We report a detailed investigation of the effects of concentration and surface chemistry on the dispersion and rheological properties of single-walled carbon nanotubes in isophthalic unsaturated polyester, a prevalent thermoset resin. The growth of the SWNT network was shown by the concentration-dependent crossover parameters which provided an empirical basis for mastercurve scaling. To the author's knowledge, this is the first report of this type of colloidal scaling for dispersed SWNTs. Rheological percolation was found to occur at 0.106 vol % +/- 2% by using both power-law scaling and the concentration-dependent yield stress. The average effective hydrodynamic aspect ratio for the dispersed SWNTs was similar to 650. The SWNTs were found to be dispersed as small non-Brownian aggregates whose low shear aggregation behavior was strongly dependent on intermolecular interactions related to SWNT surface oxygen content.