本研究主要包括兩部分。第一部分，材料為聚丁二酸二丁酯及含少量丁二酸-1,4-環己烷二甲基酯之兩種聚丁二酸二丁酯共聚酯(PBCSu9505, PBCSu9010)。由核磁共振分析 (1HNMR) 光譜得知，此兩種共聚酯其丁二酸-1,4-環己烷二甲基酯含量分別為5.7及12.0 mol%，而針對丁二酸-1,4-環己烷二甲基酯之順反異構物含量來分析，順式比例約70.5%。利用示差掃描熱卡計(DSC)與可控溫偏光顯微鏡(PLM)以不同降溫速率來討論非等溫結晶行為。在DSC的部分，利用多種非等溫結晶動力學模組來探討不同降溫速率與丁二酸-1,4-環己烷二甲基酯的含量對結晶速率參數的影響，而在PLM的部分，以非等溫結晶所量測之球晶成長速率利用Laurizen-Hoffman方程式估計三種樣品之regime II到regime III之轉換溫度。當非等溫結晶完成後，利用廣角X光繞射(WAXD)及小角度X光散射(SAXS)探討不同降溫速率與丁二酸-1,4-環己烷二甲基酯的含量對結晶構造及結晶層板的影響。
透過以上的分析可以發現，增加降溫速率則結晶溫區將變廣並增加結晶速度。針對結晶溫區變廣，由層板結構分析可以發現層板大小分布會隨增加降溫速率而變廣；針對結晶速度增加，平均層板大小將隨增加降溫速率而變小，主要是因為增加降溫速率會使結晶在過冷度較大的條件下生長，雖然成長速度快但也比較沒有完整性使平均結晶層板大小降低。隨後，以DSC升溫將不同降溫速率所得之非等溫結晶熔融，並討論多重熔峰現象與結晶層板大小的關係。此外，加入少量的丁二酸-1,4-環己烷二甲基酯會抑制聚丁二酸二丁酯的結晶能力。以WAXD對結晶構造分析，我們認為丁二酸-1,4-環己烷二甲基酯並不會參與結晶，換句話說，結晶發生時丁二酸-1,4-環己烷二甲基酯將會被排除在結晶層之外。
第二部分將透過可控溫傅利葉轉換紅外線光譜儀(Temperature-resolved FTIR)探討層板結構的形成。首先針對三種樣品在其結晶成長的狀態下(非等溫結晶成長)觀察CH及C=O鍵吸收區間(3050-2800cm-1、1800-1650cm-1)特徵峰的變化情形並做定性分析。在CH吸收區間，當丁二酸-1,4-環己烷二甲基酯含量增加時，約在2854cm-1 的吸收強度有明顯上升而此特徵峰我們認為是1,4-環己烷二甲基上的C-H單鍵所貢獻的。當結晶成長時，屬於非晶態的C-H2在2962與2858cm-1皆發生特徵峰分裂行為(crystal field splitting)，這種現象是因為C-H2處在不同環境下(結晶或非晶態)而使特徵峰有所位移。在C=O吸收區間，由C=O受不同環境下而使特徵峰有所位移之原理判定層板由結晶層、非晶層及邊界層所組成，而此邊界層為結晶層與非晶層的交界處。利用二維紅外線光譜儀相關性分析(2D-IR correlation analysis)發現，當丁二酸-1,4-環己烷二甲基酯含量增加時所形成之邊界層變得不明顯，藉由升溫觀察C=O吸收區間變化情形，我們發現邊界層的熱穩定性也變得更差。我們認為當丁二酸-1,4-環己烷二甲基酯含量增加而影響邊界層，與第一部分所提到結晶發生時丁二酸-1,4-環己烷二甲基酯會被排除在結晶層之外有關連性，而此議題也將在本研究中討論。

Poly(butylene succinate-co-1,4-cyclohexanedimethylene succinate) [PBCSu] were synthesized via a two-stage condensation reaction. PBCSu9505 and PBCSu9010 were characterized as having 5.6 and 12 mol% 1,4-cyclohexanedimethylene succinate (CS) units, respectively, by 1H NMR. Copolymers were characterized as random, based on 13C NMR spectra. A differential scanning calorimeter (DSC) and a polarized light microscope (PLM) were adapted to study the nonisothermal crystallization and melting behaviors of these copolymers. DSC data were analyzed via modified Avrami, Ozawa, and Mo models, respectively. Morphologies and growth of spherulites were monitored under PLM experiments at constant cooling rates. Isothermal growth rates obtained via nonisothermal method were analyzed using secondary nucleation theory. The regime transition temperature from II to III was found at 85.2 and 79.6 °C for PBCSu9505 and PBCSu9010, respectively. The results of PLM and DSC demonstrate that incorporation of minor CS units into PBSu inhibits the crystallization rate and crystallinity of the resulting copolyester. Small angle X-ray scattering (SAXS) and wide angle X-ray diffraction (WAXD) were used to analyze the lamellar and crystal structures of nonisothermally crystallized copolymers, respectively. Long period (L) and crystal thickness (lc) were found to decrease with increasing the cooling rate. However, the peak positions of WAXD patterns do not change with various cooling rates or the amount of CS units. It revealed that there was only one crystal form in this study and CS units were excluded from the crystal lamellae.
Temperature-resolved FTIR was used to monitor the spectral variations during the nonisothermal crystallization process of PBSu and PBCSu copolymers. Different wavenumber regions (C-H and C=O stretching) were compared by second derivatives and two dimensional (2D) correlation analysis. The characteristic bands of crystalline and amorphous were identified in each region. In addition, C=O stretching region was also monitored to study the melting process. It was observed that the melting- recrystallization-remelting process occurred at boundary phase between the crystalline and amorphous regions. By 2D synchronous correlation analysis, it was found that the intensity change at 1723 cm-1, which is assigned to boundary phase, decreases with increasing the amount of CS units. It revealed that the crystallinity of boundary phase was restricted by the CS units excluded from the crystal lamellae. Thus, the thermal stability of boundary phase decreased with increasing the amount of CS units

誌謝 II
摘要 III
Abstract V
Contents VI
List of Figures X
List of Tables XIV
Chapter 1 Introduction 1
1.1 Backgrounds 1
1.2 Motivation and objectives 2
Chapter 2 Literature Review and Theoretical Approaches 4
2.1 Related researches about poly(butylene succinate) and its copolymers 4
2.1.1 Crystallization structure and conformation of poly(butylene succinate 4
2.1.2 Poly(butylene succinate) homopolymer 4
2.1.3 Copolymerization of poly(butylene succinate) 6
2.2 Development of 1,4-cyclohexanedimethanol 7
2.2.1 Related researches of 1,4-cyclohexanedimethanol 7
2.2.2 Related researches of poly(butylene succinate-co-1,4-cyclohexanedime- thylene succinate) 9
2.3 Nonisothermal crystallization kinetics 10
2.3.1 Avrami model 11
2.3.2 Ozawa model 12
2.3.3 Mo model 12
2.3.4 Kinetic analysis of growth rates of spherulite 13
2.4 Multiple melting behavior 14
2.4.1 Melting-recrystallization-remelting 14
2.4.2 Dual morphology 15
2.4.3 Hybrid theory 15
2.5 Small angle X-ray scattering theory 15
2.6 Temperature-resolved FTIR 16
2.7 Related researches boundary phase 17
Chapter 3 Experimental 19
3.1 Materials and basic properties 19
3.2 Samples preparation 19
3.3 Instruments 19
3.4 Determination of cis/trans conformation for 1,4-cyclohexanedimethanol using 1H NMR 20
3.5 Measurement of growth rate and observation of morphology using PLM via nonisothermal crystallization method 21
3.6 Investigation of nonisothermal crystallization behavior using DSC 21
3.7 Investigation of crystal structure following nonisothermal crystallization using WAXD 22
3.8 Investigation of crystal lamellae following nonisothermal crystallization using SAXS 22
3.9 Investigation nonisothermal crystallization behavior using temperature- resolved FTIR 23
3.10 Investigation of multiple melting behavior using temperature-resolved FTIR 23
3.11 2D IR correlation analysis 24
3.12 Research procedures 25
Chapter 4 Results and Discussion 26
4.1 Analysis of cis/trans conformation of 1,4-cyclohexanedimethanol for PBCSu copolymer 26
4.2 Growth rates and morphology 26
4.2.1 Determination of growth rate by nonisothermal crystallization method 26
4.2.2 Kinetic analysis of growth rate of spherulites 27
4.2.3 Morphology of spherulites 28
4.3 Nonisothermal crystallization 29
4.3.1 Crystallization behavior 29
4.3.2 Analysis of Avrami model 30
4.3.3 Analysis of Ozawa model 31
4.3.4 Analysis of Mo model 31
4.4 WAXS analysis 32
4.5 SAXS analysis 32
4.5.1 1-D SAXS profiles 32
4.5.2 Lorentz-corrected SAXS profiles 33
4.5.3 1-D correlation function analysis 35
4.6 Melting behavior 35
4.7 Temperature-resolved FTIR analysis 37
4.7.1 Characterization 37
4.7.1.1 CH stretching region 37
4.7.1.2 C=O stretching region 38
4.7.2 2D IR correlation analysis 41
4.7.3 Melting behavior at C=O stretching region 43
Chapter 5 Conclusions 46
References 84
Appendix 92

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