Effect of Molecular Weight on Phase Equilibrium in the Polystyrene-Poly(methyl methacrylate) System

Data on the solubility of oligomer polystyrene (PS) and poly(methyl methacrylate) (PMMA) of various molecular weights have been obtained. The binodal and spinodal curves of the phase state diagram with the upper critical solution temperature (UCST) are constructed through simulation within the framework of the Flory-Huggins theory. The influence of the molecular weight of polymers on the contribution to their mixing has been compared, and correlation curves have been plotted. The interaction parameters were calculated and the mixing thermodynamics of the components was evaluated. The largest contribution was made by the entropy component. Also, it has been shown using IR spectroscopy that there is no interaction between the functional groups of polystyrene and poly(methyl methacrylate) in a homogeneous mixture.

Automated summary

Data were obtained on the solubility of oligomer polystyrene (PS) and poly(methyl methacrylate) (PMMA) of various molecular weights. The phase state diagram with the upper critical solution temperature (UCST) was constructed using the Flory-Huggins theory. The influence of polymer molecular weight on mixing was compared and correlation curves were plotted. Interaction parameters were calculated and the mixing thermodynamics was evaluated, with the entropy component making the largest contribution. In addition, IR spectroscopy demonstrated no interaction between the functional groups of PS and PMMA in a homogeneous mixture.