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Supercritical Gas Solvents as Viscosity-Reducing Agents for Thermoplastic Composite Processing
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Abstract
Solubility and viscosity predictions for solutions of a thermoplastic polymer with several supercritical gases indicate that significant viscosity reduction and solubility are achieved when the processing conditions are closely matched with the critical properties of the dissolved gas. For the solubility predictions, PVT behavior was modeled by the lattice theory based Sanchez - Lacombe equation-of-state (EOS). Viscosity was estimated by employing the Kelley - Bueche free volume theory coupled with the volumetric calculations of the EOS. Unlike conventional solvents, supercritical solvents add significant free volume to supercritical gas / polymer mixtures; this added free volume provides remarkable viscosity reduction. Viscosity reductions of up to two orders of magnitude are predicted for a supercritical gas / polymer system, compared to the undiluted polymer when the critical temperature for the supercritical gas is matched to the polymer processing temperature. The solubility and viscosity reduction results offer much encouragement for the development of supercritical gases as polymer processing agents.
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Citation
Garg, A., Gerhardt, L., Manke, C., and Gulari, E., "Supercritical Gas Solvents as Viscosity-Reducing Agents for Thermoplastic Composite Processing," SAE Technical Paper 930173, 1993, https://doi.org/10.4271/930173.Also In
References
- Wang, W. V. Kramer, E. J. Sachse, W. H. J. Poly. Sci. Poly. Phys. Ed. 20 1371 1982
- Brennecke, J. F. Eckert, C. A. AlChE J 35 9 1409 1989
- Daneshvar, M. Gulari, Es. ACS Symposium Series: Supercritical Fluid Science and Technology 72 406 1989
- Daneshvar, M. Kim, S. Gulari, Es. J. Chem. Phys. 94 2124 1990
- Sanchez, I. C. Lacombe, R. H. J. Phys. Chem. 80 21 2352 1976
- Sanchez, I. C. Lacombe, R. H. Macromolecules 11 6 1145 1978
- Williams, M. Landel, R. Ferry, J. J Am. Chem. Soc. 77 3701 1955
- Kelley, F. Bueche, F. J. Polym. Sci. 50 549 1961
- Gerhardt, L. J. Garg, A. Bae, Y. C. Manke, C. W. Gulari, Es Moldenaers P. Keunings R. Proc. Xlth Int. Congress on Rheology Brussels, Belgium August 17-21 Elsevier Sci. Pub. 348 1992
- Garg, A. Gerhardt, L. Gulari, Es. Manke, C. W. McHugh M. 2nd International Symposium on Supercritical Fluids Boston, MA May 20-22 John Hopkins Univ. Baltimore 233 1991
- Haward, R. N. Breuer, H. Rehage, G. Poly. Letters 4 375 1966