PC-SAFT based group contribution method for binary interaction parameters of polymer/solvent systems

摘要

Based on the PC-SAFT equation of state, a group-contribution method is developed for the determination of binary interaction parameters (k_(ij)) between polymers and solvents (GCM-k_(ij)). Applying simple geometric combination rules, the k_(ij) values can be calculated from binary interaction parameters between polymer groups and solvent groups (k_(ps)). 80 different k_(ps) values allow the calculation of a k_(ij) for polymer/solvent systems with polymers consisting of CH_3, 〉CH_2, 〉CH_(2,HDPE), 〉(CH), 〉C〈, 〉CH_(Ar), 〉C_(Ar) and (CO)O groups and solvents containing CH_3, 〉CH_2, 〉(CH), 〉CH_(2,Cyclo), 〉(CH)_(Cyclo), CH_(2,alkene), (CH)_(alkene), 〉CH_(Ar), 〉C_(Ar), O, 〉CO and (CO)O groups. Using earlier-published group-contributions for polymer parameters (Peters et al. [2,3]) in combination with the proposed GCM-k_(ij) for polymer/solvent systems allows for predicting liquid-liquid phase equilibria, vapor-liquid phase equilibria and excess enthalpies of binary polymer/solvent and copolymer/solvent as well as ternary polymer/solvent 1/solvent 2 systems in good agreement with experimental data.