2 research outputs found
Polyhedral Oligomeric Silsesquioxane-Containing Thiol–ene Fibers with Tunable Thermal and Mechanical Properties
Polyhedral
oligomeric silsesquioxanes (POSS) are versatile inorganic–organic
hybrid building blocks that have potential applications as reinforcement
nanofillers, thermal stabilizers, and catalyst supports for metal
nanoparticles. However, fabrication of fibrous materials with high
POSS content has been a challenge because of the aggregation and solubility
limits of POSS units. In this paper, we describe a robust and environmentally
friendly fabrication approach of inorganic–organic hybrid POSS
fibers by integrating UV initiated thiol–ene polymerization
and centrifugal fiber spinning. The use of monomeric liquids in this
approach not only reduces the consumption of heat energy and solvent,
but it also promotes homogeneous mixing of organic and inorganic components
that allows integration of large amount of POSS (up to 80 wt %) into
the polymer network. The POSS containing thiol–ene fibers exhibited
enhanced thermomechanical properties compared to purely organic analogs
as revealed by substantial increases in residual weight and a factor
of 4 increase in modulus after thermal treatment at 1000 °C.
This simple fabrication approach combined with the tunability in fiber
properties afforded by tailoring monomer composition make POSS containing
thiol–ene fibers attractive candidates for catalyst supports
and filtration media, particularly in high-temperature and harsh environments
Solventless High Throughput Manufacturing of Poly(butylene terephthalate) Nanofibers
Nanofibers possess high surface area to volume ratios
and are particularly
attractive for a variety of applications including tissue regeneration,
drug delivery, fiber-reinforced composites, filtration, and protective
clothing. Though the production of nanofibers from common thermoplastic
polymers is relatively well-demonstrated, processing constraints have
limited high throughput manufacturing of nanofibers from high performance
polymers. This has in turn limited broad technological exploitation
of polymer nanofibers in areas such as hot chemical filtration or
high-performance lightweight composites for aerospace and defense
applications. We report here that nanofibers can be produced in a
solventless high throughput process from polymers such as polyÂ(butylene
terephthalate) (PBT) using a newly developed technology termed “Forcespinning”
that employs centrifugal force to attenuate fibers. Our investigations
also show that these nanofibers have a high crystallinity and enhanced
molecular orientation which is important for realizing desirable physical
and chemical properties of many high-performance polymer fibers