DIFFUSION COEFFICIENTS IN POLYMER-SOLVENT SYSTEMS FOR HIGHLY CONCENTRATED POLYMER SOLUTIONS

• Main Authors: R.A. Reis, J. Vladimir Oliveira, R. Nobrega
• Format: Article
• Language: English
• Published: Brazilian Society of Chemical Engineering 2001-12-01
• Series: Brazilian Journal of Chemical Engineering
• Subjects: Vrentas/Duda model; free-volume theory; diffusion coefficient; experimental data; polymer-solvent systems
• Online Access: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0104-66322001000400003

The Vrentas/Duda proposal for the diffusion of polymer-solvent systems, which is based on the free-volume theory, was employed in correlating and predicting mutual diffusion coefficients in highly concentrated polymer solutions. It has been observed that the predictive version of the model is capable of qualitatively representing the experimental data, while the use of an adjustable parameter greatly improves the performance of the model. The systems studied were poly(vinyl) acetate-toluene and Neoprene-acetone, and a comparison between experimental data and calculated values from the Vrentas/Duda model is reported. A new experimental apparatus based on the sorption technique was built to provide reliable diffusivity data on the Neoprene-acetone system.