Macromolecular Research

The Polymer Society of Korea (한국고분자학회)
권호 표지

Thermoresponsive Phase Transitions of PLA-block-PEO-block-PLA Triblock Stereo-Copolymers in Aqueous Solution

  • Lee, Hyung-Tak (Center for Advanced Functional Polymers, Department of Polymer Science and Engineering, Sungkyunkwan University) ;
  • Lee, Doo-Sung (Center for Advanced Functional Polymers, Department of Polymer Science and Engineering, Sungkyunkwan University)
  • Published : 2002.12.01
Download PDF
⟨ Previous Next ⟩

Abstract

A series of PLA-PEO-PLA triblock stereo-copolymers with varying PLA/PEO and L-DL-LA ratios were synthesized via ring opening pelymerizations. Aqueous solutions of these copolymers undergo thermo-responsive phase transitions as the temperature monotonically increases. Further study shows that there is a critical gel concentration (CGC), and also lower and upper critical gel temperatures (CGTs), at which the thermo-responsive phase transition occurs. The CGC and CGTs are affected by various factors such as block length, as well as the compositions of the PLA blocks and of the additives. In particular, the changes in the phase diagram produced by varying the L-/DL-LA ratio in the PLA blocks were determined to be mainly due to consequent stereo-regularity changes in the PLA blocks.

Keywords

References

  1. Nature v.373 G. Chen;A. S. Hoffman https://doi.org/10.1038/373049a0
  2. Nature v.374 R. Yoshida;K. Uchida;Y. Kaneko https://doi.org/10.1038/374240a0
  3. Thermoreversible Gelation of Polymers and Biopolymers J. M. Guenet
  4. Macromolecules v.27 Y. Zhuo;P. Simon;N. J. Deng;J. B. Ramound;D. Attwood;C. Booth https://doi.org/10.1021/ma00087a002
  5. Macromolecules v.29 Y. W. Yang;Z. Yang;Z. K. Zhou;D. Attwood;C. Booth https://doi.org/10.1021/ma951259i
  6. Macromolecules v.25 M. Malmsten;B. Lindman https://doi.org/10.1021/ma00046a050
  7. J. Parenteral Sci. & Technol. v.46 no.6 Z. Wout;E. A. Pec;J. A. Maggiore
  8. Atherosclerosis v.136 W. K. Palmer;E. E. Emeson;T. P. Johston https://doi.org/10.1016/S0021-9150(97)00193-7
  9. J. Biomed. Mater. Res. v.42 no.2 H. Suh;B. M. Jeong;R. Rathi;S. W. Kim https://doi.org/10.1002/(SICI)1097-4636(199811)42:2<331::AID-JBM19>3.0.CO;2-L
  10. Nature v.388 B. M. Jeong;Y. H. Bae;D. S. Lee;S. W. Kim https://doi.org/10.1038/42218
  11. J. Polym. Sci., Polym. Chem. Ed. v.37 no.6 B. M. Jeong;D. S. Lee;J. Shon;Y. H. Bae;S. W. Kim https://doi.org/10.1002/(SICI)1099-0518(19990315)37:6<751::AID-POLA10>3.0.CO;2-0
  12. Macromolecules v.32 B. M. Jeong;Y. H. Bae;S. W. Kim https://doi.org/10.1021/ma9908999
  13. J. Polym. Sci., Polym. Chem. Ed. v.37 no.13 S. W. Choi;S. Y. Choi;B. M. Jeong;S. W. Kim;D. S. Lee https://doi.org/10.1002/(SICI)1099-0518(19990701)37:13<2207::AID-POLA35>3.0.CO;2-0
  14. J. Control. Release v.64 Y. H. Bea;K. M. Huh;Y. G. Kim;K. H. Park https://doi.org/10.1016/S0168-3659(99)00126-1
  15. Polymer v.40 K. M. Huh;Y. H. Bae https://doi.org/10.1016/S0032-3861(98)00822-2
  16. J. Control. Release v.32 Y. X. Li;V. Christian;T. Kissel https://doi.org/10.1016/0168-3659(94)90050-7
  17. Korea Polym. J. v.8 no.5 Y. K. Sung;S. W. Kim
  18. J. Control. Release v.73 J. W. Lee;F. Hua;D. S. Lee https://doi.org/10.1016/S0168-3659(01)00297-8
  19. Macromol. Rapid Commun. v.22 M. S. Shim;S. W. Kim;H. J. Lee;T. Chang;D. S. Lee https://doi.org/10.1002/1521-3927(20010501)22:8<587::AID-MARC587>3.0.CO;2-8
  20. J. Biomed. Mater. Res. v.61 no.2 M. S. Shim;H. T. Lee;W. S. Shim;I. S. Park;H. J. Lee;T. H. Chang;S. W. Kim;D. S. Lee https://doi.org/10.1002/jbm.10164
  21. Biomaterials v.22 I. Molina;S. Li;M. B. Martinez;M. Vert https://doi.org/10.1016/S0142-9612(00)00192-7
  22. Aqueous Two Phase Partitioning B. Y. Zaslavsky
  23. Chemistry and Technology of Water-Soluble Polymers C. A. Finch