Abstracts Book - IMRC 2018

• SE2-O049
SCALABLE FABRICATION OF VERSATILE
POLYURETHANE/NANOTUBE COMPOSITES AND STUDY OF
STRUCTURE-PROPERTIES RELATIONSHIP
Yadienka Martinez Rubi 1 , Behnam Ashrafi 2 , Michael Jakubinek 1 , Shan Zou 3 , Michael Barnes 1 ,
Keun Su Kim 1 , Daesun Park 2 , Benoit Simard 1
1 National Research Council Canada, Security and Disruptive Technologies, Canada. 2 National
Research Council Canada, Aerospace, Canada. 3 National Research Council Canada,
Measurement Science and Standards, Canada.
One-dimensional nanomaterials such as carbon nanotubes (CNTs) and boron
nitride nanotubes (BNNTs) possess impressive physical, chemical and
mechanical properties and are promising reinforcement agents for the
development of enhanced multifunctional composites. We have fabricated
BNNT-polyurethane (TPU) and CNT-TPU sheets via a one-step filtration method
that uses a TPU solvent/nonsolvent combination. This solution method allows
for control of the composition and processing conditions, significantly reducing
both the filtration time and the need for large volumes of solvent to debundle
the nanotubes (NTs). The composition of the nanocomposites, which defines the
characteristics and properties of the material, can be precisely controlled.
Consequently, materials with tailorable properties (e.g. porosity, stiffness,
strength and toughness), shapes and functionalities can be fabricated. A
comparative study of the influence of BNNTs and CNTs on the tensile, electrical
and thermo-mechanical properties of NT/TPU composite sheets was
undertaken. The results showed that after incorporation of pristine nanotubes,
significant improvements in mechanical properties were achieved with both
nanomaterials. The trend in mechanical and electrical properties was
understood in terms of the NT−TPU interfacial interactions and morphological
changes occurring in the nanocomposite sheets as a function of increasing the
TPU content. At specifics NT-TPU weight ratios (e.g. 35:65 weight ratio for CNT-
TPU composites) a better NT exfoliation and optimal NT surface coverage was
achieved (optimized NT/TPU interface), which in turn lead to an optimal packing
of NT−TPU fibers. This optimal packing produced the highest improvement in
tensile properties and electrical conductivity in CNT-TPU sheets. On the other
hand, thermally conductive (5 W/m·K), electrically insulating sheets were
produced with BNNTs. The one-step solvent/nonsolvent process was shown to
be a scalable method for the fabrication of light-weight, high NT content
nanocomposite sheets. The process was successfully scaled common lab