Elastomer-based electronics components and accessories, cables and wires, industrial equipment, safety wear, tires, and many other specific rubber and silicone applications stretch the requirements and expectations for conductive additives. But the issue of how to combine conductivity with improvements in the mechanical properties of elastomers remained difficult for the industry until recently.
More than 430 delegates from 22 countries gathered in Shanghai for the annual Nanoaugmented Materials Industry Summit (NAUM), organised by OCSiAl. During the two-day event companies such as Lanxess, Elkem Silicones, Prysmian Group, KraussMaffei, Orient Energy & Technology shared their experience in applied nanotechnology.
Graphene nanotubes, also known as single wall carbon nanotubes, bring significant added value to elastomer applications, thanks to their unique combination of superior conductivity and ability for colouration, while not requiring any changes to production technology and with no drawbacks in terms of material properties. At NAUM 2018, Shanghai KraussMaffei Machinery shared the results they have achieved in injection moulding of Elkem Silicones LSR compounds enhanced with nanotubes.
“The solution is a concentrate of Tuball single wall carbon nanotubes, produced by OCSiAl. It is possible to put just 1–1.5 % in compounding with LSR. It does not have a negative effect on processing on our PX electric Injection molding machine. The result of the final part is brilliant,” shared Stefan Fenske, head of business development and technology management.
As was unveiled at the Summit, graphene nanotubes are already used in silicone cable accessory manufacturing, where stable conductive properties play a critical role. “Conductive silicone coating is a key material for high and medium-voltage shielding accessories. Carbon black powder limits the conductivity level, and with single wall carbon nanotubes we can achieve the required conductivity without carbon migration to the surface of material,” Andy Gan, CEO DM-Star New Material Technology said, explaining why his company has switched to nanotubes.
Another example of how the industry can benefit from nanotechnology was demonstrated at NAUM 2018 by Orient Energy & Technology. “56% of screw drilling failures are due to the failure of the rubber polymer, and result in companies losing oil,” Zhihuai Hu, Rubber Engineer said. “By adding single wall carbon nanotubes to NBR, we obtain significant improvements: the modulus of the drill’s stator rubber increased by 30%, so output torque increased by 30% with a 20% improvement in DIN abrasion resistance. That means the drilling speed can be increased by more than 20%, shortening the drilling time and having less impact on the environment.”
Kasen Duan from Elkem Silicones has highlighted that due to their functionality in low working dosages, graphene nanotubes ensure profitability. Graphene nanotubes continue to produce exciting results for elastomer manufacturers, and the number of those who have attained the benefits of their use is growing explosively.
Competition is fierce in the world’s largest developed markets, and manufacturers are constantly searching for the most innovative technologies to boost their materials’ performance. Graphene nanotubes provide the solution for many companies as they develop next-generation products. “We have to think in new ways about size, properties, and possibilities with nanomaterials,” said Dr. Martin Wildemann, research scientist at Lehmann & Voss & Co, when discussing advanced techniques in processing nanomaterials. Calling this a “Nano Wonderland,” he shared ways to bring the unique additive into the real world in developing products for the market.
The rising complexity of the overall market forces manufacturers to be agile and innovative in order to be competitive. Strong potential for new business is provided by single wall carbon nanotubes, as it was stated by Ivica Kolaric, General Manager Business Unit Process Industries, Fraunhofer IPA.
“Carbon nanotube products are a special and unique material,” said Bruna Calza, global product manager of Lanxess. “We benefit from their extraordinary electrical conductivity and mechanical enhancement, which motivated us to develop materials using them. Carbon nanotubes mean innovation, and we are constantly putting our efforts in these materials because they are the future of our business.”
Source: Dr. Gupta Publishing