簡易檢索 / 詳目顯示
| 研究生： |
林景山 Ching-Shan Lin |
|---|---|
| 論文名稱： |
聚偏二氟乙烯/環己酮凝膠結構形成之研究 A Study of Structural Formation in Poly(vinylidene fluoride)/Cyclohexanone Gels |
| 指導教授： |
洪伯達
Po-Da Hong |
| 口試委員: |
廖文彬
Wen-Bin Liau 黃延吉 Yan-Jyi Huang 陳志堅 Jhih Chien Chen |
| 學位類別： |
碩士 Master |
| 系所名稱： |
工程學院 - 材料科學與工程系 Department of Materials Science and Engineering |
| 論文出版年： | 2006 |
| 畢業學年度： | 94 |
| 語文別： | 中文 |
| 論文頁數： | 53 |
| 中文關鍵詞： | 物理凝膠 、非平衡 、高分子溶液相圖 、小角光散射 |
| 外文關鍵詞： | physical gels, non-equilibrium, polymer solution phase diagram, small angle light scattering |
| 相關次數： | 點閱：210 下載：8 |
| 分享至: |
| 查詢本校圖書館目錄 查詢臺灣博碩士論文知識加值系統 勘誤回報 |
熱可逆物理凝膠主要是由分子鏈間，以物理結合所構成的三次元網狀構造。對於具有結晶化過程的物理凝膠系統中，凝膠化的發生通常與成核成長過程有很大的關係。本論文主要先建立完整的溫度跟組成相圖以及利用小角光散射技術分析高分子溶液不同相區間其成核成長行為。首先，我們利用落球法、DSC熱差分析測定來求得gel-sol轉移曲線，並將凝膠融點分別帶入Flory-Huggins熔點下降式跟van’t Hoff’s Equation來描述完整的液─固轉移曲線。而且我們將隨著溫度變化的相互作用力參數值帶入高分子溶液的混合自由能當中，從自由能隨組成變化曲線發現在實驗相圖內並無相分離發生，明顯指出凝膠結構受結晶化所控制。並且在本論文當中，首次提出sol-gel轉移曲線受到重力影響發生S型轉折曲線。這裡因為PVDF為半結晶性的高分子，並且由上述證明凝膠結構是受到結晶化控制，當sol轉移到gel相勢必受到溶液中結晶的成核密度所影響，只要成核密度不足就無法形成凝膠相。從相圖中可以清楚看到因為高分子體積分率太低時導致成核密度過小，這時因為受到重力的影響使未形成凝膠的結晶沉澱下來，因此導致在sol-gel轉移曲線有一個明顯轉折。
此外在小角光散射分析中，我們固定體積分率於凝膠區域 (polymer volume fraction=0.084) 做不同等溫(25℃~55℃)以及固定凝膠化溫度30℃改變高分子溶液濃度(ψ=0.034~0.09)藉由小角光散射實驗分析結果發現，Hv散射不變量隨時間變化上所得到初期成核的緩和時間。從各不變量的變化上可以發現在ㄧ個時間點上，不變量突然增加的轉折點表徵誘導期初始時間t0。在PVDF/Cyclohexanone高分子溶液內結晶的成長行為中，從固定濃度且變化溫度的結果中發現當溫度T≦30℃時為擴散控制而溫度T>30℃轉變為界面控制成長。另外，從定溫下且變化濃度範圍的結果中發現當ψ=0.09時為擴散控制而ψ≦0.078轉變為界面控制成長。整理上面不同濃度跟溫度區間來看可以發現過冷卻度因素控制了球晶成長動力學上的過程，並且在30℃ψ=0.084、0.09，25℃ψ=0.084中其過冷卻度 表徵相變趨動力增加，為擴散控制且指數為0.5推論為球晶結構其內部枝化的過程中產生緻密的分形型態。而過冷卻度小其指數皆為1表示其微凝膠進行著由界面控制成長主導類似高分子球晶的成長過程。
Thermoreversible physical gel is a three-dimensional network of polymer chains cross-linked by physical association. Basically, the gelation is closely related to nucleation and growth in the physical gel system which contained crystallization behavior. In this study, we establish complete composition-temperature phase diagram and used small angle light scattering to investigate the nucleation and growth in different region. Polyvinylidene fluoride/Cyclohexanone physical polymer gels was investigated through falling ball method、DSC for gel-sol transition curve. By using Flory Huggins melting depression and van’t Hoff’s equation, we build up complete L-S transition curve. And we carry the Flory-Huggins interaction parameter into the mixing of Gibbs free energy equation for polymer solution which obtained the energy of mixing is negative in our experimental phase diagram. The finding is that the polymer solution in our study is a good solvent system. In addition, we first found out the turning of the sol-gel transition curve which is caused by gravity. Combination of the phase diagram and the result in different show that the L-S transition for the unique gelation behavior.
As stated above, the crystallization in polymer solution was study by time-resolved small angle light scattering. We also discuss the relation between invariant on Hv light scattering and current viewpoint on the growth of crystal in polymer solution. The induced period, t0, is found by extrapolation of the linear part of the linear part to intersect the t axis. For the growth of crystals in polymer solution, using the characteristic wave number and time should be rescaled in reduced units with the exponential relationship. The super cooling temperature effected for variant polymer volume fraction and gelation temperature. For diffusion-controlled growth, the radius of the nuclei increases as t1/2(the branching process in spherulite growth has dense fractal morphology). For interface-controlled growth, the radius of nuclei increases linearly with time (the growth of polymer spherulite). However, both interface-controlled growth and diffusion-controlled growth is the kinetic model, which does not involve the structural information of the the growth domains.
1. Flory, P.J., Disc Farad Sco. 1974, 57, 1.
2. Guenet, J., Thermoreversible Gelation of Polymers and Biopolymers; Academical: London, 1992.
3. De Gennes, P. G., Scaling Concepts in Polymer Physics; Cornell University Press: Ithaca, 1985.
4. Stauffer, D.; Coniglio, A.; Adam, M., Adv. Polym. Sci. 1982, 44, 105.
5. Hong, P. D.; Chou, C.M., Polymer 2000, 41, 8311.
6. Hong, P. D.; Chou, C.M., Macromolecules 2000, 33, 9673.
7. Haasen, P., Materials Science and Technology, Vol. 5. “Phase Transformation in Materials”, Weinheim; New York. 1991.
8. Lorén, N.; Altskär, A.; Hermansson, A. M., Macromolecules 2001, 34, 8117.
9. Chou, C.M.; Hong, P. D., Macromolecules 2004, 37, 5596.
10. Binder, K. Phys. Rev. A 1984, 29, 341.
11. Schätzel, K.; Ackerson, B. J. Phys. Rev. Lett. 1992, 68, 337.
12. Olmsted, P. D.; Poon, W. C. K.; Mcleish, T. C. B.; Terrill, N.J.; Ryan, A. J. Phys. Rev. Lett. 1998, 81, 373.
13. Sedgewick, H.; Kroy, K.; Salonen, A.; Robertson, M.B.; Egelhaaf, S.U.; Poon, W. C. K. Eur. Phys. J. E. 2005, 16, 77.
14. Cates, M. E.; Wittmer, J. P.; Bouchaud, J. P.; laudin, P., Physic. Rev. Lett. 1998, 81, 1841.
15. Lui, A. J.; Nagel, S. R., Nature 1998, 396, 21.
16. Trappe, V. ; Prasad, V. ; Cipelletti, L. ; Segre, P. N. ; Wetiz, D. A., Nature 2001, 411, 772.
17. Strafod, K.; Adhikari, R.; Pagonabarrage, I.; Desplat, J. C.; Cates, M. E., Science 2005, 309, 2198.
18. Henkes, S.; Chakraborty, B., Phys. Rev. Lett. 2005, 95, 198002.
19. Drocco, J. A.; Hasting, M. B.; Olson Reichhardt, C. J.; Reichhardt, C., Phys. Rev. Lett. , 2005, 95, 088001.
20. Berne, B.J.; Pecora, R., Dynamic Light scattering; Wiley: New York, 1976.
21. Schätzel, K.; Ackerson, B. J., Phys. Rev. Lett. 1992, 68, 337.
22. Carpineti, M.; Giglio, M., Phys. Rev. Lett. 1992, 68, 3327.
23. Takenaka, M.; Hashimoto, T., J. Chem. Phys. 1992, 96, 6177.
24. Gumming, A.; Wiltzius, P.; Bates, F. S.; Rosedale, J. H., Phys. Rev. A 1992, 45, 885.
25. Takeshita, H.; Kanaya, T.; Nishida, K.; Kaji, K., Macromolecules 1999, 32, 7815.
26. Manno, M.; Palma, M. U., Phys. Rev. Lett. 1997, 91, 3258.
27. Stein, R. S.; Rhodes, M. B., J. Appl. Phys. 1960, 31, 1873.
28. Rhodes, M. B.; Stein, R. S., J. Polym. Sci., Part A-2 1969, 7, 1539.
29. Nishi, T.; Wang, T. T., Macromolecules 1975, 8, 909.
30. Thomas, E.L., Materuals Science and Technology, Vol. 12. “Structure and Properties of polymer”; Weinheim: New York. 1993.
31. Martin, M.; Franz, R., J. Chem. Phys. 1997, 6, 107.
32. Michael L.; Tina M. T.; Marc D., Phys. Rev. Lett.1996, 6, 53.
33. Ohkura, M.; Kanaya T.; Kaji K., Polymer 1992, 33, 3686.
34. Okabe, M.; Wada, R.; Tazaki, M.; Homma, T., Polymer J. 2003, 35, 798.
35. Samuels, R. J. J. Polym. Sci.,Phys.Ed. 1971, 9, 2165.
36. Stein, R. S.; Rhodes, M. B. J. Appl. Phys. 1960, 31, 1873.
37. Meeten, G. H., J. Polym. Sci., Phys.Ed. 1989, 27, 2023.
38. Desbordes, M.; Meeten, G. H.; Navard, P., J. Polym. Sci.,Phys.Ed. 1989, 27, 2027.
39. Ariveu, C.; Navard, P., J. Polym. Sci.,Phys.Ed. 1989, 27, 2157.
40. Peuvrel, E.; Siegert, D.; Navard, P.; Meeten, G. H., J. Polym. Sci.,Phys.Ed. 1992, 30, 865.
41. Meeten, G. H., Optical Properties of Polymers; Elsevier: London, 1986.
42. Papon, P.; Leblond, J.;Meijer, P. H. E., The Physical of phase transitions, Springer; New York, 2002.
43. Lefebvre, A. A.; Lee, J. H.; Balsara, N. P.; Vaidyanathan, C., J. Chem. Phys. 2002, 117, 9063.
44. Balsara, N. P.; Lin, C.; Hammouda, B., Phys. Rev. Lett. 1996, 77, 3847.
45. Lefebvre, A. A.; Lee, J. H.; Balsara, N. P.; Hammouda, B., J. Chem. Phys. 2002, 116, 4777.
46. Imai, M.; Kaji, K.; Kanaya, T., Phys. Rev. Lett. 1993, 71, 4162.
47. Tomura, H.; Saito, H.; Inoue, T., Macromolecules 1992, 25, 1611.
48. Leblond, J.; Meijer, P. H. E., The physical of phase transition, Springer; New York, 2002.
