臺灣博碩士論文加值系統

本論文探討PEG/RAN混合物在空間侷限效應下，表面潤濕效應對失穩分解的相分離行為的影響。首先從曇點所建立的相圖中，我們發現相分離的臨界點並未如理論與模擬的預言般，在表面潤濕的作用下會隨樣品厚度有所偏移。我們推論其來自於相分離系統的臨界點潤濕行為取決於系統中液-液-固三相的形成。因此，只有當相分離後期，兩個相的界面明銳時，潤濕效應才會明顯的發生。的確，我們對近臨界組成的失穩分解行為的形態學與動力學觀察中，發現潤濕效應的發生，有時間上的順序，與先前研究所認為的協同進行有所不同。我們利用顯微影像分析與小角光散射實驗定量探討在空間侷限下的表面潤濕效應對失穩分解的影響大致分為四階段：(1) 典型失穩分解的流體力學粗化成長；(2) 易潤濕PEG-rich相朝石英侷限壁潤濕鋪展；(3) 連接兩潤濕層間通道的成核-成長行為，且通道具臨界尺寸，在小於臨界尺寸的通道將收縮消失；(4) 相鄰通道間的合併與形狀的緩和。更重要的是，隨時間拉長，我們並未觀察到平衡潤濕層的存在，反而發生了相溶解。這個潤濕所驅動的相溶解行為調和了先前熱力學理論與動力學實驗間的不自洽的問題。具體來說，於本體（三維）中穩定的兩液相和薄膜（二維）的情況中只是亞穩的。潤濕作用會使兩相組成重新分配，達到新平衡。因此在空間侷限且存有表面潤濕作用下，真正的平衡是形成表面偏析的單相結構，而非相分離的巨觀兩相。所以相溶解行為發生。另外，又觀察到不同溫度會因表面張力驅使管道形狀緩和的速率不同，有可能作為測量液-液兩相界面張力的依據。

In this work, the surface-wetting effects on spinodal decomposition behavior of the PEG/RAN mixtures under the confinement were investigated using turbidimetry, light scattering and microscope analyses. Firstly, the critical temperature of phase separation evaluated from the cloud point has no change with sample thickness as the same with the prediction from theoretical simulation on the surface-wetting effect. It is well known that wetting effect on the critical point of phase separation depends on the formation of three-phase system (liquid-liquid-solid phase) in general. Hence, the wetting behavior will take place in the late-stage of phase separation in which the system exists the sharp interface between two phases. From the morphological observation and the kinetics of spinodal decomposition for the near-critical composition, however, the occurrence of wetting effect was found in chronological order and this phenomenon is quite different from that reported in other literatures. In this study, the surface-wetting effect on spinodal decomposition in the confined space would be elucidated further with considering the mechanisms of structural evolution for a phase-separating system. In summary, the structural change with time during spinodal decomposition process can be divided into four stages: (1) typical hydrodynamic coarsening of spinodal decomposition; (2) wetting PEG-rich phase spreading on the quartz confined wall; (3) the nucleation-growth behavior of channels connecting to two wetting layer (there exists a critical radius, so the channels will shrink and then disappear if the channel is smaller than the critical radius); (4) the closure and shape relaxation of channels. Most importantly, the existence of equilibrium wetting layers with time was not observed in this work, whereas the phase dissolution occurs. The wetting-driven phase dissolution behavior harmonizes the inconsistency between the thermodynamic theory and kinetic experiments. Strictly speaking, the two-phase separation should be stable in the bulk (3D), while it is considered to be metastable in thin film (2D). The wetting effect will reconstruct the two-phase composition, and then this will reach a new equilibrium state. Therefore, for the surface-wetting effect in confined space, the real equilibrium state may mean that the formation of one-phase structure with surface segregation is rather important than that of two-phase phase separation. Therefore, the phase dissolution has to be expected to occur under these arguments. On the other hand, the shape relaxation rate of channels is found to correlate with the temperature and this fact might be considered due to the change in surface tension. To concern further about the effects of surface tension on the mechanism of liquid-liquid phase separation is very important in the near future.

Abstract II
誌謝 III
目錄 IV
圖表索引 VI
符號表 IX
第 1章 前言 1
1.1. 高分子混合物的失穩分解 1
1.2. 本體相中的相分離熱力學、動力學與形態學 2
1.3. 相分離系統中的空間侷限與表面潤濕現象 6
1.3.1. 空間侷限下的相分離行為 6
1.3.2. 臨界點潤濕 7
1.3.3. 潤濕效應對相分離熱力學的影響 8
1.3.4. 潤濕效應對失穩分解動力學的影響 10
1.4. 研究目的 12
第 2章 實驗部分 13
2.1. 材料 13
2.1.1. PEG純化 13
2.1.2. RAN純化 13
2.1.3. 混合物樣品製備 13
2.2. 實驗儀器與方法 14
2.2.1. 相位差顯微鏡 (PCM) 14
2.2.2. 小角度光散射 (SALS) 14
2.2.3. 快速冷卻系統 15
2.3. 顯微影像分析 16
2.3.1. 影像傅立葉變換 16
2.3.2. 影像的形態學分析 17
第 3章 結果與討論 19
3.1. PEG/RAN 混合物的本體相圖 19
3.2. 潤濕效應對PEG/RAN混合物相分離的影響 20
3.3. 空間侷限效應對PEG/RAN混合物相分離的影響 21
3.4. 表面潤濕效應下的失穩分解行為 23
3.5. 失穩分解之後潤濕層間通道的形成與成長 26
3.5.1. 通道的初期成長階段 28
3.5.2. 通道的後期演化階段 31
3.6. 表面潤濕效應下的失穩分解動力學 32
3.7. 潤濕通道演化的形態學分析 35
第 4章 結論 37
參考文獻 38

1.Siggia, E. D. “Late stages of spinodal decomposition in binary mixtures.” Phys. Rev. A 1979, 20, 595-605.
2.Annabi, N.; Nichol, J. W., Zhong, X.; Ji, C.; Koshy, S.; Khademhosseini, A.; Dehghani, F. “Controlling the porosity and microarchitecture of hydrogels for tissue engineering.” Tissue Engineering Part B: Reviews, 2010, 16, 371-383.
3.Chou, C.-M.; Hong, P.-D. “Scattering Modeling of Nucleation Gels.” Macromolecules 2008, 41, 6540–6545.
4.Chou, C.-M.; Hong, P.-D. “Spatiotemporal Evolution in Morphogenesis of Thermoreversible Polymer Gels with Fibrillar Network.” Macromolecules 2010, 43, 10621–10627.
5.Chou, C.-M.; Hong, P.-D. “Morphogenetic Transition in Weak Gelation of Crystallizable Linear Polymers.” ACS Macro Lett. 2012, 1, 646–650.
6.Sánchez-Díaz, L. E.; Vizcarra-Rendón, A.; Juárez-Maldonado, R. “Ionic and wigner glasses, superionic conductors, and spinodal electrostatic gels: dynamically arrested phases of the primitive model.” Phys. Rev. Lett. 2009, 103, 035701.
7.Cahn, J. W.; Hilliard, J. E. “Free energy of a nonuniform system. I. Interfacial free energy.” J. Chem. Phys. 1958, 28, 258-267.
8.Cahn, J. W.; Hilliard, J. E. “Free Energy of a Nonuniform System. III. Nucleation in a Two‐Component Incompressible Fluid.” J. Chem. Phys. 1959, 31, 688-699.
9.Lifshitz, I. M.; Slyozov, V. V. The kinetics of precipitation from supersaturated solid solutions. J. Phys. Chem. Sloids 1961, 19, 35-50.
10.Binder, K.; Stauffer, D. “Statistical theory of nucleation, condensation and coagulation.” Adv. Phys. 1976, 25, 343-396.
11.Hashimoto, T.; Itakura, M.; Hasegawa, H. “Late stage spinodal decomposition of a binary polymer mixture. I. Critical test of dynamical scaling on scattering function.” J. Chem. Phys. 1986, 85, 618-6128.
12.Hashimoto, T.; Itakura, M.; Shimidzu, N. “Late stage spinodal decomposition of a binary polymer mixture. II. Scaling analyses on Qm (τ) and Im (τ).” J. Chem. Phys. 1986, 85, 6773-6786.
13.Kyu, T.; Saldanha, J. M. “Phase separation by spinodal decomposition in polycarbonate/poly (methyl methacrylate) blends.” Macromolecules 1988, 21, 1021-1026.
14.Kedrowski, C.; Bates, F.S.; Wiltzius, P. “Dynamic scaling in spinodally decomposing isotopic polymer mixtures.” Macromolecules 1993, 26, 3448-3454.
15.Bates, F. S.; Wiltzius, P. “Spinodal decomposition of a symmetric critical mixture of deuterated and protonated polymer.” J. Chem. Phys. 1989, 91, 3258-3274.
16.Furukawa, H. “A dynamic scaling assumption for phase separation.” Adv. Phys. 1985, 34, 703-750
17.Takenaka, M.; Izumitani, T.; Hashimoto, T. “Slow spinodal decomposition in binary liquid mixtures of polymers. IV. Scaled structure factor for later stage unmixing.” Chem. Phys. 1990, 92, 4566-4575.
18.Koga, T; Kawasaki, K. “Late stage dynamics of spinodal decomposition in binary fluid mixtures.” Physical A 1993, 196, 389-415.
19.Shinozaki, A.; Oono, Y. “Spinodal decomposition in 3-space.” Phys. Rev. E 1993, 48, 2622.
20.Shinozaki, A.; Oono, Y. “Asymptotic form factor for spinodal decomposition in three-space.” Phys. Rev. Lett. 1991, 66, 173.
21.Tanaka, H. “Universality of viscoelastic phase separation in dynamically asymmetric fluid mixtures.” Phys. Rev. Lett. 1996, 76, 787.
22.Tanaka, H. “Viscoelastic phase separation.” J. Phys.: Condens. Matter 2000, 12, R207.
23.Tanaka, H. “Formation of network and cellular structures by viscoelastic phase separation.” Adv. Mater. 2009, 21, 1872-1880.
24.Tanaka, H. “Viscoelastic phase separation in soft matter and foods.” Faraday Discuss. 2012, 158, 371-406.
25.Tanaka, H. “New coarsening mechanisms for spinodal decomposition having droplet pattern in binary fluid mixture: Collision-induced collisions.” Phys. Rev. Lett. 1994, 72, 1702.
26.Tanaka, H. “A new coarsening mechanism of droplet spinodal decomposition.” J. Chem. Phys. 1995, 103, 2361-2364.
27.Tanaka, H. “Coarsening mechanisms of droplet spinodal decomposition in binary fluid mixtures.” J. Chem. Phys. 1996, 105, 10099-10114.
28.Nikolayev, V. S.; Beysens, D.; Guenoun, P. “New hydrodynamic mechanism for drop coarsening.” Phys. Rev. Lett. 1996, 76, 3144−3147.
29.Jones, R. A. L.; Norton, L. J.; Kramer, J.; Bates, F. S.; Wiltzius, P. “Surface-directed spinodal decomposition.” Phys. Rev. Lett. 1991, 66, 1326−1329.
30.Puri, S. “Surface-directed spinodal decomposition.” J. Phys.: Condens. Matter 2005, 17, R101.
31.Flory, P. J. Principles of Polymer Chemistry; Cornell University Press: New York, 1953.
32.Hashimoto, T. In Structure and Properties of Polymers; Thomas, E. L., Ed.; Wiley-VCH: New York, 1993; Chapter 6.
33.Lifshitz, I. M.; Slyozov, V. V. J. “The kinetics of precipitation from supersaturated solid solutions.” Phys. Chem. Solids 1961, 19, 35−50.
34.Stanley, H. E. Introduction to Phase Transitions and Critical Phenomena; Oxford University Press: New York, 1971.
35.Nose, T. “Coexistence curves of polystyrene/poly (dimethylsiloxane) blends.” Polymer 1995, 36, 2243−2248.
36.Stepanek, P.; T. Lodge, P.; Kedrowski, C.; Bates, F. S., “Critical Dynamics of Polymer Blends.” J. Chem. Phys. 1991, 94, 8289-8301.
37.Jayalakshmi, Y.; Khalil, B.; Beysens, D. “Phase separation under a weak concentration gradient.” Phys. Rev. Lett. 1992, 69, 3088.
38.Perrot, F.; Guenoun, P.; Baumberger, T.; Beysens, D.; Garrabos, Y.; Le Neindre, B. “Nucleation and growth of tightly packed droplets in fluids.” Phys. Rev. Lett. 1994, 73, 688.
39.Hayward, S.; Heermann, D. W.; Binder, K. “Dynamic percolation transition induced by phase separation: A Monte Carlo analysis.” J. Stat. Phys. 1987, 49, 1053-1081.
40.Aharony, A.; Stauffer, D. Introduction to percolation theory. Taylor & Francis, 2003.
41.Hsu, D. Y.; Chou, C. M.; Chuang, C. Y.; Hong, P. D. “Percolation of Phase-Separating Polymer Mixtures.” ACS Macro Lett. 2015, 4, 1341-1345.
42.De Gennes, P. G.; Brochard-Wyart, F.; Quéré, D. Capillarity and Wetting Phenomena. Springer, New York, 2004.
43.Hashimoto, T.; Jinnai, H.; Nishikawa, Y.; Koga, T.; Takenaka, M . “Sponge-like structures and their Gaussian curvatures in polymer mixtures and microemulsions.” Progr. Colloid. Polym. Sci. 1997, 106, 118-126
44.Koga, T.; Jinnai, H.; Hashimoto, T. “Interfacial curvature in phase-separating binary fluids: comparison between computer simulation and experiments.” Physica A 1999, 263, 369-377.
45.Nakanishi, H.; Fisher, M. E. “Critical point shifts in films.” J. Chem. Phys. 1983, 78, 3279−3293.
46.Tang, H.; Szleifer, I.; Kumar, S. K. “Critical temperature shifts in thin polymer blend films.” J. Chem. Phys. 1994, 100, 5367−5371.
47.Bonn, D.; Ross, D. “Wetting transitions.” Rep. Prog. Phys. 2001, 64, 1085−1163
48.Cahn, J. W. “Critical point wetting.” J. Chem. Phys. 1977, 66, 3667−3672.
49.Fisk, S.; Widom, B. “Structure and free energy of the interface between fluid phases in equilibrium near the critical point.” J. Chem. Phys. 1969, 50, 3219-3227.
50.Indekeu, J. O. “How universal is critical-point wetting?.” Physica A 1991, 177, 428-436.
51.Binder, K.; Das, S. K.; Horbach, J.; Puri, S. “Molecular dynamics simulations of surface-controlled phase separation of binary fluid mixtures confined in slit pores.” Eur. Phys. J. 2007, 141, s1-s6.
52.Jaiswal, P. K.; Binder, K.; Puri, S. “Formation of metastable structures by phase separation triggered by initial composition gradients in thin films.” J. Chem. Phys. 2012, 137, 064704.
53.Flebbe, T., Dünweg, B.; Binder, K. “Phase separation versus wetting: a mean field theory for symmetrical polymer mixtures confined between selectively attractive walls.” J. Phys. II 1996, 6, 667-695.
54.Müller, M.; Binder, K.; Albano, E. V. “Finite size effects on the phase diagram of a binary mixture confined between competing walls.” Physica A 2000, 279, 188-194.
55.Binder, K.; Müller, M.; Albano, E. V. “Symmetric binary polymer blends confined in thin films between competing walls: Interplay between finite size and wetting behavior.” Phys. Chem. Chem. Phys. 2001, 3, 1160-1168.
56.Wiltzius, P.; Cumming, A. “Domain growth and wetting in polymer mixtures.” Phys. Rev. Lett. 1991, 66, 3000.
57.Shi, B. Q.; Harrison, C.; Cumming, A. “Fast-mode kinetics in surface-mediated phase-separating fluids.” Phys. Rev. Lett. 1993, 70, 206.
58.Harrison, C.; Rippard, W.; Cumming, A. “Video microscope and elastic light scattering studies of fast-mode kinetics in surface-mediated spinodal decomposition.” Phys. Rev. E 1995, 52, 723.
59.Tanaka, H. “Simple Hydrodynamic Model of Fast-Mode Kinetics in Surface-Mediated Fluid Phase Separation.” Phys. Rev. E 1996, 54, 1709–1714.
60.Bastea, S.; Puri, S.; Lebowitz, J. L. “Surface-directed spinodal decomposition in binary fluid mixtures.” Phys. Rev. E 2001, 63, 041513.
61.Puri, S.; Jaiswal, P. K.; Das, S. K.; Nehru, J.; Mainz, “Surface-Directed Spinodal Decomposition and Enrichment in Fluid Mixtures: Molecular Dynamics Simulations — Kinetics of Fluid Mixtures at Surfaces.” Eur. Phys. J. 2013, 222 , 961–974.
62.Das, S. K.; Puri, S.; Horbach, J.; Binder, K. “Spinodal decomposition in thin films: Molecular-dynamics simulations of a binary Lennard-Jones fluid mixture.” Phys. Rev. E 2006, 73, 031604.
63.Eliçabe, G. E. “Light scattering of phase separated systems by nucleation‐growth mechanisms: a model based on the Fast Fourier Transform.” Macromolecular theory and simulations 1999, 8, 375-381.
64.Nixon, M. S.; Aguado, A. S. Feature extraction & image processing for computer vision. , 3rd ed.; Elsevier Science: Oxford, 2012.
65.Gonzalez, R. C.; Woods, R. E.; Eddins, S. L. Digital image processing using MATLAB, 2nd ed.; Gatesmark Publishing: United States, 2009
66.莊青諺,空間局限與潤濕效應對聚乙二醇/聚 (乙二醇-丙二醇) 共聚物混合物相分離行為之影響, 2014.
67.Binder, Kurt, et al. Polymers in confined environments. Ed. Steve Granick. Vol. 138. Springer, 2003.
68.Tanaka, H. “Hydrodynamic interface quench effects on spinodal decomposition for symmetric binary fluid mixtures.” Phys. Rev. E 1995, 51, 1313.
69.Bodensohn, J.; Goldburg, W. I. “Spinodal decomposition between closely spaced plates.” Phys. Rev. A 1992, 46, 5084.
70.Tanaka, H. “Wetting dynamics in a confined symmetric binary mixture undergoing phase separation.” Phys. Rev. Lett. 1993, 70, 2770.
71.Jamie, E. A. G.; Dullens, R. P. A.; Aarts, D. G. A. L. “Spinodal decomposition of a confined colloid-polymer system.” J. Chem. Phys. 2012, 137, 204902.
72.Datt, C.; Thampi, S. P.; Govindarajan, R. “Morphological evolution of domains in spinodal decomposition.” Phys. Rev. E 2015, 91, 010101.
73.Son, Y.; Migler, K. B. “Interfacial tension measurement between immiscible polymers: improved deformed drop retraction method.” Polymer 2002, 43, 3001-3006.
74.Yamane, H.; Takahashi, M.; Hayashi, R.; Okamoto, K.; Kashihara, H.; Masuda, T. “Observation of deformation and recovery of poly (isobutylene) droplet in a poly (isobutylene)/poly (dimethyl siloxane) blend after application of step shear strain.” Journal of Rheology 1998, 42, 567-580.