Article
  • Thermal Behavior of Syndiotactic Polypropylene/Atactic Polypropylene Blends
  • Kim I, Lee SW, Kim YT
  • 신디오탁틱 폴리프로필렌/아탁틱 폴리프로필렌 블렌드의 열적 거동
  • 김일, 이순우, 김영태
Abstract
Syndiotactic polypropylene (sPP) showing high racemic pentad (rrrr) value of 97.6% has been synthesized by iPr-(Cp)(Flu)ZrMe2 (iPr-(Cp)(Flu)= isopropylidene(1-η5-cyclopentadienyl)(1-η5-fluorenyl)) compound which is prepared by the methylation of syndiospecific metallocene catalyst, iPr-(Cp)(Flu)ZrCl2 by using MgMe2, cocatalyzed with noncoordinating anionic compound, [HNMe2Ph][B(C6F 5)4]. Neat sPP has been characterized by 13C NMR, IR, x-ray diffraction, DSC, and TGA analysis. Various sPP/atactic polypropylene (aPP) blends (sPP/aPP= 90/10, 80/20, and 60/40) prepared by solution blending were also analysed by the same methods. According to the IR analysis carried out by polymer films there exists a good correlation between IR index and the enthalpy of melting (ΔHm) of polymer. The x-ray crystallinity of the blend is decreased with the amount of aPP. sPP and its blends show double melting peaks representing polymorphism. The number and the area ratio of each peak are dependent on thermal history of the sample. The results of analysis by Avrami equation shows that the half-time of crystallization is decreased according to the increase of aPP content and that Avrami index is in the range of 2.10 and 3.15. The equilibrium melting temperature of neat sPP is 152.6℃, and those of sPP/aPP blends are 151.5, 150. 8, and 147.5℃ for sPP/aPP = 90/10, 80/20, and 60/40, respectively.

신디오특이성을 가진 isopropylidene (1-η5-cyclopentadienyl) (1-η5-fluorenyl)dichlorozirconium (iPr-(Cp)(Flu)ZrC12)을 MgMe2로 메틸화하여 iPr-(Cp) (Flu)ZrMe2촉매를 합성하고 비배위성 음이온형 화합물인 [HNMe2Ph][B(C6F5 )4]를 공촉매로 하여 racemic pentad (rrrr)가 97.6%인 신디오탁틱 폴리프로필렌 (sPP)을 제조하였다. 얻은 sPP는 13C NMR, IR, x-ray 회절, DSC 및 TGA 등을 사용하여 분석하였다. 또한 sPP를 아탁틱 폴리프로필렌 (aPP)과 여러 가지 비율(sPP/aPP=90//10, 80/20, 60/40)로 블렌드하여 간은 방법으로 분석함으로써 aPP의 첨가에 따른 sPP의 물성 변화를 조사하였다. sPP/aPP 블렌드 필름을 이용한 IR 분석 결과 IR 지수는 고분자의 ΔHm과 선형 관계를 보였고, x-ray 회절 분석으로부터 고분자의 결정화도는 aPP의 첨가에 따라 감소하는 것을 알 수 있었다. sPP와 sPP/aPP 블렌드는 전형적인 다형태성의 용융 피이크를 나타내었다. 용융 피이크의 크기와 수는 용융 피이크의 열이력 (승온속도와 냉각속도 등)에 따라 크게 달라졌다. Avrami 방정식의 해석에 의한 블렌드의 결정화 반감기는 sPP가 첨가됨에 따라 증가하였고, Avrami 지수(n)는 2.10∼3.15로 나타났다. 평형 융점은 sPP가 152.6℃였고, sPP/aPP=90/10, 80/20, 60/40일 때 차례로 151.5, 150.8, 147.5℃로 감소하였다.

Keywords: syndiotactic polypropylene; syndiotactic/atactic polypropylene blends; polymorphism thermal behavior

References
  • 1. Natta G, Pasquon I, Corradini P, Peraldo M, Pegoraro M, Zambelli A, Rend. Acc. Naz. Lincei., 28, 539 (1960)
  •  
  • 2. Natta G, Pasquon I, Zambelli A, J. Am. Chem. Soc., 84, 539 (1960)
  •  
  • 3. Zambelli A, Natta G, Pasquon I, J. Polym. Sci. C: Polym. Lett., 4, 411 (1963)
  •  
  • 4. Boor J, Youngman EA, J. Polym. Sci. A: Polym. Chem., 4, 1861 (1966)
  •  
  • 5. Doi Y, Suzuki S, Soga K, Macromolecules, 19, 2869 (1986)
  •  
  • 6. Natta G, Corradini P, Chim. Ind., 45, 299 (1963)
  •  
  • 7. Corradini P, Nata G, Ganis P, Temussi PA, J. Polym. Sci. C: Polym. Lett., 16, 2477 (1967)
  •  
  • 8. Galambos A, Wotkowicz M, Zeigler R, Galimberti M, Polym. Mat. Sci. Eng., 64, 45 (1991)
  •  
  • 9. Gee DR, Melia TP, Polymer, 10, 239 (1969)
  •  
  • 10. Clark EJ, Hoffman JD, Macromolecules, 17, 878 (1984)
  •  
  • 11. Lotz B, Lovinger AJ, Cais RE, Macromolecules, 21, 2375 (1988)
  •  
  • 12. Lovinger AJ, Lotz B, Davis DD, Polymer, 31, 2253 (1990)
  •  
  • 13. Lovinger AJ, Davis DD, Lotz B, Macromolecules, 24, 552 (1991)
  •  
  • 14. Ewen J, Jones L, Razavi A, J. Am. Chem. Soc., 110, 6255 (1988)
  •  
  • 15. Uehara H, Yamazaki Y, Kanamoto T, Polymer, 37(1), 57 (1996)
  •  
  • 16. De Rosa C, Corradini P, Macromolecules, 26, 5711 (1993)
  •  
  • 17. Kaminsky W, Engehausen R, Zoumis K, Spaleck W, Rohrmann J, Macromol. Chem., 193, 1643 (1992)
  •  
  • 18. Ewen JA, Elder MJ, Jones RL, Haspeslagh L, Atwood JL, Bott SG, Robinson K, Makromol. Chem. Macromol. Symp., 48-49, 253 (1991)
  •  
  • 19. Lee MH, Park JW, Hong CS, Woo SI, Do Y, J. Org. Chem.submitted for publication (1997)
  •  
  • 20. Ashby EC, Williard GF, J. Org. Chem., 43, 4750 (1978)
  •  
  • 21. Kim I, Kim KT, Lee MH, Do Y, Won M, J. Appl. Polym. Sci.submitted for publication (1997)
  •  
  • 22. Boor JZiegler-Natta Catalysis and Polymerizations, p. 47, Academic Press, New York (1979)
  •  
  • 23. Boor J, Youngman EA, J. Polym. Sci. A: Polym. Chem., 4, 1981 (1966)
  •  
  • 24. Boor J, Youngman EA, Polym. Lett., 3, 577 (1965)
  •  
  • 25. Ogawa T, Elias HG, J. Macromol. Sci., A17, 727 (1982)
  •  
  • 26. Marchetti A, Martuscelli E, J. Polym. Sci. B: Polym. Phys., 12, 1649 (1974)
  •  
  • 27. Corradini P, Natta G, Ganis P, Temussi PA, J. Polym. Sci. C: Polym. Lett., 16, 2477 (1967)
  •  
  • 28. Fierro R, Yu ZT, Rausch MD, Dong SZ, Alvares D, Chien JC, J. Polym. Sci. A: Polym. Chem., 32(4), 661 (1994)
  •  
  • 29. Rodriguezarnold J, Zhang AQ, Cheng SZ, Lovinger AJ, Hsieh ET, Chu P, Johnson TW, Honnell KG, Geerts RG, Palackal SJ, Hawley GR, Welch MB, Polymer, 35(9), 1884 (1994)
  •  
  • 30. Avrami MJ, J. Chem. Phys., 7, 1103 (1939)
  •  
  • 31. Avrami MJ, J. Chem. Phys., 8, 202 (1940)
  •  
  • 32. Elias HG, Macromolecules, 1, 373 (1977)
  •  
  • 33. Hoffman JD, Weeks J, Res. Natal. Bur. Stand. Sect. A, 13, 66 (1962)
  •  
  • 34. Haftka S, Konnecke K, J. Macromol. Sci.-Phys., B30(4), 319 (1991)
  •  
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This Article

  • 1998; 22(2): 240-250

    Published online Mar 25, 1998