One of the keys to the EV tire prototyping project happens to be one of Molecular Rebar Design's core competencies: the dispersion of CNTs within the treated rubber.
"We are exploring different methodologies of retaining both the functionality of the CNTs and their dispersion capability, while ensuring that any product form developed is adequate for typical industrial rubber compounding and tire manufacturing processes," Krupp said.
Previously, poor dispersion inhibited the commercial use of CNTs.
Improvements were achieved through the invention and use of individualized CNTs, functionalized with hydroxyl and carboxyl groups, chemically bound with an organosilane and the rubber itself, Krupp said.
It is a gap that is bridged with MRD's unique ability to produce discrete, surface-tailored carbon nanotubes at scale, called Molecular Rebar.
Outside of rubber, the technology has found use in batteries, electronics, 3D-printing and medical applications.
"The strength of our intellectual property portfolio reflects MRD's focus on both the dispersion and chemical functionalization aspects," Krupp said.
In Phase I, MRD invented an organosilane functional carbon nanotube (Molecular Rebar).
While the nanotube is physically similar to MRD's commercial products in (very tiny) size, length and aspect ratio, the chemical functionality is "quite different from our commercial products offered to the rubber industry currently," Krupp said.
"The time frame of nine months in Phase I forced rapid innovation, where we utilized hypotheses and theories from other MRD business units like batteries, coatings and biotechnology to assist in development of the organosilane functionalization," Krupp said. "We believe (our) proprietary processes enable better performance, and we can envision future applications with different functionalities for improved elastomeric goods, parts and tires."
Krupp added that the use of the silane-MR can be further improved with other innovative products and processing techniques.
"We see the effects of Molecular Rebar, in general, as additive to other innovative technologies," he said.
In other words, MR can be used in conjunction with other legacy fillers, like carbon black and silica.
"We found the best use to be a little bit of both," he said. "We find that using a mixed structure of filler is most effective in terms of performance and cost."