the D-Si (methyl
or cyclohexyl), and one para-aminophenyl DDSQ with a
methyl moiety were used. Chemical, physical, and thermal
characteristics were evaluated for individual isomers as
well as binary mixtures of different
cis
/
trans
ratios. Phase
diagrams representing solid-liquid melt equilibria of the
binary
cis
/
trans
mixtures were developed. Single crystal
X-ray diffraction data of isolated isomers helped to interpret
the phase behavior. A specific application was chosen
to demonstrate advantages of using these DDSQ in high
performance thermosetting oligoimides over their organic
counterparts. Specifically, they exhibited advantages in
areas of liquid to solid
trans
ition and viscosity, which greatly
expand the processing window. Additionally, they improve
oxidative stability and reduce moisture uptake which
provided a significant enhancement for service reliability.
e:
leea@egr.msu.eduAminophenyl double-decker shaped silsesquioxanes: Physical, thermal characterization and applications
Andre Lee
Michigan State University, USA