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博碩士論文 etd-0720104-233819 詳細資訊
Title page for etd-0720104-233819
論文名稱
Title
對排聚苯乙烯之結晶行為
Crystallization Behavior of Syndiotactic Polystyrenes
系所名稱
Department
畢業學年期
Year, semester
語文別
Language
學位類別
Degree
頁數
Number of pages
102
研究生
Author
指導教授
Advisor
召集委員
Convenor
口試委員
Advisory Committee
口試日期
Date of Exam
2004-06-01
繳交日期
Date of Submission
2004-07-20
關鍵字
Keywords
對排聚苯乙烯、球晶、多晶態、平衡熔點、對排聚苯乙烯接枝亂排聚苯乙烯共聚物、對甲基苯乙烯之雜式共聚體、結晶
Equilibrium melting temperature, Syndiotactic polystyrene, Polymorphism, Spherulites, sPS-grafted-aPS, sPS-co-pMS, Crystallization
統計
Statistics
本論文已被瀏覽 5737 次,被下載 1894
The thesis/dissertation has been browsed 5737 times, has been downloaded 1894 times.
中文摘要
本研究先以整合配位聚合技術,採用典型之Cp*Ti(OBu)3觸媒,合成高立體規則度的對排聚苯乙烯或其與對甲基苯乙烯之雜式共聚體;其後再以BuLi脫去一個甲基氫並藉以引發苯乙烯之活性陰離子聚合反應,進而得到不同雜排聚苯乙烯側鏈長度與接枝率之對排聚苯乙烯(sPS-g-aPS)。我們以微差掃描卡計、偏光顯微鏡、掃描式電子顯微鏡、穿透式電子顯微鏡、寬角X光繞射、與小角X光散射等技術仔細分析其結晶行為,得到下列幾個結論: (1) 就對排聚苯乙烯單聚體而言,屬於三角晶系之?相實為高溫穩定晶相(其平衡熔點約為300 oC),屬於正交晶系之?相則為低溫穩定晶相(其平衡熔點約為288 oC)。由於晶面能與結晶熱之差異,?相之熔點受晶板厚度之影響較大;在晶板厚度小於5 nm時,此二相之相對穩定度反轉,造成先前文獻中以?相為高溫相之誤解。 (2) 此二相之晶板皆具高度剛性,不易分支與扭轉,導致球晶在數十微米大小仍未完成球狀對稱形態。先前文獻中所報告之特殊負光性球晶,實為尚未完全發展之鞘形(sheath-like)先驅體在軸向觀察時之誤判,其球晶結構並無特殊之處。 (3) 對甲基苯乙烯之雜式共聚或雜排聚苯乙烯側鏈之接枝皆傾向於壓抑?相之生成,並造成?相之熔點(與平衡熔點)之大幅下降以及軸晶成長速率之明確減緩。
Abstract
Reported is a study of the crystallization behavior of syndiotactic polystyrene (sPS) and its copolymers (with 4-bromostyrene as the comonomer or with atactic polystyrene arms grafted on the comonomer sites) via three sets of experiments. The first involves the study of structural identification of negatively birefringent spherulites by means of polarized light microscopy (PLM) and scanning electron microscopy (SEM). Results indicated that the optically positive and optically negative spherulites have same morphological features. Differences in the optical texture are due entirely to differences in orientation of the (anisotropic) sheaf-like precursors: the rigid nature of crystalline lamellae renders incomplete development of spherical symmetry even at the axialitic size of tens of microns.
In the second part, we propose a modified approach for more precise determination of the Tm* value by taking advantage of the dual-mode distribution of crystalline lamellae in analyzing small-angle X-ray scattering (SAXS) profiles. This method should be generally applicable to other semi-crystalline polymers with dual-mode distribution in lamellar thickness. Results from wide-angle X-ray diffraction (XRD) suggest the presence of ?'-to-?" phase transformation at ca. 264 oC; no indications for the previously proposed ?-to-? transformation are identified. We therefore conclude that the ?' form is truly metastable; the ?"-form is the entropically favored high temperature phase (with Tm* = 300 oC) whereas the more ordered ?' phase (with Tm* = 288 oC) is enthalpically favored at lower temperatures.
In the third set of experiments, identification of effects of copolymerization has been studied via a combination of PLM, differential scanning calorimetry (DSC), XRD, SAXS, and transmission electron microscopy (TEM). Results show that the equilibrium melting temperatures (determined via either Hoffman–Weeks or Gibbs–Thomson plots) of the copolymers are significantly lower than that of the corresponding sPS homopolymer. The PLM observations indicate that the axialitic growth rates in copolymers are drastically lower than that of the corresponding homopolymer at comparable backbone length and supercooling. Both XRD and TEM results indicate preferred formation of the ?" phase upon melt crystallization in the bulk state; however, the ?" phase (instead of ?' phase that is the more commonly observed for sPS homopolymers in the bulk state) is dominant in thin films.
目次 Table of Contents
摘要 I
Abstract II
Table of Contents IV
List of Tables VI
List of Figures VII
1. Background 1
1.1. Introduction 1
1.1.1. Polymorphism in syndiotactic polystyrene 1
1.1.2. Crystal structure of the ? phase 2
1.1.3. Crystal structure of the ? phase 4
1.1.4. The birefringent characters of syndiotactic polystyrene spherulites 6
1.1.5. Equilibrium melting temperature of syndiotactic polystyrene 8
1.1.6. Phase transition of syndiotactic polystyrene 15
1.1.7. Effects of copolymerization 17
1.2. Unresolved Issues 19
1.2.1. Optical birefringence 19
1.2.2. Equilibrium melting temperature 19
1.2.3. The ?-to-? transformation 20
1.2.4. Effects of copolymerization 21
1.3. Objectives and Approaches 23
1.3.1. Structural identification of negatively birefringent spherulites 23
1.3.2. Confirmed equilibrium melting temperature 24
1.3.3. The ?-to-? phase transformation 24
1.3.4. Effects of copolymerization 25
2. Experimental Details 26
2.1. Materials 26
2.2. Instruments 27
2.3. Sample Preparation 28
2.4. Experimental methods 29
2.4.1. Optically negative and positive spherulites 29
2.4.2. Equilibrium melting temperature 29
2.4.3. Confirmation ? to ? phase transformation via HT-XRD 30
2.4.4. Quenched experiment via DSC 30
2.4.5. Spherulitic growth rate measurements via PLM 30
3. Morphology and isothermal crystallization kinetics of sPS 31
3.1. Spherulitic structure - PLM and SEM results 31
3.2. Equilibrium melting temperature determined via DSC 39
3.3. Equilibrium melting temperature determined via small-angle x-ray scattering 46
3.4. Crystallization and melting of ? and ? phases in bulk syndiotactic polystyrene as monitored in situ via high-temperature wide-angle X-ray diffraction 58
3.5. The phase transformation 64
4. Effects of copolymerization 70
4.1. Graft-density of sPS-g-aPS copolymers 70
4.2. The thermogravimertic analysis 72
4.3. Quenched experimental result 73
4.4. Isothermal crystallization kinetics and melting behavior 77
4.5. Phase competition: XRD and TEM observations 85
4.6. Axialites growth rate 90
4.7. Morphology of copolymers 91
4.8. Summary 96
5. Conclusion 97
6. Future Research 99
7. References 100
參考文獻 References
1. Ishihara, N.; Seimiya, T.; Kuramoto, M.; Uoi, M. Macromolecules 1986, 19, 2465.
2. Guerra, G.; Vitagliano, V. M.; De Rosa, C.; Petraccone, V.; Corradini, P. Macromolecules 1990, 23, 1539.
3. Guerra, G.; De Rosa, C.; Vitagliano, V. M.; Petraccone, V.; Corradini, P. J. Polym. Sci. Part B: Polym. Phys. 1991, 29, 265.
4. De Rosa, C.; Guerra, G.; Petraccone, V.; Corradini, P. Polym. J. 1991, 23, 1435.
5. De Rosa, C.; Rapacciuolo, M.; Guerra, G.; Petraccone, V.; Corradini, P. Polymer 1992, 33, 1423.
6. Sun, Y. S.; Woo, E. M. Macromolecules 1999, 32, 7836.
7. Ho, R. M.; Lin, C. P.; Hseih, P. Y.; Chung, T. M.; Tsai, H. Y. Macromolecules 2000, 33, 6517.
8. Evans, A. M.; Kellar, E. J. C.; Knowles, J.; Galiotis, C.; Carriere, C. J.; Andrews, E. H. Polym. Eng. Sci. 1997, 37, 153.
9. Greis, O.; Xu, J.; Asano, T.; Petermann, J. Polymer 1989, 30, 590.
10. De Rosa, C. Macromolecules 1996, 29, 8460.
11. Cartier, L.; Okihara, T.; Lotzs, B. Macromolecules 1998, 31, 3303.
12. Chatani, Y.; Fujii, Y.; Shimane, Y.; Ijitsu, T. Polym. Prepr. ,Jpn. 1988, 37, 1179.
13. Tosaka, M.; Hamada, N.; Tsuji, M.; Kohjiya, S.; Ogawa, T.; Isoda, S.; Kobayashi, T. Macromolecules 1997, 30, 4132.
14. Hamada, N.; Tosaka, M.; Tsuji, M.; Kohjiya, S.; Katayama, K. Macromolecules 1997, 30, 6888.
15. Tosaka, M.; Hamada, N.; Tsuji, M.; Kohjiya, S. Macromolecules 1997, 30, 6592.
16. Tosaka, M.; Tsuji, M.; Kohjiya, S.; Cartier, L.; Lotz, B. Macromolecules 1999, 32, 4905.
17. Wang, C.; Chen, C. C.; Cheng, Y. W.; Liao, W. P.; Wang, M. L. Polymer 2002, 43, 5271.
18. Hoffman, J. D.; Weeks, J. J. J. Res. Natl. Bur. Stand. (U.S.) 1962, A66, 13.
19. Wunderlich, B. Macromolecular Physics; Academic Press: New York, 1980; Vol. 3, Ch. 8.
20. Arnauts, J.; Berghmans, H. Polym. Commun. 1990, 31, 343.
21. Cimmino, S.; Di Pace, E.; Martuscelli, E.; Silvestre, C. Polymer 1991, 32, 1080.
22. Woo, E. M.; Sun, Y. S.; Yang, C. P. Prog. Polym. Sci. 2001, 26, 945.
23. Yang, H.; Hsiao, B. Polym. Mater. Sci. Eng. 1999, 81, 285.
24. Lin, R. H.; Woo, E. M. Polymer 2000, 41, 121.
25. Wang, C.; Hsu, Y. C.; Lo, C.F. J. Polymer 2001, 42, 8447.
26. Wang, C.; Cheng, Y. W.; Hsu, Y. C.; Lin, T. L. J. Polym. Sci., Polym. Phys. 2002, 40, 1626.
27. Marand, H.; Xu, J.; Srinivas, S. Macromolecules 1998, 31, 8219 and references cited therein.
28. Ewen J. C. Kellar; Costas Galiotis; Edgar H. Andrews Macromolecules 1996, 29, 3515.
29. Ho, R. M.; Lin, C. P.; Hseih, P. Y.; Chung, T. M.; Tsai, H. Y. Macromolecules 2001, 34, 6727.
30. Keller, A.; Cheng. S. Z. D. Polymer 1998, 391, 4461.
31. De Rosa, C.; Ruiz de Ballesteros, O.; Di Gennaro, M.; Auriemma, F. Polymer 2003, 44, 1861.
32. Mansfield, M. L. Macromolecules 1987, 20, 1384.
33. Senoo, K.; Endo, K. Tosaka, M.; Murakami, S.; Kohjiya, S. Macromolecules 2001, 34, 1267.
34. T. Liu; K. Ma; Z. Liu; C. He; T.-S. Chung J. Am. Chem. Soc. 2002, 86, 422.
35. Al-Hussein, M.; Strobl, G. Macromolecules 2002, 35, 1672.
36. P. J. Flory J. Chem. Phys. 1942, 10, 51.
37. M. L. Huggins; Ann. N. Y. Acad. Sci. 1942, 42, 1.
38. M. L. Huggins J. Chem. Phys. 1942, 46, 151.
39. M. L. Huggins J. Am. Chem. Soc. 1942, 64, 1712.
40. P. J. Flory, In Principles of Polymer Chemistry, Cornell University Press, Ithaca NY, 1953.
41. Fried, J. R.; Lorez, T.; Ramdas, A. Polym. Eng. Sci. 1985, 25, 1048.
42. Chen, Y. P.; Tsai, J. C.; Hong, J. L. J. Chin. Chem. Soc. 2003, 50, 205.
43. Koberstein, J. T,; Morra, B.; Stein, R. S. J. Appl. Crystallogr. 1980, 13, 34.
44. Debye, D.; Bueche, A. M. J. Appl. Phys. 1949, 20, 518.
45. Roe, R. J. Methods of X-ray and Neutron Scattering in Polymer Science; Oxford University Press: New York, 2000; Ch. 1.
46. Strobl, G. The Physics of Polymers; Springer, 1996; Ch. 4.
47. Simha, R.; Boyer, R. F. J. Chem. Phys. 1962, 37, 1003.
48. Boyer, R. F. Macromol. Sci. 1973, B7, 487.
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