“…This solubility parameter can be determined experimentally or calculated based on the molecular structure, i.e., by the method reported by Fedors . ShellSolTD is a mixture of alkanes, and therefore, ShellSolTD was replaced by heptane, for which δ = 15.2 J 1/2 m –3/2 , and the heptane/toluene ratio was adjusted to vary the δ value between 15.2 and 18.2 J 1/2 m –3/2 (i.e., the δ value of toluene). , The calculated δ values of VPE (δ = 19.0 J 1/2 m –3/2 ) and of pVPE (δ = 21.1 J 1/2 m –3/2 ) are higher than those of styrene (17.8 J 1/2 m –3/2 ) and PS (δ = 17.4–19.0 J 1/2 m –3/2 ); , thus, the δ of a suitable porogen mixture (δ mix ) is also expected to be higher than the δ mix of the porogen used for the suspension polymerization of PS. Volumetric mixtures of 75:25 and 50:50 heptane and toluene with δ mix values of 15.6 and 16.9 J 1/2 m –3/2 , respectively, did dissolve VPE and resulted in the formation polymeric beads (Table , entries 1 and 2).…”