Researchers from Dresden University of Technology in cooperation with Fraunhofer IWS conducted a series of tests to measure dependency of specific resistivity on the additive concentration of SW- and MWCNTs in samples of basic polymer DowCorning Sylgard 184.
One of the samples contained single wall carbon nanotubes provided by OCSiAl under the brand TUBALL™.
The researchers concluded: TUBALL™ single wall nanotubes are superior in every way to multi-walled nanotubes. This is particularly well illustrated by the gap 0.0-0.1% (on the graph), where the resistivity of the sample with multi-walled nanotubes increases, while TUBALL™ nanotubes show a resistivity drop from 10^12 to 10^5 (lower is better).
This also means higher concentrations of multi-walled nanotubes are required to reach the same values of resistivity that can be obtained with TUBALL™. For multi-wall nanotubes the concentration required is 1.3%, which is 13 times higher than needed with TUBALL™, and for the SWCNTs from Fraunhofer IWS the concentration required is 0.4%, which is 4 times higher than the corresponding value for TUBALL™. What these results mean is that to achieve the same benefit you would need significantly less TUBALL™ when compared to other types of carbon nanotubes.
The researchers also noted that the positive effects for other properties in other samples are much stronger with TUBALL™.
The demand for polymers and adhesives with specific properties for industrial applications is growing substantially. Features like low specific resistance are crucial for the efficient applications and producibility. One of the ways to achieve the required values is to modify the basic polymer with CNT-based additives, and TUBALL™ provides the most optimal results.
These results show the high potential of TUBALL™ in the production of modified elastic conductive paths, conductive sealing and jointing materials, and also for electroactive polymers.