臺灣博碩士論文加值系統

聚羥基烷酸酯 (polyhydroxyalkanoates，PHAs)，是一種生物可分解性塑膠，在特定溫度下，可被微生物分解成水及二氧化碳。因其無毒且可以藉由改變連接側鏈而具有不同的性質，極具發展潛力。在使用微生物醱酵生產PHAs，因PHAs為菌體內產物，須經過分離純化過程來取得產品。在分離過程加熱與乾燥程序將會影響PHAs的分子量而改變其性質，因此，本研究目的在探討菌產PHAs在分離過程中以加熱進行有機溶劑溶解對PHAs性質的影響，在本研究採用聚羥基烷酸酯即聚羥基丁酸酯 (polyhydroxybutyrate ，P3HB) ，探討變因包含溶劑的溶解度，溫度、溶解時間、分子量及結晶度等。
聚羥基烷酸酯在溶液中的量以氣相層析儀（Gas Chromatography, GC）和乾燥重量作為定量，分子量由膠體滲透層析儀（Gel Permeation Chromatography, GPC）測得相對分子量。使用有機溶劑包含氯仿、二甲苯、碳酸丙烯酯等，利用溶劑溶解P3HB和P3HBV，溶解溫度升高將會增加分子量的降解，相對也提升了溶解量。如氯仿在70 oC加熱一小時可溶量達 0.03 g/mL，其分子量下降5 %，；二甲苯在100 oC加熱一小時可溶量達0.05 g/mL，惟其分子量下降由0.25 % ～ 0.70 %，在溫度達100 oC後分子量即降解。以120 oC為例，加熱半小時後，則降解29 %，其降解速率為58 %/h。
在100 oC等溫溶解條件下，加熱一小時內，溶劑：二甲苯、環已酮、稀釋劑150之溶解量為 0.052 g/mL、 0.006 g/mL及0.005 g/mL。結晶度為43.5%，活化能為0.39 kJ/mol。





關鍵詞：聚羥基烷酸酯，聚羥基丁酸酯，溶解度，純化

PHAs are one kind of biodegradable plastic. It can be decomposed to water and carbon dioxide by microorganism at room temperature in nature. Because of monomer, PHAs has been found over 150 kinds of structures. That also means that it has more widely range in industry process and application. Because PHAs were produced with fermentation by microorganism, it must be purification to get purity product. That is why PHAs price is always higher than tradition oil plastic. But when PHAs was purify, heating and drying process will change its property. This study discusses molecular weight degradation of baterial PHAs in purification process. P3HB was used in experimental. Solubility, temperature, dissolve time, molecular weight and crystallization will be discussed.
The concentration analysis for PHAs is used gas chromatographic (GC) and acidic methanolysis. Using acidic methanolysis with 3 % H2SO4 and heating in 100 oC oven for 6 h. The molecular weight analysis for PHAs is used GPC. When temperature increases, P3HB molecular weight decrease rate will increase so that also increases solubility. For example, chloroform’s solubility of P3HB can reach 0.03 g/mL after heating 1 h at 70 oC and molecular weight decrease from 0.5 %. Xylene’s solubility of P3HB can reach 0.05 g/mL after heating 1 h at 100 oC and molecular weight decrease from 0.25 % to 0.70 %. When heating temperature over 100 oC, molecular weight decreasing rate will increase very fast. For example, P3HB molecular weight decrease 29 % after heating 0.5 h at 120 oC, decrease rate is 58 %/h.








Keywords: polyhydroxyalkanoates, polyhydroxybutyrate, solubility, purification

摘要 I
Abstract II
致謝 III
Contents IV
List of Tables VII
List of Figures VIII
Notations X
Chapter 1 Introduction 1
1.1 Introduction 1
1.2 Introduction to biodegradable plastics 4
1.2.1 Biodegradable plastics 5
(I) Polyester 5
(II) Polyalcohol 6
1.2-2 Photodegradable plastic 7
1.2-3 Disintegradable plastic 8
1.3 Economic impacts of biopolymers 9
1.4 Polyhydroxyalkanoates 11
1.4-1 Polyhydroxybutyrate (P3HB) 12
1.4-2 Poly (3-Hydroxybutyrate-co-3-Hydroxyvalerate) (P3HBV) 14
1.5 Production of PHAs by microorganisms 14
1.5-1 Fatty acid β oxidation pathway 14
1.5-2 Acetyl coenzyme A pathway 15
1.5-3 Fatty acid synthesis pathway 15
1.6 Degradation of PHAs 22
1.7 Comparison PHAs and PLA 23
1.8 The products of biodegradable materials 24
1.9 Cost evaluation 24
1.10 Physical properties 26
1.11 National regulation for biodegradable plastics 26
1.12 Purification strategy of PHAs 27
1.12-1 Solvent extraction 27
1.12-2 Digestion methods 28
1.12-3 Mechanical disruption 29
1.13 Motivation and objective 33
1.14 Experimental design 34
Chapter 2 Materials and Method 35
2.1 Solvents 35
2.2 Equipment 36
2.3 Materials 36
2.4 Pretreatment of P3HB raw material 37
2.5 Solubility Measurement of P3HB 37
2.6 Molecular weight measurement of P3HB 38
2.7 Determination concentration of PHAs 39
(I) Spectrophotometer 39
(II) Gas chromatography 39
2.7-1 Pre-treatment by acidic methanolysis for P3HB analysis 40
2.7-2 GC calibration curve 42
2.8 Degradation of P3HB 43
2.9 Determination of crystallinity 43
2-10 UV absorbance 43
Chapter 3 Results and Discussion 46
3.1 Effect of agitation 46
3.2 Effect of solvent 47
3.3 Effect of temperature 57
3.4 Effect of Molecular weight 58
3.5 Effect of crystallization 58
Chapter 4 Conclusions and Future work 63
4.1 Conclusions 63
4.2 Future work 63
Reference 64
Curriculum Vitae 70
Appendix A 72
A-1 Hydrocarbons solvents 72
A-1.1 Toluene 72
A-1.2 Xylene 72
A-1.3 Cyclohexanone 73
A-1.4 n-Hexadecane 73
A-2 Halogenated solvents 73
A-2.1 Chloroform 73
A-3 Esters solvents 74
A-3.1 Ethyl acetate 74
A-3.2 Butyl acetate 74
A-3.3 Propylene carbonate 74
A-4 Alcohols solvents 74
A-4.1 1-Pentanol 74
A-5 Ethers solvents 75
A-5.1 Tetrahydrofuran (THF) 75
A-5.2 Anisole 75
A-6 Others solvents 75
A-6.1 Solvesso 150 75
A-6.2 Thinner 170 76
A-6.3 1-Methyl-2-pyrrolidinone (NMP) 76

Abdorreza, M.N., M. Robal, L.H. Cheng, A.Y. Tajul, A.A. Karim, Physicochemical, thermal, and rheological properties of acid-hydrolyzed sago (Metroxylon sagu) starch, LWT - Food Science and Technology, 46, 135-141 (2012).
Achilias, D.S., E. Panayotidou, I. Zuburtikudis, Thermal degradation kinetics and isoconversional analysis of biodegradable poly(3-hydroxybutyrate)/organomodified montmorillonite nanocomposites, Thermochimica Acta, 514, 58-66 (2011).
Adamus, G., W. Sikorska, H. Janeczek, M. Kwiecien, M. Sobota, M. Kowalczuk, Novel block copolymers of atactic P3HB with natural PHA for cardiovascular engineering: Synthesis and characterization, European Polymer Journal, 48, 621-631 (2012).
Anderson, A.J., D.R. Williams, E.A. Dawes, D.F. Ewing, Biosynthesis of poly(3- hydroxybutyrate-co-3-hydroxyvalerate) in rhodococcus ruber, Canadian Journal of Microbiology, 41, 1, 4-13 (1995).
Anderson AJ, EA. Dawes, occurrence, metabolism, metabolic role, and industrial uses of bacterial polyhydroxyalkanoates, Microbiol Review, 54, 450-472 (1990).
Avella, M., E. Martuscelli, M. Raimo, Properties of blends and composites based on poly(3-hydroxy)butyrate (P3HB) and poly(3-hydroxybutyrate-hydroxyvalerate) (P3HBV) copolymers, Journal of materials science, 35, 523-545 (2000).
Baptist, J.N., Process for preparing poly-β-hydroxybutyric acid, United States Patent, 3, 044, 942 (1962).
Barham, P.J., A Feller, EL Otun, PA Holmes, Crystallization and morphology of a bacterial thermoplastic: poly-3-hydroxybutyrate. Journal of Materials Science, 19, 2781-2794 (1984).
Barham, P.J., Physical properties of poly(hydroxybutyrate) and poly(hydroxybutyrate- co-hydroxyvalerate), Novel Biodegradable Microbial Polymer, 81 (1990).
Burger, H.M., H.M. Muller, D. Seebacw, Matrix- assisted laser desorption and ionization as a mass spectrometric tool for the analysis` of poly[(R)-3-hydroxybutanoates] comparison with gel permeation chromatography, Macromolecules, 26, 4783-4790 (1993).
Byrom, D., Polyhydroxyalkanoates, Plastics from microbes: Microbial synthesis of polymers and polymer precursors, 5 (1994).
Calvao, P.S., J.M. Chenal, C. Gauthier, N.R. Demarquette, A. Bogner, J.Y. Cavaille, Understanding the mechanical and biodegradation behaviour of poly(hydroxybutyrate) /rubber blends in relation to theirmorphology, Society of Chemical Industry (2011).
Charron, N., Plastic Products and Industries, Statistics Canada Reference, 33-250-XIE, Ottawa, Canada: Manufacturing, Construction, and Energy Division (2001).
Chen, G..Q., Plastics completely synthesized by bacteria: polyhydroxyalkanoates (2010).
Chokradjaroen, C., X. Li, K. Tamura, Mutual solubility measurements and correlations of imidazolium-based ionic liquid mixtures with alcohols, J. Chem. Thermodynamics, 46, 72–79 (2012).