Abstract
Experimental data of high pressure phase behavior between 35 °C and 105 °C and pressures up to 2,200 bar is presented for poly(d,l-lactic acid)(d,l-PLA) and poly(lactide-co-glycolide)15 (PLGA15), PLGA25, and PLGA50 in supercritical carbon dioxide, trifluoromethane (CHF3), chlorodifluoromethane (CHClF2), dichloromethane (CH2Cl2), and chloroform (CHCl3). d,l-PLA dissolves in carbon dioxide at pressures of 1,250 bar, in CHF3 at pressures of 500 to 750 bar, and in CHClF2 at pressures of 30–145 bar. As glycolic acid (glycolide) is added to the backbone of PLGA, the cloud point pressure increases by 36 bar/(mol GA) in carbon dioxide, 27 bar/(mol GA) in CHF3, and by only 3.9 bar/(mol GA) in CHClF2. PLGA50 does not dissolve in carbon dioxide at pressures of 2,800 bar, whereas it is readily soluble in CHClF2 at pressures as low as 95 bar at 40 °C. Cloud point behavior of d,l-PLA, PLGA15, and PLGA25 in supercritical carbon dioxide shows the effect of glycolide content between 35 °C and 108 °C. Also, the phase behavior for poly(lactic acid) — carbon dioxide-CHClF2 mixture shows the changes of pressure-temperature slope, and with CHClF2 concentration of 6 wt%, 19 wt%, 36 wt% and 65 wt%. The cloud-point behavior shows the impact of glycolide content on the phase behavior of PLA, PLGA15, PLGA25 and PLGA50 in supercritical CHClF2. A comparison was made between the phase behaviors of d,l-PLA and poly(l-lactide)(l-PLA) in supercritical CHF3. The phase behavior of CHF3 as a cosolvent for 5 wt% d,l-PLA-supercritical carbon dioxide system is presented for the effect being added 10 wt% and 29 wt% to CHF3 content.
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References
Benedetti, L., Bertucco, A. and Pallado, P., “Production of micronic particles of biocompatible polymer using supercritical carbon dioxide,” Biotechnol. Bioeng., 53, 232 (1997).
Benson, R. C. and Flygare, W. H., “The molecular zeeman effect in propene and comparison of the magnetic susceptibility anisotropies with cyclopropene and other small ring compounds,” Chem. Phys. Lett., 4, 141 (1969).
Bodmeier, R., Wang, H., Dixon, D. J., Mawson, S. and Johnson, K. P., “Polymeric microspheres prepared by spraying into compressed carbon dioxide,” Pharm. Res., 12, 1211 (1995).
Byun, H. S. and McHugh, M.A., “Impact of “Free” monomer concentration on the phase behavior of supercritical carbon dioxide-polymer mixtures,” Ind. Eng. Chem. Res., 39, 4658 (2000).
Conway, S. E., Byun, H. S., McHugh, M. A., Wang, J. D. and Mandel, F. S., “Poly(lactide-co-glycolide) solution in supercritical CO2, CHF3, and CHClF2,” J. Appl. Polym. Sci., 80, 1155 (2001).
Daubert, T. E. and Danner, R. P., Physical and thermodynamic properties of pure chemicals, Hemisphere Publishing, NY (1989).
Kim, J. H., Paxton, T. E. and Tomasko, D. L., “Microencapsulation of naproxen using rapid expansion of supercritical solutions,” Biotechnol. Prog., 12, 650 (1996).
Kirby, C. F. and McHugh, M. A., “Phase behavior of polymers in supercritical fluid solvents,” Chem. Rev., 99, 565 (1999).
Kuk, Y. M., Lee, B.C., Lee, Y.W. and Lim, J. S., “High-pressure phase behavior of poly(D,L-lactide) in chlorodifluoromethane, difluoromethane, trifluoromethane, and 1,1,1,2-tetraflrouoethane,” J. Chem. Eng. Data, 47, 575 (2002).
Lee, B.C., “Solvent power dependence of phase behavior of biodegradable polymers in high-pressure hydrofluorocarbons,” Korean J. Chem. Eng., 20, 542 (2003).
Lee, J.W., Kim, D.Y. and Lee, H., “Phase behavior and structure transition of the mixed methane and nitrogen hydrates,” Korean J. Chem. Eng., 23, 299 (2006).
Lele, A. and Shine, A. D., “Effect of RESS dynamics on polymer morphology,” Ind. Eng. Chem. Res., 33, 1476 (1994).
Mandel, F. S. and Wang, J. D. “Manufacturing of specialty materials in supercritical fluid carbon dioxide,” Inorg. Chim. Acta., 294, 214 (1999).
McHugh, M. A. and Krukonis, V. J., Supercritical fluid extraction: principles and practice, 2nd ed., Butterworth, Boston, MA (1994).
Meyer, G. and Toennies, J. P., “Determination of quadrupole moments of light hydrocarbon molecules from rotationally inelastic state scattering cross sections,” Chem. Phys., 52, 39 (1980).
Middleton, J.C. and Tipton, A. J., Synthetic biodegradable polymers as metical devices, Medical Plastics and Biomaterials Magazine, March/April (1998).
Park, J.Y., Lim, J. S., Park, K. H. and Yoo, K. P., “Phase behavior of poly(L-lactide) and polycaprolactone in various solvents at high pressure,” Korean Chem. Eng. Res., 42, 317 (2004).
Prausnitz, J. M., Lichtenthaler, R. N. and de Azevedo, E.G., Molecular thermodynamics of fluid-phase equilibria, 2nd ed., Prentice-Hall, Englewood Cliffs, NJ (1986).
Reid, R. C., Prausnitz, J. M. and Polling, B. E., The properties of gases and liquids, 4th ed., McGraw-Hill, New York, NY (1987).
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Byun, HS., Lee, HY. Cloud-point measurement of the biodegradable poly(d,l-lactide-co-glycolide) solution in supercritical fluid solvents. Korean J. Chem. Eng. 23, 1003–1008 (2006). https://doi.org/10.1007/s11814-006-0021-3
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DOI: https://doi.org/10.1007/s11814-006-0021-3