CORRELATION BETWEEN THE COMBINATORY ENTROPY OF POLYMER AND IDEAL LIQUID SOLUTIONS .2. TERNARY POLYMER-POLYMER SOLVENT AND BINARY POLYMER-POLYMER SYSTEMS

A semiempirical equation of combinatory entropy in ternary solutions containing two semiflexible polymers and flexible and semiflexible polymers in solvent has been derived, based on a previous equation for a binary polymer solution. The partial entropy of mixing for solvent, DELTAS(M,0), in the ternary system polymer (1)-polymer (2)-solvent (0) is expressed by: DELTAS(M,0)/k = -ln phi0 + a - 1 + ln[a/(a + b)] + b + k1phi1(2) ln{[r1(-1) + k1(1 - phi1](/a + b)} +k2phi2(2) ln{[r2(-1) + k2(1 - phi2)]/(a + b)} where a = phi0 + (phi1/r1) + (phi2/r2), b = k1phi1(1-phi1) + k2phi2(1-phi2), phi(i) is the volume fraction of component i, and k(i) is a constant characterizing the flexibility of polymer, for example k(i) = 0 for a flexible polymer and k(i) > 0 for a semiflexible polymer. Values of partial entropy of mixing for polymers, DELTAS(M,i), are evaluated in the ternary solution of two polymers with different flexibilities in solvent. The combinatory entropy in a binary polymer-polymer system is also discussed.