Solubility of octane, cyclopentane, cyclohexane, benzene, toluene, ethylbenzene and p-xylene in cis-1,4-polyisoprene, polyisobutylene, poly(n-butyl methacrylate), and poly(vinyl acetate) were measured by the piezoelectric quartz crystal microbalance method at four temperatures (293.2, 313.2, 333.2, and 353.2) K. In this work, four quartz crystals were installed in an equilibrium cell, which enables multiple solubility measurements. Estimated uncertainties of measured variables were +/-0.05 K for temperature, +/-0.009 for activity, and +/-0.002 for mass fraction. The accuracy of the method was confirmed by comparison with literature data. The activities obtained were correlated by the UNIQUAC equation with an overall AAD of 4.1%.