Effects of Polyol Types and Hard Segment Contents on the Crystallization of Thermoplastic Polyurethanes

열가소성 폴리우레탄의 결정화에 미치는 폴리올 종류 및 경질부 함량의 영향

  • Kim Sung Geun (Division of Environmental and Chemical Engineering, Chonbuk National University) ;
  • Li Ming Ji (Division of Environmental and Chemical Engineering, Chonbuk National University) ;
  • Ramesan M. T. (Division of Environmental and Chemical Engineering, Chonbuk National University) ;
  • Lee Dae Soo (Division of Environmental and Chemical Engineering, Chonbuk National University)
  • 김성근 (전북대학교 공과대학 환경화학공학부) ;
  • 이명걸 (전북대학교 공과대학 환경화학공학부) ;
  • ;
  • 이대수 (전북대학교 공과대학 환경화학공학부)
  • Published : 2005.03.01

Abstract

Effects of the polyol type and the hard segment content of thermoplastic polyurethane (TPU) on the crystallization of hard segments in TPUs were studied employing differential scanning calorimetry. Diols used for the preparation of TPUs were poly(tetramethylene ether glycol) (PTMEG), poly(propylene glycol) (PPG), polycaprolactone (PCL), poly(butylene adipate) (PBA) the molecular weights of which were 2000 and the hard segments contents of TPUs were $35\~44\;wt\%$. We found that crystallization of hard segments in TPUs were observed at higher temperatures and became faster with increasing hard segment contents of TPUs. The crystallization rate of TPU was also affected by the types of polyols used for the preparation of TPUs. It is postulated that lower miscibility of soft segments and hard segments results in higher crystallization rate and increase of cooling crystallization temperatures due to better hydrogen bending between hard segments in melts.

열가소성 폴리우레탄(thermoplastic polyurethane: TPU)의 제조에 사용한 폴리올 종류와 경질부 함량에 따른 TPU의 결정화 거동을 고찰하였다. TPU의 제조에 사용한 폴리올은 분자량이 2000인 poly(tetamethylene ether glycol) (PTMEG), poly(propylene glycol)(PPG) diol, polycaprolactone(PCL) diol, poly(butylene adipate)(PBA) diol을 사용하였으며, 경질부 함량은 $35\~44\;wt\%$였다. TPU의 경질부 냉각 결정화는 경질부 함량이 많을수록 고온에서 관찰되었다. TPU의 등온 결정화 속도는 경질부 함량이 많을수록 빠르고, TPU 제조에 사용한 폴리올 종류별로는 $PTMEG>PPG>PCI{\geqq}PBA$ 경향이 나타나, 연질부와 경질부의 상용성이 낮을수록 용융상태에서 경질부의 수소결합이 용이하고 결정화 속도가 빠르며, 냉각 결정화가 고온에서 나타나는 것으로 해석하였다.

Keywords

References

  1. G. Oertel, Polyurethane Handbook, 2nd Ed., Ch.2, Hanser Publishers, Munich, 1993
  2. S. Abouzahr, G. L. Wilkes, and Z. Ophir, Polymer, 23, 1077 (1982)
  3. M. Szycher, Szycher Handbook of Polyurethane, Ch.1, CRC Press, London, 1999
  4. C. Hepburn, Polyurethane Elastomer, 2nd Ed., Ch. 9, Elesvier Science Publishers, New York, 1992
  5. D. J. Martin, G. F. Meijs, G. M. Renwick, S. J. McCarthy, and P. A. Guantilake, J. Appl. Polym. Sci., 62, 1377 (1996)
  6. R. Mix, J. Gahde, H. Goering, and G. Schulz, J. Polym. Sci.; Part A: Polym. Chem., 34, 33 (1996)
  7. W. Tang, R. J. Farris, W. J. MacKnight, and C. D. Eisenbach, Macromolecules, 27, 2814 (1994)
  8. W. Tang, W. J. MacKnight, and S. Hsu, Macromolecules, 28, 4284 (1995)
  9. S. G. Kim and D. S. Lee, Macromol. Res., 10, 365 (2002)
  10. M. Avrami, J. Chem Phys., 7, 1103 (1939)
  11. B. Wunderlich, in Thermal Characterization of Polymeric Materials, E. A. Turi, Editor, Chapter 2, Academic Press, New York, 1997
  12. P. J. Yoon and C. D. Han, Macromolecules, 33, 2171 (2000)
  13. A. Gandica and J. Magil, Polymer, 13, 595 (1972)
  14. J. Magil and H. Li, J. Polym Sci., Ploym. Lett. Ed., 11, 667 (1973) https://doi.org/10.1002/pol.1973.130111101
  15. R. L. McKiernan, P. Sikorski, E. D. T. Atkins, S. P. Gido, and J. Penelle, Macromolecules, 35, 8433 (2002) https://doi.org/10.1021/ma011278u
  16. R. L. McKiernan, A. M. Heintz, S. L. Hsu, E. D. T. Atkins, J. Penelle, and S. P. Gido, Macromolecules, 35, 6970 (2002) https://doi.org/10.1021/ma0201274
  17. J. Magil, Rubber Chem. & Tech., 68, 507 (1995)
  18. A. Saiani, C. Rochas, G. Eeckhaut, W. A. Daunch, J. W. Leenslag, and J. S. Higgins, Macromolecules, 37, 1411 (2004)
  19. S. Velankar and S. L. Cooper, Macromolecules, 32, 395 (2000)