聚(3-羥基丁酯-co-4-羥基丁酯) (poly(3-hydroxybutyrate-co-4-hydroxybutyrate) , P34HB)主要是藉由細菌發酵生產的生物可降解聚酯高分子。高分子量P34HB和另一種可生物降解的聚乳酸(poly(lactic acid), PLA)的摻合物通常無法混溶。但藉由降低P34HB的分子量，低分子量P34HB可以改善與PLA的相容性。本實驗藉由甲醇降解以及混煉熱解的方式製備低分子量的P34HB。分別在40、50和60°C下研究P34HB的醇解動力學，發現其遵循一級反應，速率常數在1.00至1.27×10-4 1/min的範圍內，並且從Arrhenius圖得出的活化能為10.37 kJ / mol。另外利用熔融混煉方式製備m-P34HB/PLA摻合物，結果發現在各比例的玻璃轉移溫度（Tg）皆些微下降，證明藉由降低P34HB的分子量可改善相容性。由於熔融混煉下降解的P34HB具有相對較低的Tg，因此可為PLA提供增塑效果，並降低了PLA的結晶溫度。隨著摻合物中P34HB含量增加到20％，斷裂伸長率可從純PLA的2.36％顯著增加到146％。藉由SEM觀察m-P34HB/PLA薄膜表面，可以得知當m-P34HB/PLA比例於25/75時，其表面孔洞大量增加，代表當25%的P34HB摻入時，會有明顯的相分離，使得其斷裂伸長率不會再增加。此外，本研究以蛋白酶k進行酵素生物分解實驗，其結果顯示，當P34HB的摻入會讓摻合物的降解趨勢下降，經過14天降解，純PLA的重量殘存率為42.5%，而m-P34HB/PLA摻合物(20/80)的重量殘存量為63.3%，代表P34HB的摻入會使PLA的降解趨緩。

Poly(3-hydroxybutyrate-co-4-hydroxybutyrate) is mainly produced by bacterial fermentation and is a biodegradable polyester. Biodegradable polymer blends of high molecular weight poly (3-hydroxybutyrate-co-4-hydroxybutyrate) (P34HB) and polylactic acid (PLA) are generally immiscible. However, by lowering the molecular weight of P34HB, the low molecular weight P34HB has improved miscibility with PLA. In this experiment, low molecular weight P34HB was prepared by methanolysis degradation and melting-blends. The alcoholysis kinetics of P34HB was studied at 40, 50 and 60 ° C and found to follow the first order reaction. The rate constants were in the range of 1.00 to 1.27 × 10-4 1/min, and the activation energy derived from the Arrhenius plot was 10.37 kJ / mol. For the m-P34HB/PLA blends obtained by melt blending, the glass transition temperature (Tg) of the PLA component decreased slightly, which proved that the compatibility was improved by reducing the molecular weight of P34HB. Because the degraded P34HB had a relatively low Tg, it could provide PLA with a plasticizing effect and reduced the crystallization temperature. In addition, as the P34HB content in the blend increased to 20%, the elongation at break increased significantly from 2.36% to 146%. By observing the surface of the m-P34HB/PLA film by SEM, it could be seen that when the m-P34HB/PLA ratio was 25/75, the surface pores increased greatly. This indicated that addition of 25% of P34HB could result in obvious phase separation , and therefore the elongation at break would not increase further. The P34HB component in the blends had a higher degradation temperature than the pure P34HB. In addition, in this study, the enzymatic degradation was carried out using proteinase k, and the results showed that when P34HB was incorporated, the tendency of the blend to be degraded decreased. After 14 days of degradation of pure PLA, the residual weight was 42.5% , and the PLA component in the m-P34HB/PLA blends (20/80) had a residual weight of 63.3%, indicating that the incorporation of P34HB could slow the degradation of PLA.

中文摘要：	I
英文摘要:	   III
目錄	V
圖目錄	IX
表目錄	XX
第一章 緒論	1
1.1前言	1
1.2研究目的與動機	1
第二章 文獻回顧	3
2.1生物可分解高分子	3
2.1.1 生物可分解高分子的種類	4
2.2聚乳酸Poly(lactic acid)(PLA)簡介	6
2.2.1 PLA的歷史發展	6
2.2.2 PLA之性質與特性	6
2.2.3 PLA的應用	7
2.3聚羥基烷酯類Poly(hydroxyalkanoates)(PHAs)簡介	8
2.3.1 PHAs的歷史發展	8
2.3.2 PHAs的種類	8
2.4高分子摻合物	9
2.4.1摻合物的製備方法	9
2.4.2摻合物之相容性	12
2.4.2.1由玻璃轉移溫度來檢測其相容性	12
2.4.2.2平衡熔點的下降與測量	14
2.5聚乳酸的摻合物研究	15
2.6聚羥基烷酯類的摻合	16
2.7聚乳酸與聚羥基烷酯類摻合	18
2.8生物可分解高分子的分解機制	20
第三章 實驗藥品與方法	22
3.1實驗藥品	22
3.2實驗儀器	24
3.3實驗步驟	28
3.3.1製備寡聚物P34HB	28
3.3.1.1 利用甲醇降解P34HB製備A-P34HB寡聚物	28
3.3.1.2 利用熱降解P34HB製備T-P34HB寡聚物	28
3.3.1.3 利用溶劑法製備PLA/P34HB的摻合物	28
3.3.2利用熔融混練法製備m-P34HB/PLA摻合物	29
3.3.3Tris-HCl buffer的製備	29
3.4結構分析與性質測試	30
3.4.1 P34HB寡聚物的組成與分子量分析(NMR)	30
3.4.2分子量與分子量分布(GPC)	30
3.4.3 P34HB/PLA摻混物的熱轉移性質與相容性(DSC分析)	30
3.4.4熱重損失測試 (TGA)	31
3.4.5拉伸機械性質 (Tensile mechanical properties)	31
3.4.6耐衝擊測試 (impact resistance properties)	32
3.4.7薄膜形態觀察 (SEM)	32
3.4.8 m-P34HB/PLA摻混物薄膜結構分析(FTIR-ATR)	33
3.4.9結晶構造分析(XRD)	33
3.4.10動態機械測試(Dynamic Mechanical Analyzer,DMA)	33
3.4.11酵素分解m-P34HB/PLA薄膜實驗(蛋白酶K)	33
3.4.12酵素分解m-P34HB/PLA薄膜實驗(脂肪酶)	34
第四章 結果與討論	35
4.1 P34HB醇解產物及醇解反應動力學研究	35
4.1.1醇解產物A-P34HB的分子量	37
4.1.2 P34HB的醇解反應動力學	44
4.2 P34HB的熱裂解寡聚物(T-P34HB)與PLA的相容性研究	53
4.2.1 P34HB熱裂解產物的分子量分析	54
4.2.2 T-P34HB寡聚物的熱轉移性質	56
4.2.3 T-P34HB的玻璃轉移溫度研究	58
4.2.4 PLA與T-P34HB的相容性分析	59
4.3 熔融混煉法製備m-P34HB/PLA摻合物研究	63
4.3.1 m-P34HB/PLA摻合物的分子量與分子量分布測量(GPC)	63
4.3.2 m-P34HB/PLA摻合物的熱轉移性質與相容性	66
4.3.3 m-P34HB/PLA摻合物的熱重損失測試 (TGA)	69
4.3.4 摻合物的拉伸機械性質 (Tensile mechanical properties)	72
4.3.5 m-P34HB/PLA的薄膜形態觀察與分析(SEM)	77
4.3.6 m-P34HB/PLA的薄膜化學結構鑑定(ATR)	86
4.3.7 m-P34HB/PLA薄膜的結晶構造分析(XRD)	88
4.3.8 m-P34HB/PLA摻合物的動態機械測試(DMA)	89
4.3.9 m-P34HB/PLA薄膜的蛋白酶k酵素分解	92
4.3.10 m-P34HB/PLA薄膜的脂肪酶酵素分解	113
第五章 結論	131
第六章 建議事項	133
第七章 參考文獻	134
附錄	144
附錄1不同溫度下以甲醇醇解P34HB之組成分析(NMR)	144
附錄2不同比例下P34HB/CAB以及P34HB/CAP之相容性	149
附錄3不同比例之P34HB其性質變化表	154
附錄3不同實驗方法之P34HB熱性質變化	157
附錄4醇解動力學	159
附錄參考文獻	167
 
圖目錄
Figure 2.1生物可分解高分子的分解方式	3
Figure 2.2自然界中PHAs的生物合成和生物降解循環	4
Figure 2.3不同的PLA合成方法	5
Figure 2.4由不同比例所形成的丙交酯	7
Figure 2.5常見的PHA結構圖	9
Figure 2.6溶劑法將有機/無機高分子摻混成奈米複合材料示意圖	10
Figure 2.7熔融共混插入法將有機/無機高分子摻混成奈米複合材料示意圖	11
Figure 2.8乳膠摻混法將有機/無機高分子摻混成奈米複合材料示意圖	11
Figure 2.9 IPN形成的示意圖(a)同步交聯、(b)順序交聯及(c)選擇性交聯	12
Figure 2.10藉由DSC判斷摻合物之相容性	14
Figure 2.11 Gibbs–Thomson equation作圖	14
Figure 2.12 Hoffman-Weeks equation作圖	15
Figure 2.13常見可降解聚乳酸與聚羥基烷酯類的微生物	21
Figure 2.14表面侵蝕與整體侵蝕示意圖	21
Figure 3.1 ASTM D 638 Type IV標準試片圖	31
Figure 3.2 ASTM D 256標準試片圖	32
Figure 4.1 P34HB高分子鏈中3HB-3HB結構之醇解機制	35
Figure 4.2 P34HB高分子鏈中3HB-4HB結構之醇解機制	36
Figure 4.3 P34HB高分子鏈中4HB-4HB結構之醇解機制	36
Figure 4.4 1H NMR spectrum of P34HB.	40
Figure 4.5 H-NMR spectrum of A-P34HB oligomer obtained by methanolysis (H2SO4/CH3OH=5/95, 50 mL) at 40oC for 20 min.	40
Figure 4.6 H-NMR spectrum of A-P34HB oligomer obtained by methanolysis (H2SO4/CH3OH=5/95, 50 mL) at 40 oC for 40 min.	41
Figure 4.7 H-NMR spectrum of A-P34HB oligomer obtained by methanolysis (H2SO4/CH3OH=5/95, 50 mL) at 40 oC for 60 min.	41
Figure 4.8 H-NMR spectrum of A-P34HB oligomer obtained by methanolysis (H2SO4/CH3OH=5/95, 50 mL) at 40 oC for 80 min.	42
Figure 4.9 H-NMR spectrum of A-P34HB oligomer obtained by methanolysis (H2SO4/CH3OH=5/95, 50 mL) at 40 oC for 120 min.	42
Figure 4.10不同反應溫度A-P34HB的Mn與反應時間之關係圖	43
Figure 4.11不同反應溫度A-P34HB的4HB含量與反應時間之關係圖	43
Figure 4.12 Linear plot of ln(1–1/ DP) with reaction time according to the first-order degradation reaction of methanolysis at 40 °C. The complex rate constant obtained was 1.00×10-4 1/min.	45
Figure 4.13 Linear plot of ln(1–1/ DP) with reaction time according to the first-order degradation reaction of methanolysis at 50 °C. The complex rate constant obtained was 1.15×10-4 1/min.	45
Figure 4.14 Linear plot of ln(1–1/ DP) with reaction time according to the first-order degradation reaction of methanolysis at 60 °C. The complex rate constant obtained was 1.27×10-4 1/min.	46
Figure 4.15 Arrhenius plot of lnk vs. 1/T of methanolysis reaction of P34HB	47
Figure 4.16 Linear plot of ln(1-1 / DP3HB) versus reaction time, based on a methanolysis degradation reaction at 40 °C. The complex constant obtained was 1.12×10-4 1 / min.	48
Figure 4.17 Linear plot of ln(1-1 / DP4HB) versus reaction time, based on a methanolysis degradation reaction at 40 °C. The complex constant obtained was 1.01×10-3 1 / min.	48
Figure 4.18 Linear plot of ln(1-1 / DP3HB) versus reaction time, based on a methanolysis degradation reaction at 50 °C. The complex constant obtained was 1.23×10-4 1 / min.	49
Figure 4.19 Linear plot of ln(1-1 / DP4HB) versus reaction time, based on a methanolysis degradation reaction at 50 °C. The complex constant obtained was 1.66×10-3 1 / min.	49
Figure 4.20 Linear plot of ln(1-1 / DP3HB) versus reaction time, based on a methanolysis degradation reaction at 60 °C. The complex constant obtained was 1.33×10-4 1 / min.	50
Figure 4.21Linear plot of ln(1-1 / DP4HB) versus reaction time, based on a methanolysis degradation reaction at 60 °C. The complex constant obtained was 2.22×10-3 1 / min.	50
Figure 4.22 Arrhenius plot of lnk vs. 1/T of methanolysis reaction of 3HB	51
Figure 4.23 Arrhenius plot of lnk vs. 1/T of methanolysis reaction of 4HB	51
Figure 4.24 P34HB高分子鏈中3HB-3HB單元之熱裂解機制	53
Figure 4.25 P34HB高分子鏈中3HB-4HB單元之熱裂解機制	53
Figure 4.26 P34HB高分子鏈中4HB-4HB單元之熱裂解機制	54
Figure 4.27 H-NMR spectrum of T-P34HB oligomer obtained by 120 min under thermal degradation temperature of 170 oC.	55
Figure 4.28 The second DSC heating curves of P34HB and various T-P34HB oligomers obtained from the thermal degradation of P34HB for different times at 170 °C.	57
Figure 4.29 The change of glass transition temperature (Tg) with molecular weight of T-P34HB.	58
Figure 4.30 Linear plot of glass transition temperature (Tg) with reciprocal molecular weight of T-P34HB.	59
Figure 4.31 DSC 2nd heating curves of various P34HB/PLA blends prepared by solution blending using chloroform. The heating rate was 10 oC/min under N2.	60
Figure 4.32 DSC 2nd heating curves of various T-P34HB/PLA blends prepared by solution blending using chloroform. The heating rate was 10 oC/min under N2.	61
Figure 4.33不同組成的T-P34HB/PLA摻合物的Tg變化	61
Figure 4.34 GPC curve of PLA prepared by melt-blending at 170 oC .	64
Figure 4.35 GPC curve of P34HB component in the m-P34HB/PLA (20/80) blends prepared by melt-blending at 170 oC .	65
Figure 4.36 GPC curve of PLA component in the m-P34HB/PLA (20/80) blends prepared by melt-blending at 170 oC.	65
Figure 4.37 DSC 1st heating curves of various m-P34HB/PLA blends prepared by melt-blending at 170 oC .	67
Figure 4.38 DSC 2nd heating curves of various m-P34HB/PLA blends prepared by melt-blending at 170 oC .	68
Figure 4.39 Thermal degradation curves of m-P34HB/PLA blends under N2. Residual weight-temperature curves.	70
Figure 4.40 Derivative of weight-loss curves of m-P34HB/PLA blends.	70
Figure 4.41 Initial modulus of m-P34HB/PLA blends prepared from melt blending at 170 oC.	73
Figure 4.42 Yield Strength of m-P34HB/PLA blends blends prepared from melt blending at 170 oC.	73
Figure 4.43 Break strength of m-P34HB/PLA blends prepared from melt blending at 170 oC.	74
Figure 4.44 Elongation at break of m-P34HB/PLA blends m-P34HB/PLA blends prepared from melt blending at 170 oC.	74
Figure 4.45 Tensile stress-strain curves of m-P34HB/PLA blends at different compositions prepared by melt-blending at 170 oC for 20 min.	75
Figure 4.46經拉力測試後之m-P34HB/PLA樣品(m-P34HB/PLA, A=0/100, B=5/95, C=10/90, D=15/85, E=20/80, F= 25/75)	75
Figure 4.47 Impact strength of m-P34HB/PLA blends	76
Figure 4.48 SEM pictures of cryo-fractured surface of the neat PLA	78
Figure 4.49 SEM pictures of cryo-fractured surface of the m-P34HB/PLA (05/95) blends	78
Figure 4.50 SEM pictures of cryo-fractured surface of the m-P34HB/PLA (10/90) blends	79
Figure 4.51 SEM pictures of cryo-fractured surface of the m-P34HB/PLA (15/85) blends	79
Figure 4.52 SEM pictures of cryo-fractured surface of the m-P34HB/PLA (20/80) blends	80
Figure 4.53 SEM pictures of tensile-fractured surface of the neat PLA	80
Figure 4.54 SEM pictures of tensile-fractured surface of the m-P34HB/PLA (05/95) blend	81
Figure 4.55 SEM pictures of tensile-fractured surface of the m-P34HB/PLA (10/90) blend	81
Figure 4.56 SEM pictures of tensile-fractured surface of the m-P34HB/PLA (15/85) blend	82
Figure 4.57 SEM pictures of tensile-fractured surface of the m-P34HB/PLA (20/80) blend	82
Figure 4. 58 SEM pictures of tensile-fractured surface of the m-P34HB/PLA (25/75) blend	83
Figure 4.59 SEM pictures of whitening-fractured surface of the m-P34HB/PLA (05/95) blend	83
Figure 4.60 SEM pictures of whitening-fractured surface of the m-P34HB/PLA (10/90) blend	84
Figure 4.61 SEM pictures of whitening-fractured surface of the m-P34HB/PLA (15/85) blend	84
Figure 4.62 SEM pictures of whitening-fractured surface of the m-P34HB/PLA (20/80) blend	85
Figure 4.63 FTIR spectra of PLA and P34HB	87
Figure 4.64 FTIR spectra of m-P34HB/PLA blends at different compositions prepared by melt-blending at 170 oC for 20 min.	87
Figure 4.65不同組成之m-P34HB/PLA薄膜的XRD圖	88
Figure 4.66 Storage modulus (E') curves of various m-P34HB/PLA blends prepared by melt-blending at 170 oC by using dynamic mechanical analysis (DMA)	90
Figure 4.67 Loss modulus(E') curves of various m-P34HB/PLA blends prepared by melt-blending at 170 oC by using dynamic mechanical analysis (DMA)	90
Figure 4.68 Tan δ curves of various m-P34HB/PLA blends prepared by melt-blending at 170 oC by using dynamic mechanical analysis (DMA)	91
Figure 4.69 PLA與P34HB薄膜加入proteinase K分解7天後之殘存重量	94
Figure 4.70 Residual weight of m-P34HB/PLA blends with different compositions after enzymatic degradation by protease k for 14 days.	94
Figure 4.71 Degradation rate of of m-P34HB/PLA blends with different compositions after enzymatic degradation by protease k for 14 days.	95
Figure 4.72 Residual weight percentage of PLA component in the m-P34HB/PLA blends after enzymatic degradation by protease k for 14 days.	95
Figure 4.73 Residual thickness of m-P34HB/PLA blends at different compositions after enzymatic degradation by protease k for 14 days.	96
Figure 4.74 PLA薄膜於蛋白酶k分解1天後之表面SEM圖	97
Figure 4.75 m-P34HB/PLA(10/90)薄膜於蛋白酶k分解1天後之表面SEM圖	97
Figure 4.76 m-P34HB/PLA(20/80)薄膜於蛋白酶k分解1天後之表面SEM圖	98
Figure 4.77 PLA薄膜於蛋白酶k分解3天後之表面SEM圖	98
Figure 4.78 m-P34HB/PLA(10/90)薄膜於蛋白酶k分解3天後之表面SEM圖	99
Figure 4.79 m-P34HB/PLA(20/80)薄膜於蛋白酶k分解3天後之表面SEM圖	99
Figure 4.80 PLA薄膜於蛋白酶k分解6天後之表面SEM圖	100
Figure 4.81 m-P34HB/PLA(10/90)薄膜於蛋白酶k分解6天後之表面SEM圖	100
Figure 4.82 m-P34HB/PLA(20/80)薄膜於蛋白酶k分解6天後之表面SEM圖	101
Figure 4.83 PLA薄膜於蛋白酶k分解9天後之表面SEM圖	101
Figure 4.84 m-P34HB/PLA(10/90)薄膜於蛋白酶k分解9天後之表面SEM圖	102
Figure 4.85 m-P34HB/PLA(20/80)薄膜於蛋白酶k分解9天後之表面SEM圖	102
Figure 4.86 PLA薄膜於蛋白酶k分解14天後之表面SEM圖	103
Figure 4.87 m-P34HB/PLA(10/90)薄膜於蛋白酶k分解14天之表面SEM圖	103
Figure 4.88 m-P34HB/PLA(20/80)薄膜於蛋白酶k分解14天之表面SEM圖	104
Figure 4.89不同比例的m-P34HB/PLA薄膜於蛋白酶k分解14天之表面SEM圖	104
Figure 4.90不同m-P34HB/PLA薄膜於蛋白酶k分解數天之表面SEM圖，倍率為1000x	105
Figure 4.91 PLA薄膜於蛋白酶k分解數天後之截面SEM圖	106
Figure 4.92 m-P34HB/PLA (10/90)薄膜於蛋白酶k分解數天後之截面SEM圖	107
Figure 4.93 m-P34HB/P34HB (20/80)薄膜於蛋白酶k分解數天後之截面SEM圖	108
Figure 4.94不同時間下的蛋白酶K分解PLA的DSC曲線(1st heating curves)	109
Figure 4.95不同時間下的蛋白酶K分解m-P34HB/PLA (10/90)的DSC	109
Figure 4.96不同時間下的蛋白酶K分解m-P34HB/PLA (20/80)的DSC	110
Figure 4.97不同m-P34HB/PLA薄膜於蛋白酶K分解14天之結晶度變化	110
Figure 4.98 PLA與P34HB薄膜加入lipase分解60天後之殘存重量	114
Figure 4.99 Residual weight of m-P34HB/PLA blends with different compositions after enzymatic degradation by lipase for 60 days.	114
Figure 4.100 Degradation rate of of m-P34HB/PLA blends with different compositions after enzymatic degradation by lipase for 60 days.	115
Figure 4.101 PLA薄膜於脂肪酶分解7天後之表面SEM圖	116
Figure 4.102 m-P34HB/PLA(10/90)薄膜於脂肪酶分解7天後之表面SEM圖	116
Figure 4.103 m-P34HB/PLA(20/80)薄膜於脂肪酶分解7天後之表面SEM圖	117
Figure 4.104 P34HB薄膜於脂肪酶分解7天後之表面SEM圖	117
Figure 4.105 PLA薄膜於脂肪酶分解15天後之表面SEM圖	118
Figure 4.106 m-P34HB/PLA(10/90)薄膜於脂肪酶分解15天後之表面SEM圖	118
Figure 4.107 m-P34HB/PLA(20/80)薄膜於脂肪酶分解15天後之表面SEM圖	119
Figure 4.108 P34HB薄膜於脂肪酶分解15天後之表面SEM圖	119
Figure 4.109 PLA薄膜於脂肪酶分解30天後之表面SEM圖	120
Figure 4.110 m-P34HB/PLA(10/90)薄膜於脂肪酶分解30天後之表面SEM圖	120
Figure 4.111 m-P34HB/PLA(20/80)薄膜於脂肪酶分解30天後之表面SEM圖	121
Figure 4.112 P34HB薄膜於脂肪酶分解30天後之表面SEM圖	121
Figure 4.113 PLA薄膜於脂肪酶分解45天後之表面SEM圖	122
Figure 4.114 m-P34HB/PLA(10/90)薄膜於脂肪酶分解45天後之表面SEM圖	122
Figure 4.115 m-P34HB/PLA(20/80)薄膜於脂肪酶分解45天後之表面SEM圖	123
Figure 4.116 P34HB薄膜於脂肪酶分解45天後之表面SEM圖	123
Figure 4.117 PLA薄膜於脂肪酶分解60天後之表面SEM圖	124
Figure 4.118 m-P34HB/PLA(10/90)薄膜於脂肪酶分解60天後之表面SEM圖	124
Figure 4.119 m-P34HB/PLA(20/80)薄膜於脂肪酶分解60天後之表面SEM圖	125
Figure 4.120 P34HB薄膜於脂肪酶分解60天後之表面SEM圖	125
Figure 4.121 不同比例的m-P34HB/PLA薄膜於脂肪酶分解60天之表面SEM圖	126
Figure 4.122不同比例的m-P34HB/PLA薄膜於脂肪酶分解數天之表面SEM圖，倍率為1000x	126
Figure 4.123 PLA薄膜於脂肪酶分解數天後之截面SEM圖	127
Figure 4.124 m-P34HB/PLA薄膜於脂肪酶分解數天後之截面SEM圖	128
Figure 4.125 m-P34HB/PLA薄膜於脂肪酶分解數天後之截面SEM圖	129
Figure 4.126 P34HB薄膜於脂肪酶分解數天後之截面SEM圖	130
Appendix Figure 1 A-P34HB oligomer obtained by methanolysis (H2SO4/CH3OH=5/95, 50 mL) at 50 oC for 20 min.	144
Appendix Figure 2 A-P34HB oligomer obtained by methanolysis (H2SO4/CH3OH=5/95, 50 mL) at 50 oC for 40 min.	144
Appendix Figure 3 A-P34HB oligomer obtained by methanolysis (H2SO4/CH3OH=5/95, 50 mL) at 50 oC for 60 min.	145
Appendix Figure 4 A-P34HB oligomer obtained by methanolysis (H2SO4/CH3OH=5/95, 50 mL) at 50 oC for 80 min.	145
Appendix Figure 5 A-P34HB oligomer obtained by methanolysis (H2SO4/CH3OH=5/95, 50 mL) at 50 oC for 120 min.	146
Appendix Figure 6 A-P34HB oligomer obtained by methanolysis (H2SO4/CH3OH=5/95, 50 mL) at 60 oC for 20 min.	146
Appendix Figure 7 A-P34HB oligomer obtained by methanolysis (H2SO4/CH3OH=5/95, 50 mL) at 60 oC for 40 min.	147
Appendix Figure 8 A-P34HB oligomer obtained by methanolysis (H2SO4/CH3OH=5/95, 50 mL) at 60 oC for 60 min.	147
Appendix Figure 9 A-P34HB oligomer obtained by methanolysis (H2SO4/CH3OH=5/95, 50 mL) at 60 oC for 80 min.	148
Appendix Figure 10 A-P34HB oligomer obtained by methanolysis (H2SO4/CH3OH=5/95, 50 mL) at 60 oC for 120 min.	148
Appendix Figure 11 1st heating curves of various P34HB/CAB blends prepared by solution blending using chloroform. The heating rate was 10 oC/min under N2.	150
Appendix Figure 12 2nd heating curves of various P34HB/CAB blends prepared by solution blending using chloroform. The heating rate was 10 oC/min under N2.	150
Appendix Figure 13 1st heating curves of various P34HB/CAP blends prepared by solution blending using chloroform. The heating rate was 10 oC/min under N2.	152
Appendix Figure 14 2nd heating curves of various P34HB/CAP blends prepared by solution blending using chloroform. The heating rate was 10 oC/min under N2.	152
Appendix Figure 15不同製程之P34HB 第一次DSC升溫曲線	157
Appendix Figure 16不同製程之P34HB 第二次DSC升溫曲線	157
Appendix Figure 17 Linear plot of ln(DP) with reaction time according to the first-order degradation reaction of methanolysis at 40 °C. The complex rate constant obtained was 9.57×10-3 1/min.	160
Appendix Figure 18 Linear plot of ln(DP) with reaction time according to the first-order degradation reaction of methanolysis at 50 °C. The complex rate constant obtained was 8.75×10-3 1/min.	160
Appendix Figure 19 Linear plot of ln(DP) with reaction time according to the first-order degradation reaction of methanolysis at 60 °C. The complex rate constant obtained was 8.69×10-3 1/min.	161
Appendix Figure 20 Arrhenius plot of lnk vs. 1/T of methanolysis reaction of P34HB	161
Appendix Figure 21 Linear plot of 1/DP with reaction time according to the first-order degradation reaction of methanolysis at 40 °C. The complex rate constant obtained was 9.93×10-5 1/min.	164
Appendix Figure 22 Linear plot of 1/DP with reaction time according to the first-order degradation reaction of methanolysis at 50 °C. The complex rate constant obtained was 1.13×10-4 1/min.	164
Appendix Figure 23 Linear plot of 1/DP with reaction time according to the first-order degradation reaction of methanolysis at 60 °C. The complex rate constant obtained was 1.24×10-4 1/min.	165
Appendix Figure 24 Arrhenius plot of lnk vs. 1/T of methanolysis reaction of P34HB	165
 
表目錄
Table 4.1 Degree of polymerization (DP), number-average and weight-average molecular weight (Mn, Mw), and polydispersity index (PDI) of the P34HB oligomers obtained from the methanolysis of P34HB at 40°C.	38
Table 4.2 Degree of polymerization (DP), number-average and weight-average molecular weight (Mn, Mw), and polydispersity index (PDI) of the P34HB oligomers obtained from the methanolysis of P34HB at 50°C.	39
Table 4.3 Degree of polymerization (DP), number-average and weight-average molecular weight (Mn, Mw), and polydispersity index (PDI) of the P34HB oligomers obtained from the methanolysis of P34HB at 60°C.	39
Table 4.4 Rate constant (k) and DPo at different degradation temperatures in methanolysis along with the activation energy (Ea) and pre-exponet factor (A) obtained from Arrhenius plot.	47
Table 4.5 k, DPo, Ea, lnA and reaction temperature relationship	52
Table 4.6 Molecular weights of the P34HB oligomers obtained at various degradation times under thermal degradation temperature of 170 oC.	54
Table 4.7 Thermal transition properties of T-P34HB oligomers including glass transition temperature (Tg)、crystallization temperature (Tc)、and melting temperature (Tm) along with their molecular weight.	57
Table 4.8 Thermal transition properties of various T-P34HB/PLA blends prepared by solution blending using chloroform.Date were obtained from the 2nd heating curves.	62
Table 4.9 Molecular weight of m-P34HB/PLA blends determined by GPC	64
Table 4.10 Thermal transition properties of m-P34HB/PLA blends from the first heating curves. Sample were prepared by melt-blending at 170 oC.	67
Table 4.11 Thermal transition properties of m-P34HB/PLA blends from the second heating curves. Sample were prepared by melt-blending at 170 oC.	68
Table 4.12 Thermal degradation temperatures and char yield of m-P34HB/PLA blends.	71
Table 4.13 Tensile mechanical properties of m-P34HB/PLA blends at different compositions prepared by melt-blending at 170 oC for 20 min.	76
Table 4.14 Glass transition temperature of the m-P34HB/PLA blends obtained from the loss modulus and tan δ curves. Sample were prepared by melt-blending at 170 oC.	91
Table 4.15 Thermal transition properties of m-P34HB/PLA blends degraded by Proteinase k (1st heating)	111
Table 4.16 Molecular weights of m-P34HB/PLA blends obtained at various degradation times by Proteinase k.	112
Appendix Table 1 glass transition temperature (Tg) of various P34HB/CAB blends prepared by solution blending using chloroform.Date were obtained from the 1st heating curves.	151
Appendix Table 2 glass transition temperature (Tg) of various P34HB/CAB blends prepared by solution blending using chloroform.Date were obtained from the 2nd heating curves.	151
Appendix Table 3 glass transition temperature (Tg) of various P34HB/CAP blends prepared by solution blending using chloroform.Date were obtained from the 1st heating curves.	153
Appendix Table 4 glass transition temperature (Tg) of various P34HB/CAP blends prepared by solution blending using chloroform.Date were obtained from the 2nd heating curves.	153
Appendix Table 5 Different ratios of 3HB and 4HB thermal conversion characteristics -1	154
Appendix Table 6 Different ratios of 3HB and 4HB thermal conversion characteristics -2	155
Appendix Table 7 Different ratios of 3HB and 4HB thermal conversion characteristics -3	156
Appendix Table 8 不同製程1st的P34HB熱轉移性質	158
Appendix Table 9 不同製程2nd的P34HB熱轉移性質	158
Appendix Table 10 Rate constant (k) and DPo at different degradation temperatures in methanolysis along with the activation energy (Ea) and pre-exponet factor (A) obtained from Arrhenius plot.	162
Appendix Table 11Rate constant (k) and DPo at different degradation temperatures in methanolysis along with the activation energy (Ea) and pre-exponet factor (A) obtained from Arrhenius plot.	166

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