More than 400 delegates from 22 countries around the globe gathered in Shanghai for the annual Nanoaugmented Materials Industry Summit (NAUM), organized by OCSiAl. During the two-day event which concluded on November 1, 2018, LANXESS, Elkem Silicones, Prysmian Group, KraussMaffei, Orient Energy & Technology and others shared their first-hand experience in applied nanotechnology.
Elastomer-based electronics components and accessories, cables and wires, industrial equipment, safety wear, tyres, 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.
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 impressive results they have achieved in injection molding 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.

OCSiAl’s TUBALL graphene nanotubes

OCSiAl’s TUBALL graphene nanotubes are rapidly gaining ground in customer-oriented applications with high-performance requirements. One remarkable example is PU discs in cleaning pigs for industrial pipelines. To avoid explosions and fires while also preventing static noise and improving diagnostic accuracy, manufacturers of cleaning pigs are replacing ammonium salts as an anti-static agent with TUBALL MATRIX 202. In addition to a permanent and stable resistivity level of 10^7–10^5 Ω·cm, the preliminary results have shown a 30% reduction in the rate of equipment failure.
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.

Benefit from nanotechnology

Another impressive 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.