近年來，空間侷限環境對聚合物的相轉變行為已經成為廣泛關注的話題。本研究主要探討聚(3-己基噻吩)(P3HT)在陽極氧化鋁模板(AAO)奈米侷限環境下的結晶方向性。P3HT是一種半導體結晶的聚合物也是有機共軛高分子，其良好的結晶性與光電性質，加上本身的自組裝特性，能夠形成規則的奈米結構，目前廣泛運用於共軛高分子太陽能電池(CPSC)及有機場效電晶體(OFETS)等光學元件中。P3HT的光電特性深受其結晶度與巨觀結晶排列規則度影響，因此，控制這兩個參數對材料的光物理性質極為重要。
在本研究中，藉由國家同步輻射中心的光束線17A-廣角度X光散射(WAXS)來分析P3HT滲透入AAO奈米孔洞後的散射圖譜，利用特徵散射峰和型態分析上的資訊，探討晶體之結晶方向性受結晶溫度的影響，藉由掃描式電子顯微鏡(SEM)觀測P3HT在AAO模板中的晶體結構。由SEM的結果可以發現，利用不同配置樣品的方法與不同結晶條件，P3HT晶體在AAO奈米孔洞中皆為奈米柱的型態而不是奈米管。由WAXS的結果發現，P3HT之結晶方向性在不同結晶條件下，P3HT晶體大多傾向垂直方向結晶(edge-on orientation type)。然而，也可以在一定的結晶條件下促使小部分的P3HT晶體呈現水平方向(face-on orientation type)結晶。由DSC圖譜可以觀察到，相較於P3HT薄膜，在侷限環境下，P3HT的熔點與結晶溫度皆會有明顯的下降；且在較大的侷限環境，會使P3HT的熔點與結晶溫度下降的幅度有顯著的提升。

The effect of spatial confinement on the structure and phase transition behavior of polymer has been a subject of extensive interest. This study is centered on resolving the preferred orientation of poly(3-hexylthiophene) (P3HT) crystallites formed within the 2D nanoconfined space of Anodic Aluminum Oxide Template (AAO) nanochannels. P3HT is a crystalline semiconduting polymer which has attracted significant attention due to its potential in the application as the active material for bulk heterojunction solar cell and organic field-effect transistors (OFETS). The opto-electronic properties of P3HT are expected to strongly depend on its degree of crystallinity and the gobal arrangement of the crystallites; therefore, controlling these two morphological paraemeters is important for tailoring the photophysical properties of the material. In this work, we incorporated P3HT into AAO nanochannels with the diameter of 20 and 100 nm and examined the crystal orientation within the channels as a function of the post treatment condition Tc by means of 2D wide angle X-ray diffraction patterns collected at BL01C2 and BL17A1 at the National Synchrotron Radiation Research Center (NSRRC). The P3HT crystallites predominantly adopted the edge-on orientation with the crystalline backbone aligning perpendicularly to the long axis of the cylindrical pores since this type of orientation was kinetically favored for the long range crystal growth along the channel axis. However, using AAO nanochannels with smaller diameter and an annealing or recrystallization treatment at 160˚C induced the formation of a small fraction of the face-on orientation. It was also found that the as-cast P3HT in the confined space with smaller pore size exhibited higher degree of crystallinity and better orientation. The samples prepared from the xylene solution generally possessed better orientation and higher crystallinity than those prepared from the THF solution. However, we found that melt recrystallization removed the nucleus in the samples, which hindered the crystal growth, resulting in a decrease in the degree of crystallinity.

Chapter 4 References
1. Pan, M., et al., Composite Poly(vinylidene fluoride)/Polystyrene Latex Particles for Confined Crystallization in 180 nm Nanospheres via Emulsifier-Free Batch Seeded Emulsion Polymerization. Macromolecules, 2014. 47(8): p. 2632-2644.
2. Lin, M.-C., B. Nandan, and H.-L. Chen, Mediating polymer crystal orientation using nanotemplates from block copolymer microdomains and anodic aluminium oxide nanochannels. Soft Matter, 2012. 8(28): p. 7306-7322.
3. Wang, H., et al., Confined Crystallization of Polyethylene Oxide in Nanolayer Assemblies. Science, 2009. 323(5915): p. 757-760.
4. Wang, H., et al., Confined Crystallization of PEO in Nanolayered Films Impacting Structure and Oxygen Permeability. Macromolecules, 2009. 42(18): p. 7055-7066.
5. Blaszczyk-Lezak, I., M. Hernández, and C. Mijangos, One Dimensional PMMA Nanofibers from AAO Templates. Evidence of Confinement Effects by Dielectric and Raman Analysis. Macromolecules, 2013. 46(12): p. 4995-5002.
6. Sun, L., et al., Comparison of crystallization kinetics in various nanoconfined geometries. Polymer, 2004. 45(9): p. 2931-2939.
7. Beaudoin, E., et al., Effect of Interfaces on the Melting of PEO Confined in Triblock PS-b-PEO-b-PS Copolymers. Langmuir, 2013. 29(34): p. 10874-10880.
8. Shin, K., et al., Crystalline Structures, Melting, and Crystallization of Linear Polyethylene in Cylindrical Nanopores. Macromolecules, 2007. 40(18): p. 6617-6623.
9. García-Gutiérrez, M.-C., et al., Confinement-Induced One-Dimensional Ferroelectric Polymer Arrays. Nano Letters, 2010. 10(4): p. 1472-1476.
10. Maiz, J., J. Martin, and C. Mijangos, Confinement Effects on the Crystallization of Poly(ethylene oxide) Nanotubes. Langmuir, 2012. 28(33): p. 12296-12303.
11. Hou, P., H. Fan, and Z. Jin, Spiral and Mesoporous Block Polymer Nanofibers Generated in Confined Nanochannels. Macromolecules, 2015. 48(1): p. 272-278.
12. Luo, Y., et al., Dynamic Interactions between Poly(3-hexylthiophene) and Single-Walled Carbon Nanotubes in Marginal Solvent. The Journal of Physical Chemistry B, 2014. 118(22): p. 6038-6046.
13. Martin, C.R., Nanomaterials--a membrane-based synthetic approach. 1994, DTIC Document.
14. Martin, C.R., Template Synthesis of Electronically Conductive Polymer Nanostructures. Accounts of Chemical Research, 1995. 28(2): p. 61-68.
15. Grimm, S., et al., Nondestructive Replication of Self-Ordered Nanoporous Alumina Membranes via Cross-Linked Polyacrylate Nanofiber Arrays. Nano Letters, 2008. 8(7): p. 1954-1959.
16. Grimm, S., et al., Nondestructive Mechanical Release of Ordered Polymer Microfiber Arrays from Porous Templates. Small, 2007. 3(6): p. 993-1000.
17. Furneaux, R.C., W.R. Rigby, and A.P. Davidson, The formation of controlled-porosity membranes from anodically oxidized aluminium. Nature, 1989. 337(6203): p. 147-149.
18. Goh, C., K.M. Coakley, and M.D. McGehee, Nanostructuring Titania by Embossing with Polymer Molds Made from Anodic Alumina Templates. Nano Letters, 2005. 5(8): p. 1545-1549.
19. Baek, S., et al., A facile method to prepare regioregular poly (3-hexylthiophene) nanorod arrays using anodic aluminium oxide templates and capillary force. New Journal of Chemistry, 2009. 33(5): p. 986-990.
20. Foss, C.A., M.J. Tierney, and C.R. Martin, Template synthesis of infrared-transparent metal microcylinders: comparison of optical properties with the predictions of effective medium theory. The Journal of Physical Chemistry, 1992. 96(22): p. 9001-9007.
21. Martin, C.R., Membrane-Based Synthesis of Nanomaterials. Chemistry of Materials, 1996. 8(8): p. 1739-1746.
22. Choi, M.K., et al., Simple Fabrication of Asymmetric High-Aspect-Ratio Polymer Nanopillars by Reusable AAO Templates. Langmuir, 2011. 27(6): p. 2132-2137.
23. Kim, D., et al., Replication of high-aspect-ratio nanopillar array for biomimetic gecko foot-hair prototype by UV nano embossing with anodic aluminum oxide mold. Microsystem Technologies, 2007. 13(5-6): p. 601-606.
24. Blaszczyk-Lezak, I., et al., Monitoring the Thermal Elimination of Infiltrated Polymer from AAO Templates: An Exhaustive Characterization after Polymer Extraction. Industrial & Engineering Chemistry Research, 2011. 50(18): p. 10883-10888.
25. Masuda, H. and K. Fukuda, Ordered Metal Nanohole Arrays Made by a Two-Step Replication of Honeycomb Structures of Anodic Alumina. Science, 1995. 268(5216): p. 1466-1468.
26. Hideki, M., Y. Kouichi, and O. Atsushi, Self-Ordering of Cell Configuration of Anodic Porous Alumina with Large-Size Pores in Phosphoric Acid Solution. Japanese Journal of Applied Physics, 1998. 37(11A): p. L1340.
27. Nielsch, K., et al., Self-ordering Regimes of Porous Alumina:  The 10 Porosity Rule. Nano Letters, 2002. 2(7): p. 677-680.
28. Dersch, R., et al., Nanoprocessing of polymers: applications in medicine, sensors, catalysis, photonics. Polymers for Advanced Technologies, 2004. 16(2‐3): p. 276-282.
29. Steinhart, M., et al., Polymer Nanotubes by Wetting of Ordered Porous Templates. Science, 2002. 296(5575): p. 1997.
30. Noirez, L., et al., What Happens to Polymer Chains Confined in Rigid Cylindrical Inorganic (AAO) Nanopores. Macromolecules, 2013. 46(12): p. 4932-4936.
31. Hu, J., et al., Template method for fabricating interdigitate p-n heterojunction for organic solar cell. Nanoscale Research Letters, 2012. 7(1): p. 1-5.
32. Guan, Y., et al., Enhanced Crystallization from the Glassy State of Poly(l-lactic acid) Confined in Anodic Alumina Oxide Nanopores. Macromolecules, 2015. 48(8): p. 2526-2533.
33. Cho, Y., C. Lee, and J. Hong, Pore size effect on the formation of polymer nanotubular structures within nanoporous templates. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2014. 443: p. 195-200.
34. Ko, H.-W., et al., Fabrication of Multicomponent Polymer Nanostructures Containing PMMA Shells and Encapsulated PS Nanospheres in the Nanopores of Anodic Aluminum Oxide Templates. Macromolecular Rapid Communications, 2015. 36(5): p. 439-446.
35. Iacopino, D., et al., Highly Polarized Luminescence from β-Phase-Rich Poly(9,9-dioctylfluorene) Nanofibers. The Journal of Physical Chemistry A, 2014. 118(29): p. 5437-5442.
36. Li, L., et al., Glass Transitions of Poly(methyl methacrylate) Confined in Nanopores: Conversion of Three- and Two-Layer Models. The Journal of Physical Chemistry B, 2015. 119(15): p. 5047-5054.
37. Michell, R.M., et al., The Crystallization of Confined Polymers and Block Copolymers Infiltrated Within Alumina Nanotube Templates. Macromolecules, 2012. 45(3): p. 1517-1528.
38. Martín, J., et al., High-Aspect-Ratio and Highly Ordered 15-nm Porous Alumina Templates. ACS Applied Materials & Interfaces, 2013. 5(1): p. 72-79.
39. Vohra, V., et al., Organic solar cells based on nanoporous P3HT obtained from self-assembled P3HT: PS templates. Journal of Materials Chemistry, 2012. 22(37): p. 20017-20025.
40. Martín-González, M., et al., High-Density 40 nm Diameter Sb-Rich Bi2–xSbxTe3 Nanowire Arrays. Advanced Materials, 2003. 15(12): p. 1003-1006.
41. Martín-González, M., et al., Electrodeposition of Bi1-xSbx Films and 200-nm Wire Arrays from a Nonaqueous Solvent. Chemistry of Materials, 2003. 15(8): p. 1676-1681.
42. Martín-González, M., et al., Direct Electrodeposition of Highly Dense 50 nm Bi2Te3-ySey Nanowire Arrays. Nano Letters, 2003. 3(7): p. 973-977.
43. Martín, J., et al., Tailored polymer-based nanorods and nanotubes by "template synthesis": From preparation to applications. Polymer, 2012. 53(6): p. 1149-1166.
44. Steinhart, M., Supramolecular organization of polymeric materials in nanoporous hard templates, in Self-Assembled Nanomaterials II. 2008, Springer. p. 123-187.
45. Sirringhaus, H., et al., Two-dimensional charge transport in self-organized, high-mobility conjugated polymers. Nature, 1999. 401(6754): p. 685-688.
46. Yang, X. and J. Loos, Toward High-Performance Polymer Solar Cells:  The Importance of Morphology Control. Macromolecules, 2007. 40(5): p. 1353-1362.
47. Thompson, B.C., et al., Influence of Alkyl Substitution Pattern in Thiophene Copolymers on Composite Fullerene Solar Cell Performance. Macromolecules, 2007. 40(21): p. 7425-7428.
48. Forzani, E.S., et al., A Conducting Polymer Nanojunction Sensor for Glucose Detection. Nano Letters, 2004. 4(9): p. 1785-1788.
49. Cannon, J.P., S.D. Bearden, and S.A. Gold, Effect of wetting solvent on poly(3-hexylthiophene) (P3HT) nanotubles fabricated via template wetting. Synthetic Metals, 2010. 160(23–24): p. 2623-2627.
50. Kim, K., et al., Poly(3-hexylthiophene)/Multiwalled Carbon Hybrid Coaxial Nanotubes: Nanoscale Rectification and Photovoltaic Characteristics. ACS Nano, 2010. 4(7): p. 4197-4205.
51. Samitsu, S., et al., Field-Effect Carrier Transport in Poly(3-alkylthiophene) Nanofiber Networks and Isolated Nanofibers. Macromolecules, 2010. 43(19): p. 7891-7894.
52. Cho, S.I., et al., Nanotube-Based Ultrafast Electrochromic Display. Advanced Materials, 2005. 17(2): p. 171-175.
53. Crossland, E.J.W., et al., Anisotropic Charge Transport in Spherulitic Poly(3-hexylthiophene) Films. Advanced Materials, 2012. 24(6): p. 839-844.
54. DeLongchamp, D.M., et al., Variations in Semiconducting Polymer Microstructure and Hole Mobility with Spin-Coating Speed. Chemistry of Materials, 2005. 17(23): p. 5610-5612.
55. Kim, J.S., et al., Poly(3-hexylthiophene) Nanorods with Aligned Chain Orientation for Organic Photovoltaics. Advanced Functional Materials, 2010. 20(4): p. 540-545.
56. Byun, J., et al., Ultrahigh Density Array of Free-Standing Poly(3-hexylthiophene) Nanotubes on Conducting Substrates via Solution Wetting. Macromolecules, 2011. 44(21): p. 8558-8562.
57. Martín, J., et al., Poly (3-hexylthiophene) nanowires in porous alumina: internal structure under confinement. Soft Matter, 2014. 10(18): p. 3335-3346.
58. Martín, J., A. Nogales, and M. Martín-González, The Smectic–Isotropic Transition of P3HT Determines the Formation of Nanowires or Nanotubes into Porous Templates. Macromolecules, 2013. 46(4): p. 1477-1483.
59. Li, G., et al., " Solvent annealing" effect in polymer solar cells based on poly (3-hexylthiophene) and methanofullerenes. Advanced Functional Materials, 2007. 17(10): p. 1636.
60. Yang, H., et al., Effect of Mesoscale Crystalline Structure on the Field-Effect Mobility of Regioregular Poly(3-hexyl thiophene) in Thin-Film Transistors. Advanced Functional Materials, 2005. 15(4): p. 671-676.
61. Chang, J.-F., et al., Enhanced Mobility of Poly(3-hexylthiophene) Transistors by Spin-Coating from High-Boiling-Point Solvents. Chemistry of Materials, 2004. 16(23): p. 4772-4776.
62. Huang, L.-B., et al., Poly(3-hexylthiophene) Nanotubes with Tunable Aspect Ratios and Charge Transport Properties. ACS Applied Materials & Interfaces, 2014. 6(15): p. 11874-11881.
63. Kang, S.-J., et al., Conjugated Polymer Chain and Crystallite Orientation Induced by Vertically Aligned Carbon Nanotube Arrays. ACS Applied Materials & Interfaces, 2013. 5(18): p. 9043-9050.
64. Johnston, D.E., et al., Nanostructured Surfaces Frustrate Polymer Semiconductor Molecular Orientation. ACS Nano, 2014. 8(1): p. 243-249.
65. Chou, S.Y., P.R. Krauss, and P.J. Renstrom, Imprint of sub‐25 nm vias and trenches in polymers. Applied Physics Letters, 1995. 67(21): p. 3114-3116.
66. Chou, S.Y., P.R. Krauss, and P.J. Renstrom, 25-nanometer resolution. Science272, 1996: p. 85-87.
67. Guo, L.J., Nanoimprint Lithography: Methods and Material Requirements. Advanced Materials, 2007. 19(4): p. 495-513.
68. Ding, G., et al., Solvent-Assistant Room Temperature Nanoimprinting-Induced Molecular Orientation in Poly(3-hexylthiophene) Nanopillars. Macromolecules, 2013. 46(21): p. 8638-8643.
69. Aryal, M., K. Trivedi, and W. Hu, Nano-Confinement Induced Chain Alignment in Ordered P3HT Nanostructures Defined by Nanoimprint Lithography. ACS Nano, 2009. 3(10): p. 3085-3090.
70. Hlaing, H., et al., Nanoimprint-Induced Molecular Orientation in Semiconducting Polymer Nanostructures. ACS Nano, 2011. 5(9): p. 7532-7538.
71. Chen, D., W. Zhao, and T.P. Russell, P3HT Nanopillars for Organic Photovoltaic Devices Nanoimprinted by AAO Templates. ACS Nano, 2012. 6(2): p. 1479-1485.
72. Ihn, K.J., J. Moulton, and P. Smith, Whiskers of poly(3-alkylthiophene)s. Journal of Polymer Science Part B: Polymer Physics, 1993. 31(6): p. 735-742.
73. Berson, S., et al., Poly(3-hexylthiophene) Fibers for Photovoltaic Applications. Advanced Functional Materials, 2007. 17(8): p. 1377-1384.
74. Li, L., G. Lu, and X. Yang, Improving performance of polymer photovoltaic devices using an annealing-free approach via construction of ordered aggregates in solution. Journal of Materials Chemistry, 2008. 18(17): p. 1984-1990.
75. Li, L., et al., Poly(3-hexylthiophene) nanofiber networks for enhancing the morphology stability of polymer solar cells. Organic Electronics, 2013. 14(5): p. 1383-1390.
76. Gurau, M.C., et al., Measuring Molecular Order in Poly(3-alkylthiophene) Thin Films with Polarizing Spectroscopies. Langmuir, 2007. 23(2): p. 834-842.
77. Yamamoto, T., et al., Extensive Studies on π-Stacking of Poly(3-alkylthiophene-2,5-diyl)s and Poly(4-alkylthiazole-2,5-diyl)s by Optical Spectroscopy, NMR Analysis, Light Scattering Analysis, and X-ray Crystallography. Journal of the American Chemical Society, 1998. 120(9): p. 2047-2058.
78. Yang, X., et al., Crystalline Organization of a Methanofullerene as Used for Plastic Solar-Cell Applications. Advanced Materials, 2004. 16(9-10): p. 802-806.
79. Chen, C.-Y., et al., Formation and Thermally-Induced Disruption of Nanowhiskers in Poly(3-hexylthiophene)/Xylene Gel Studied by Small-Angle X-ray Scattering. Macromolecules, 2010. 43(17): p. 7305-7311.