Engineers and other researchers are always striving to improve the lives of people who use technology as an integral part of their everyday lives.
Though evidence of this improvement is obvious in many cases, sometimes it’s the little things that can make a big difference.
In the case of polytetrafluoroethylene (PTFE), or Teflon, often these differences aren’t visible at all. Teflon is a synthetic fluoropolymer of tetrafluoroethylene that has applications across multiple industries - from acting as a lubricant in mechanical engineering to an anti-bacterial coating in the medical field. PTFE materials are also commonly used across the energy, aerospace, automotive and oil and natural gas industries.
While this material is probably best known for its use as a non-stick coating on cookware, there have been several new advancements surrounding the materialsince its accidental discovery in 1938.
Improvements into the use of the material will continue to grow, as the National Science Foundation (NSF) has recently awarded a $450,000 grant to materials science engineers and researchers at the University of Arkansas to study the effects of nanostructure material on the adhesion strength, mechanical properties and wear resistance of the PTFE coatings.
This grant will help further developments into creating highly wear-resistant PTFE applications, through the incorporation of polydopamine. The two compounds work together to improve wear-resistance by increasing the bonding strength between a polydopamine underlayer, the PTFE and the nanoparticles within the PTFE coatings themselves.
The end goal is to create a more durable coating, without diminishing underlying surface topography - a property essential in self-cleaning, anti-corrosion or anti-icing surfaces.
Polydopamine is a material with some interesting properties. It was first discovered in 2007 through research into adhesive proteins in mussels. By adjusting a material’s surface pH, it can be coated in a layer of polymerized dopamine. This changes the surface tension characteristics of a material, as discussed in the journal Advanced Materials back in 2011.
Modification of low surface energy materials such as Teflon or gold through the application of a nano-layer of polydopamine were early steps into the work of Min Zou, professor of mechanical engineering in the college of engineering and Jingyi Chen, assistant professor in the department of chemistry and biochemistry at the University of Arkansas.
“Obviously, PTFE is a great material with many wonderful applications,” said Zou. “But PTFE coatings are easily worn because of their poor adhesion to substrates, and this severely limits its applications.”
“After only a few uses, the Teflon becomes damaged,” Zou said. “Our project tries to solve that problem and increase the adhesion between Teflon and the substrate to make it more wear-resistant, and we do that by applying some mussel-inspired adhesive. We are looking at a range of applications because there’s a great potential for Teflon and it can have a great societal impact.”
“We are excited about it because the grant will enable us to engineer more durable surface for many applications and help us to train next generation in this field,” Chen added.
Their research and proposal were reviewed by experts in the field before the grant was awarded. “First, to have a good proposal you have to have novel ideas because the NSF only awards the ones that are cutting-edge and transformative to the viewer,” Zou said. “The award rate is very low, around 10 percent.”
The NSF has really taken notice of Zou’s work, having invested heavily into the University of Arkansas and the development of the statewide Center for Advanced Surface Engineering, where Zou serves as director.
With the future of nanoengineering in their hands, Zou and Chen may be at the forefront of something really big.