Article
  • Structural Charaeteristics and Polymerization Properties of Polysiloxane Bridged ansa-Metallocene as a Model Compound for the Heterogenized Metallocene at Silica Surface
  • Noh SK, Lee CS, Lee DH, Yoon KB, Kang KS
  • 실리카에 불균일화된 메탈로센 촉매의 모델화합물로서 합성된 Polysiloxane Bridged ansa-Metallocene의 구조특성과 중합특성
  • 노석균, 이철수, 이동호, 윤근병, 강경석
Abstract
Three polysiloxane bridged ansa-metallocenes, tetramethyldisiloxanediylbis(cyclopentadienyl)zirconium dichloride, [TMDSCp2]ZrC12, hexamethyltrisiloxanediylbis(cyclopentadienyl)zirconium dichloride, [HMTSCp2]ZrC12, and tetramethyldisiloxanediylbis(cyclopentadienyl)zirconium dimethylate, [TMDSCp2]ZrMe2, have been prepared and their polymerization studies have been pursued as a model compound for the heterogenized metallocene onto silica surface. Polymerization results show that [TMDSCp2]ZrCl2 having disiloxane (Si-O-Si) linkage between two Cp has unexpectedly high activity for ethylene polymerization while [HMTSCp2]ZrC12 having trisiloxane (Si-O-Si-O-Si) linkage between two Cp does not polymerize ethylene at all. The above results can be rationalized by structural characteristics of [TMDSCp2]ZrC12. It turns out that [TMDSCp2]ZrC12 has an wide active site around metal center due to the big angle of Cl-Zr-Cl, which consequently does not exert much steric disturbance during monomer coordination and insertion. Another feature to be noted is molecular weight of the polyethylene from disiloaxne bridged metallocene is extremely sensitive to the change of polymerization temperature.

실리카 표면에 불균일화된 메탈로센의 모델화합물로서 세 가지의 polysiloxane bridged ansa-metallocene인 tetramethyldisiloxanediylbis(cyclopentadienyl)zirconium dichloride, [TMDSCp2]ZrC12와 hexamethyltrisiloxanediylbis(cyclopentadienyl)zirconium dichloride, [HMTSCp2]ZrC12, 그리고 [TMDSCp2]ZrCl2를 Grignard 시약으로 메틸화시킨 tetramethyldissiloxanediylbis(cyclopentadienyl)zirconium dimethylate, [TMDSCp2]ZrMe2를 합성하고 이들의 에틸렌 중합이 수행되었다. 중합결과 disiloxane bridge를 가진 [TMDSCp2]ZrC12 화합물은 알려진 다른 어떤 촉매보다 높은 활성을 보였으나 trisiloxane bridge를 가진 촉매는 활성을 나타내지 않았다. 이것은 disiloxane bridge를 가진 화합물의 구조적인 특징에 기인된 결과로서 해석될수 있다. [TMDSCp2]ZrC12는 ethylene이나 trimethylene bridge를 가진 화합물보다 휠씬 큰 Cl-Zr-Cl 각도를 가지고 있을 뿐 아니라 활성점이 열려진 구조를 가지고 있으므로 단량체의 배위와 삽입시에 입체적인 방해가 작을 것으로 이해된다. 또한 disiloxane bridge를 가진 메탈로센은 중합온도에 따라 분자량이 매우 민감하게 변하는 특징을 보였다.

References
  • 1. Proceedings of International Metallocene Polymers: Metallocene '95, 26-27 April, 1995, Brussel, Belgium (1995)
  •  
  • 2. Thayer AM, Chem. Eng. News, Sep., 11 (1995)
  •  
  • 3. Proceedings of Metcon'95, July, 1995, Houston, Texas (1995)
  •  
  • 4. Brintzinger HH, Fischer D, Mulhaupt P, Waymouth RM, Angew. Chem.-Int. Edit., 34, 1143 (1995)
  •  
  • 5. Noh SK, Polym. Sci. Technol., 5(3), 189 (1994)
  •  
  • 6. Sinn H, Kaminsky W, Adv. Org. Chem., 18, 99 (1980)
  •  
  • 7. Halterman RL, Chem. Rev., 92, 965 (1992)
  •  
  • 8. Davis BR, Bernal I, J. Org. Chem., 30, 75 (1971)
  •  
  • 9. Razavi AProceedings of the 3rd International Business Forum on Specialty Polyolefins SPO'93, p. 107, Sep. 21-23 (1993)
  •  
  • 10. Bonini F, Fraaije V, Fink G, J. Polym. Sci. A: Polym. Chem., 33(14), 2393 (1995)
  •  
  • 11. Chein JCW, He D, J. Polym. Sci. A: Polym. Chem., 29, 1603 (1991)
  •  
  • 12. Soga K, Shiono T, Kim HJ, Macromol. Chem., 194, 3499 (1993)
  •  
  • 13. Collins S, Kelly WM, Holden DA, Macromolecules, 25, 1780 (1992)
  •  
  • 14. Kaminsky W, Renner F, Winkelbach HProceedings of Metcon'94, High Melting Polypropylene by Supported Metallocene Catalysts, April 15 (1994)
  •  
  • 15. Soga K, Kaninaka M, Macromol. Rapid Commun., 13, 211 (1992)
  •  
  • 16. Soga K, Kaminakam M, Macromol. Chem., 194, 1745 (1993)
  •  
  • 17. Lee DH, Yoon KB, Noh SK, Macromol. Rapid Commun.in press
  •  
  • 18. Wang Y, Zhon X, Wang H, Yas X, Huaxue XuebaoChem. Abstr. 115, 1291295s, 49(11), 1107 (1991)
  •  
  • 19. Wang Y, Zhon X, Youji HuaxueChem. Abstr. 117, 171616u, 12(3), 286 (1992)
  •  
  • 20. Ciruelos S, Cuenca T, Gomez-Sal P, Manzanero A, Royo P, Organometallics, 14, 177 (1995)
  •  
  • 21. Lee DH, Noh SK, Huh WSProceedings of International Metallocene Polymers: Metallocene'95, p. 463, 26-27 April, Brussel, Belgium (1995)
  •  
  • 22. Lee DH, Yoon KB, Lee EH, Noh SK, Lee CS, Hoh WS, Macromol. Rapid Commun., 17, 325 (1996)
  •  
  • 23. Graper J, Paolucci G, Fischer RD, J. Org. Chem., 501, 211 (1995)
  •  
  • 24. Reddy KP, Patterson JL, Organometallics, 8, 2107 (1989)
  •  
  • 25. Gormez R, Cuenca T, Royo P, Hovestreydt E, Organometallics, 10, 2516 (1991)
  •  
  • 26. Spaleck W, Antberg M, Dolle V, Klein R, Rohrmann J, Winter A, New J. Chem., 14, 199 (1990)
  •  
  • 27. Herrmann WA, Rohrmann J, Herdweek E, Spaleck W, Winter A, Angew. Chem.-Int. Edit., 28, 1511 (1989)
  •  
  • 28. Davis BR, Bernal I, J. Org. Chem., 30, 75 (1971)
  •  
  • 29. Roll W, Zsolnai L, Huttner G, Brintzinger HH, J. Org. Chem., 322, 65 (1987)
  •  
  • 30. Curtis MD, D'Enricco JJ, Duffy DN, Epstein PS, Bell LG, Organometallics, 2, 1808 (1983)
  •  
  • 31. Mohling PC, Vlachakis N, Coville NE, J. Org. Chem., 483, 159 (1994)
  •  
  • Polymer(Korea) 폴리머
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    ISSN 0379-153X(Print)
    ISSN 2234-8077(Online)
    Abbr. Polym. Korea
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This Article

  • 1997; 21(3): 361-368

    Published online May 25, 1997