Study on phase behavior of binary polymer solution using ultrasonic technique

Phase behaviors of PS/cyclohexane and PS/methyl acetate binary solutions were investigated by using ultrasonic technique. Ultrasonic absorption of these solutions was increased with temperature and an upward peak was observed at a specific temperature. The peak temperature was considered to be the cloud-point, which was well agreed with reference data, and the phase diagram of UCST behavior could be determined from these points. Our experimental results showed that the ultrasonic absorption behavior of the proposed sample was affected by the molecular weight of polymer, polymer concentration, and solvent. The ultrasonic velocity was linearly decreased with temperature, however, there was no correlation between the cloud-point temperature and the ultrasonic velocity.