A rheometer for concentrated polymer solutions containing volatile solvents

A new rheometer cell and integrated transducer, which is capable of performing both steady state and dynamic measurements in a controlled environment and at elevated temperatures and pressures, is described here. This cell mounts onto either the Rheometrics Mechanical Spectrometer or the Rheometrics System Four rheometer and utilizes the wide range of shear rates and frequencies available on these instruments. The unique capabilities of the rheometer and cell permit measurement of the rheological properties of concentrated polymer, solutions containing volatile solvents at temperatures above the normal boiling point of the solvent. The steady shear and dynamic properties of several polystyrene/ethylbenzene solutions having polymer concentrations greater than 50 wt percent are presented to demonstrate the performance of the rheometer.