Thermal Properties and Molecular Weight Variations due to Thermal History in Segmented Polyurethane Copolymer Blends

세그먼트된 폴리우레탄 블렌드의 열이력에 따른 열적 성질과 분자량 변화

  • Cha, Yoon-Jong (BAlKSAN CO. LTD.) ;
  • Park, Dae-Woon (Department of Chemical Engineering, Inha University) ;
  • Kim, Hak-Lim (Department of Chemical Engineering, Inha University) ;
  • Lee, Han-Sup (Department of Textile Engineering, Research Institute of Polymer Science and Engineering, Inha University) ;
  • Mah, Souk II (Department of Textile Engineering, Research Institute of Polymer Science and Engineering, Inha University) ;
  • Choe, Soonja (Department of Chemical Engineering, Inha University)
  • 차윤종 ((주) 백산기술연구소) ;
  • 박대운 (인하대학교 화학공학과) ;
  • 김학림 (인하대학교 화학공학과) ;
  • 이한섭 (인하대학교 섬유공학과, 인하대학교 고분자공학연구소) ;
  • 마석일 (인하대학교 섬유공학과, 인하대학교 고분자공학연구소) ;
  • 최순자 (인하대학교 화학공학과)
  • Received : 1998.06.16
  • Accepted : 1998.11.02
  • Published : 1999.02.10

Abstract

The variations of the glass transition, melting peaks, molecular weight and its distribution (polydispersity index: PI) due to the annealing temperature and time have been investigated using the thermoplastic segmented polyurethanes (TPUs) and its blends based on the contents of hard segment. The position of the melting peak and its magnitude have been increased with the annealing temperature and time. This may be arised from the rearrangement of the microdomain structure due to the long-range or short-range segmental motion, the order-disorder transition of non-crystalline microphase, the variation of the domain size or the degree of disorder of crystalline structure by given different thermal histories. The annealing temperature and time affected the molecular weights and polydispersity : the number and weight average molecular weights were increased, while the polydispersity index (PI) deceased at certain temperatures : for TPU-35 at $135^{\circ}C$, for TPU-44 at $170^{\circ}C$ and for TPU-53 at $180^{\circ}C$. The temperatures which give the variations in molecular weights and in PIs are consistent with the annealing temperatures of which $T_3$ solely exists for each sample. Thus it is suggested that the chain dissosiation and recombination simultaneously occur at the above mentioned temperature for each sample.

Acknowledgement

Supported by : 교육부

References

  1. J. Macromol. Sci. v.B9 R. Bonart;L. Morbitzer;E. H. Muller
  2. J. Appl. Polym. Sci. v.27 T. K. Kwei
  3. Macromolecules v.19 L. M. Leung;J. T. Koberstein
  4. Macromolecules v.19 J. T. Koberstein;T. P. Russel
  5. Macromolecules v.20 H. S. Lee;Y. K. Wang;S. L. Hsu
  6. J. Polym. Sci., Polym. Phys. v.27 Z. S. Petrovic
  7. J. Polym. Sci., Polym. Phys. v.23 L. M. Leung;J. T. Koberstein
  8. Polymer v.22 J. W. C. Van Bogart;D. A. Bluemake and S. L. Cooper
  9. Polym. Eng. Sci. v.20 T. R. Hesketh;J. W. C. Van Bogart;S. L. Cooper
  10. J. Polym. Sci., Polym. Chem. Ed. v.46 N. Grassie;M. Zulfigar
  11. Eur. Polym. J. v.19 G. L. Marshall
  12. Polymer v.27 W. P. Wang;C. W. Macosco;S. T. Wellinghoff
  13. Macromolecules v.25 A. F. Galambos;J. T. Koberstein
  14. J. Polym. Sci., Polym. Phys. v.21 J. T. Koberstein;R. S. Stein
  15. J. Polym. Sci., Polym. chem. v.16 J. T. Koberstein;I. Gancarz;T. Clarke
  16. J. Polym. Sci., Polym. Chem. v.27 C. C. Greenwalt;J. H. Futreu