SouthWest NanoTechnologies has expanded its SMW specialty multi-wall carbon nanotube (MWCNT) line with two new grades, SMW200 and SMW210, which can be utilized as additives to increase lithium ion battery cathode performance and electrical conductivity of polymer compounds.
The new grades have shown lower percolation threshold and easier dispersions when compared to other MWCNTs in several customer thermoplastic compound assessments, thus enabling electrostatic discharge performance even at lower filler loadings when compared to carbon black or other MWCNTs, in various polymers. Their lower percolation threshold reduces the deterioration of a polymer’s physical properties, a typical issue in heavily loaded compounds, and their higher conductivity at equivalent loading widens application areas for conductive polymers.
SouthWest NanoTechnologies synthesized SMW200 and SMW210 using the CoMoCAT technique. Both materials comprise the same defect-free, less entangled, ultra-pure CNT. SMW200 is a high-purity grade with 96%+ CNT purity. The company can provide even higher purity research grades based upon request. SMW210 is a produced grade with 70%+ CNT purity. The remaining content is largely metal oxides utilized in the catalyst. The price of SMW210 is much lower as it does not involve post-synthesis purification. SMW210 features a hybrid structure where metal-oxide particles are bonded to the CNT, thus providing better dispersion at a very low cost.
There is a difference in performance between SMW200 and SMW210 in thermoplastic compound with respect to percolation, conductivity, and ease of dispersion. However, majority of customers prefer SMW210 for its lower cost. The use of SMW200 as a substitute for carbon black in lithium ion battery cathodes has been demonstrated. SWM200’s very low loadings of 1 wt % have demonstrated superior low temperature performance, lower heat build-up, higher capacity and doubled cycle life.
Source: http://www.swentnano.com/