利用調幅式微差掃描卡儀(Temperature Modulated Differential Scanning Calorimeter, TMDSC)中的傳統(conventional)與調制(modulated)兩種模式探討50/50等組成對苯二甲酸二乙酯(PET)與對苯二甲酸二丙酯(PTT)無規共聚酯之等溫結晶和等溫結晶後之熔融行為，並以偏光顯微鏡(Polarizing Light Microscope, PLM)觀察其球晶成長速率及結晶形態。等溫溫度在115至142℃範圍中，Avrami 指數n1隨著等溫結晶溫度升高，由3.00增加至3.22，在最高溫時結晶應屬於自發成核且n1值等於4，由於此樣品之緩慢結晶速率使得一級結晶和二級結晶在高結晶溫度時同時發生而降低n1指數。另外分別以10、2℃/min加熱速率經由兩種微差熱掃描模式中皆可觀察到三根或兩根熔融峰之多重熔融行為。由廣角X光繞射(WAXD)、DSC和TMDSC的結果證實此樣品具雙形態和熔融-再結晶-再熔融兩種熔融機制共同存在。將可逆熱流所得之一級結晶熔融峰溫度以Hoffman-Weeks線性外插求得此樣品之平衡熔點為176.6℃。此外，此樣品可以成功地將結晶一半所需的時間(t1/2)之倒數作為總體結晶速率代替球晶成長速率作regime II → III轉移分析，兩種方法求得的轉移溫度132℃與偏光顯微鏡所觀察到由規則性球晶轉變為有環狀消光條紋球晶的溫度相吻合。
選用鄰苯二甲酸二丁酯低熔點之溶劑且PET/PTT含量較少之72PT/28ET、62PT/38ET和50PT/50ET共聚酯，利用高分子－稀釋劑之熔融溫度下降方法求取百分百結晶的熔融焓(ΔHf)及非常稀釋時每單位cc之混合熱(B)。實驗結果分別得到4.48、3.43和3.07 kcal/mole，而B值則為3.90、2.85和2.75 cal/cc。

The crystallization kinetics and the melting behavior of a random copolyester with equal amounts of ethylene- and trimethylene- terephthalate units were studied by using a modulated differential scanning calorimeter in both conventional mode (DSC) and modulated mode (TMDSC). Polarizing light microscope (PLM) was used to study the spherulite growth rates and spherulite patterns. Isothermal crystallization was performed at temperatures (TC) between 115 and 142℃. The Avrami exponents, n1, were found to increase from 3.00 to 3.22 with an increasing TC. At the highest TC, it should be a sporadic nucleation with spherical growth, i.e. n1 = 4. The value of n1 less than 4 and the slow rate of crystallization indicate that both primary and secondary crystallization occurs in parallel rather than in series. Triple- and double- melting peaks were observed for the melting behavior of DSC at 10℃/min and of TMDSC at 2℃/min. The results of WAXD, DSC and TMDSC indicate the coexistence of two melting mechanisms, i.e., dual morphologies and the recrystallization process. The Hoffman-Weeks plot gave an equilibrium melting temperature of 176.6℃ from the reversing curves of TMDSC. In this study, the regime II→III transition temperature can be estimated from the inverse of the half-time of crystallization as overall growth rate and the growth rate. Meanwhile, a clear change in morphology from negative regular to banded spherulites was also observed around 132℃ by using PLM.
The heat of fusion of polymer is customarily evaluated through the melting point depression measurements with the thermodynamic melting points. Application of the Flory equation to the PET/PTT random copolyesters diluted with di-n-butyl phthalate gave the values of the heat of fusion to be 4.48, 3.43 and 3.07 kcal/mole, respectively, for the random copolyesters containing 28, 38 and 50 mole % of ethylene terephthalate unit. The corresponded values of the interaction energy of mixing at infinite dilution were 3.90, 2.85 and 2.75 cal/cc.

Contents
摘要 I
Abstract II
Contents III
List of Tables V
List of Figures VII
1. Introduction 1
2. Literature review 5
2.1. Isothermal Crystallization Kinetics Analysis 5
2.1.1. Avrami Analysis 5
2.1.2. Multiple endotherm behavior 6
2.1.3. Temperature-modulated differential scanning calorimeter (TMDSC) 7
2.1.4. Interpretation of TMDSC 8
2.1.5. Equilibrium melting temperature 9
2.1.6. Regime transition 10
2.1.7. Polarized light microscopy (PLM) 12
2.1.8. Mechanism of spherulite formation 15
2.2. Heat of fusion 15
3. Experimental 18
3.1. Materials 18
3.2. Instruments 18
3.3. Sample preparation 18
3.4. Isothermal crystallization kinetics 18
3.4.1. Melting condition 19
3.4.2. Isothermal crystallization (in conventional mode) 19
3.4.3. Modulation Period 19
3.4.4. Melting Behavior 20
3. 5. Polarized light microscopy (PLM) 20
3.5. Heat of fusion (ΔHf) 22
4. Results and discussion 23
4.1. Copolyester containing 49.9% trimethylene- and 50.1% ethylene- units 23
4.1.1. WAXD analyses 23
4.1.2. Isothermal crystallization kinetics 23
4.1.3. The origin of multiple melting peaks 24
4.1.4. Equilibrium melting temperature 27
4.1.5. Regime transition 28
4.1.6. Growth rates of spherulites 28
4.1.7. Existence of regime II → III transition 29
4.1.8. Spherulitic morphology 30
4.2. Heat of fusion of a copolyester containing 71.8% trimethylene- and 28.2% ethylene- units 30
4.3. Heat of fusion of a copolyester containing 62.1% trimethylene- and 37.9% ethylene- units 32
4.4. Heat of fusion of a copolyester containing 49.9% trimethylene- and 50.1% ethylene- units 33
5. Conclusion 36
Reference 38

Reference
1. Tseng, I. M.; Huang, J. C.; Juang, C. Processes for 1,3-Propanediol and Poly(Propylene Terephthalate) Manufacture. Chemical Information Monthly, 1998, 12(6), 24-38. (in Chinese)
2. Wang, C. L., Crystallization Kinetics Analysis and Morphology of Poly[(ethylene) -co-(trimethylene terephathalate)]s, National Sun Yat-Sen University, Kaohsiung, Taiwan R.O.C., Master Thesis (in Chinese), 2003.
3. Flory, P. J., Mandelkern, L. and Hall, H. K., Crystallization in high polymers. VII. Heat of fusion of poly-(N,N’-sebacoylpiperazine) and its interaction with diluents, J. Am. Chem. Soc., 1951, 73, 2532-2538.
4. Mandelkern, L. and Flory, P. J., Melting and glassy state transition in cellulose esters and their mixtures with diluents, J. Am. Chem. Soc., 1951, 73, 3206-3212.
5. Mandelkern, L., Garrett, R. R., and Flory, P. J., Heats of fusion of aliphatic polyesters, J. Am. Chem. Soc., 1952, 74, 3949-3951.
6. Krigbaum, W. R. and Uematsu, I., Heat and entropy of fusion of isotactic polypropylene, J. Polym. Sci., Part A, 1965, 3, 767-776.
7. Danusso, F. and Gianotti, G., Fusion enthalpy and entropy of isotactic polypropylene, Eur. Polym. J., 1968, 4, 165-170.
8. Shi, G.-Y., Huang, B. and Zhang, J.-Y., Enthplty of fusion and equilibrium melting point of the β–form of polypropylene, Makromol. Chem., Rapid Commun., 1984, 5, 573-578.
9. Malik, S. and Nandi, A. K., Crystallization mechanism of regioregular poly(3- alkyl thiophene)s, J. Polym. Sci., Part B: Polym. Phys., 2002, 40, 2073-2085.
10. Zhou, C.; Clough, S. B. Multiple Melting Endotherms of Poly(Ethylene Terephthalate). Polym. Engng. Sci., 1988, 28(2), 65-68.
11. Kampert, W. G., Sauer, B. B., Temperature Modulated DSC Studies of Melting and Recrystallization in Poly(oxy-1,4-phenyleneoxy-1,4-phenylenecarbonyl-1,4- phenylene), Polym, Engng. Sci., 2001, 41, 1714-1730.
12. Yuan, Z., Song, R., Shen, D., Study of Multiple Melting Behavior of Syndiotatic Polystyrene in β-crystalline form, Polym. Int., 2000, 49, 1377-1382.
13. Wang, Z. G., Hsiao, B. S., Sauer, B. B., Kampert, W. G., The Nature of Secondary Crystallization in Poly(ethylene terephthalate), Polymer, 1999, 40, 4615-4627.
14. Kampert, W. G., Sauer, B. B., Temperature Modulated DSC Studies of Melting and Recrystallization in Poly(ethylene-2,6-naphthalene dicarboxylate) (PEN) and blends with Poly(ethylene terephthalate) (PET), Polymer, 2001, 42, 8703-8714.
15. Sauer, B. B., Kampert, W. G., Neal Blanchard, E., Threefoot, S. A., Hsiao, B. S., Temperature Modulated DSC Studies of Melting and Recrystallization in Polymers Exhibiting Multiple Endotherms, Polymer, 2000, 41, 1099-1108.
16. Wunderlich, B., Macromolecular physics, volume 3, Crystal melting, Academic Press: New York, 1980.
17. Medellín-Rodríguez, F. J.; Phillips, P. J.; Lin, J. S. Melting Behavior of High- Temperature Polymers. Macromolecules, 1996, 29, 7491-7501.
18. Yasuniwa, M., Tsubakihara, S., Ohoshita, K., Tokudome, S., T., X-ray Studies on the Double Melting Behavior of Poly(butylenes terephthlate), J. Polym. Sci., Part B: Polym. Phys., 2001, 39, 2005-2015.
19. Hobbs, S.Y., Pratt, C.F. Multiple Melting in Poly(butylene terephthalate), Polymer, 1975, 16, 462-464.
20. Nichols, M. E., Robertson R. E., The Multiple Melting Endotherms from Poly(butylene terephthalate), J. Polym. Sci., Part B: Polym. Phys., 1992, 30, 755-768.
21. Xu, J., Feng, L., Liu, Z., Chen, L., Deng, Y., Cui, C., Chen, W., Nonisothermal Crystallization of s-PP Fraction, J. Appl. Polym. Sci., 1999, 71, 897-901.
22. Papageorgiou, George Z., Karayannidis George P., Multiple Melting Behavior of Poly(ethylene-co-butylene naphthalene-2,6-dicarboxylate)s, Polymer, 1999, 40, 5325-5332.
23. Righetti, M. C., Pizzoli, M., Crystallization and Melting Behavior of Poly(butylenes adipate), Poly(butylenes isophthalate) and their copolymers, Macromol. Chem. Phys. 1998, 199, 2063-2070.
24. Finelli, L., Lotti N., Munari, A., Crystallization Kinetics and Melting Behavior of Poly(butylenes isophthalate/terephthalate) random copolyesters, Eur. Polym. J., 2001, 37, 2039-2046.
25. Finelli, L., Lotti, N., Righetti, M.C., Munari, A. Melting Behavior and Crystallization Kinetics of Poly(butylenes terephthalate-co-diethylene terephthalate) and Poly(butylenes terephthalate-co-triethylene terephthalate) Copolyester, J. Appl. Polym. Sci., 2001, 81, 3545-3551.
26. Wu, T.-M., Chang C.-C., Yu, L. T., Crystallization of Poly(ethylene terethphalate -co-isophthalate), J. Polym. Sci., Part B: Polym. Phys., 2000, 38, 2515-2524.
27. Lotti N., Finelli, L., Siracusa V., Munari A., Gazzano, M., Synthesis and Thermal Characterization of Poly(butylenes terephthalate-co-thiodiethylene terephthalate) Copolyesters, Polymer, 2002, 43, 4355-4363.
28. Samuels, R. J., Quantitative Structure Characterization of the Melting Behavior of Isotactic Polypropylene, J. Polym. Sci. Polym. Phys. Ed., 1975, 13, 1417-1446.
29. Prest, Jr. W. M., Luca, D. J., The Morphology and Thermal Response of High-temperature-crystallized Poly(Vinylidene Fluoride), Appl. Phys.,1975, 46, 4136-4143.
30. Stein, R. S., Misra, A., Morphological Studies on Polybutylene Terephthalate, J. Polym. Sci. Polym. Phys. Ed., 1980, 18, 327-342.
31. Ludwig, H.-J., Eyerer, P., Influence of the Processing Condition on Morphology and Deformation Behavior of Poly(Butylene Terephthalate)(PBT), Polym. Engng. Sci., 1988, 28, 143-146.
32. Reading, M., Modulated Differential Scanning Calorimetry - A New Way Forward in Materials Characterization, Trends Polym. Sci., 1993, 8, 248-253.
33. Reading, M., Elliot, D, Hill, V. L., A New Approach to the Calorimetric Investigation of Physical and Chemical-Transition, J. Therm. Anal., 1993, 40, 929-955.
34. Okazaki, I., Wunderlich, B., Reversible Local Melting in Polymer Crystals, Macromol. Rapid Commun., 1997, 18, 313-318.
35. Okazaki, I., Wunderlich, B., Reversible Melting in Polymer Crystals Detected by Temperature-Modulated Differential Scanning Calorimeter, Macromolecules, 1997, 30, 1758-1764.
36. Hoffman, J. D.; Weeks, J. J., Melting Process and the Equilibrium Melting Temperature of Polychlorotrifluoroethylene, J. Res. Natl. Bur. Stand. (U. S.), 1962, 66A, 13-28.
37. Lu, X. F.; Hay, J. N. Isothermal Crystallization Kinetics and Melting Behaviour of Poly(Ethylene Terephthalate). Polymer, 2001, 42, 9423-9431.
38. Huang, J. M.; Chang, F. C. Crystallization Kinetics of Poly (Trimethylene Terephthalate). J. Polym. Sci., Part B: Polym. Phys., 2000, 38, 934-941.
39. Hoffamn, J. D.; Davis, G. T.; Lauritzen, J. I., Jr. Crystalline and Noncrystalline Solids. In Treatise on Solid State Chemistry; Hannay, N. B., Eds.; Plenum: New York, 1976; Vol. 3, Chapter 7.
40. Lovinger, A. J.; Davis, D. D.; Padden, F. J., Jr. Kinetic Analysis of the Crystallization of Poly(