Vapor‐liquid equilibria for polybutadiene and polyisoprene solutions

Vapor‐liquid equilibria in binary solutions of hydrocarbons (n‐hexane, benzene, toluene, cyclohexane) and chlorinated methanes [carbon tetrachloride (CCl4), chloroform (CHCl3), and dichloromethane (CH2Cl2)] in polybutadiene (PBD) and polyisoprene have been determined at 23.5°C by using the piezoelectric sorption method. The weight‐fraction activity coefficient of solvent (a1/w1) in cis‐PBD (98% cis‐1,4 addition) and random cis‐trans‐PBD (r‐PBD, 34.3% cis‐1,4 addition; 54.3% trans‐1,4 addition; 11.4% vinyl‐1,2 addition) are almost equal for CCI4, CHCI3, CH2CI2, benzene, and toluene solutions, while the values of a1/w1 in n‐hexane and cyclohexane solutions in cis‐PBD are larger than those in r‐PBD solutions. The values of a1/w1 for solutions of hydrocarbons and chlorinated methanes in cis‐1,4 polyisoprene (95% cis‐1,4 addition) have been compared with those for cis‐PBD.