Modeling the Dispersibility of Single Walled Carbon Nanotubes in Organic Solvents by Quantitative Structure-Activity Relationship Approach

Abstract

The knowledge of physico-chemical properties of carbon nanotubes, including behavior in organic solvents is very important for design, manufacturing and utilizing of their counterparts with improved properties. In the present study a quantitative structure-activity/property relationship (QSAR/QSPR) approach was applied to predict the dispersibility of single walled carbon nanotubes (SWNTs) in various organic solvents. A number of additive descriptors and quantum-chemical descriptors were calculated and utilized to build QSAR models. The best predictability is shown by a 4-variable model. The model showed statistically good results (R2training = 0.797, Q2 = 0.665, R2test = 0.807), with high internal and external correlation coefficients. Presence of the X0Av descriptor and its negative term suggest that small size solvents have better SWCNTs solubility. Mass weighted descriptor ATS6m also indicates that heavier solvents (and small in size) most probably are better solvents for SWCNTs. The presence of the Dipole Z descriptor indicates that higher polarizability of the solvent molecule increases the solubility. The developed model and contributed descriptors can help to understand the mechanism of the dispersion process and predictorganic solvents that improve the dispersibility of SWNTs.

<strong>CORAL: The dispersion of SWNTs in different organic solvents</strong>

“…The dispersibility of SWNTs in a series of 29 different organic solvents taken in the literature [5,6]. The endpoint is decimal logarithm of dispersibility Cmax expressed in mg/mL.…”

“…The estimation of the domain has been done by scheme described in the literature [16]: the solvent with sum of defects for the SMILES less than average value of this parameter (for the training set) multiplied by 2: (6) [ Table 4, around here] One can see (Table 4) the distribution into the training, calibration, and validation sets has influence upon the domain of applicability, but this situation gives possibility to select preferable from the statistical point of view the distribution (minimum of the above-mentioned defect).…”

“…The abovementioned models related to fixed splits into the Mol2Net, 2015, 1(Section C), pages 1-9, Proceedings http://sciforum.net/conference/mol2net-1 training and validation sets, whereas models suggested in this work are checked up with three different splits. It is to be noted, different splits into the training and validation sets used in work [5] and in work [6].…”

“…The development of nanotechnology indicates that use of carbon nanotubes (CNTs), in general, and single-walled nanotubes (SWNTs), in particular, gives attractive possibilities for chemical technology [1], biochemistry [2], and medicine [3]. The dispersibility of SWNTs in various solvents is important physicochemical characteristics [4] from point of view of technology [5,6].…”

“…The theoretical approaches to predict of the endpoint for different solvents developed and described in the literature [5,6]. Apparently, however, similar studies based on the quantitative structure -property / activity relationships (QSPRs/QSARs) [7][8][9][10] be continued.…”