臺灣博碩士論文加值系統

由於聚乳酸塑膠同時擁有生物相容性與生物可分解性，且具有良好的機械特性，因此在所有的可分解性塑膠中佔有相當大的應用市場，如包裝材料、生醫材料及纖維材料等。
目前在食品或是醫療器材等均逐漸利用γ-射線來達到滅菌的效果，本研究針對市售聚乳酸材料在γ-射線照射前後，將聚乳酸材料在溫度120℃的條件下annealing 處理2小時，探討不同輻射劑量γ-射線對市售聚乳酸材料微結構與特性的影響。
由實驗結果得知，聚乳酸材料在抗拉強度、起始熱裂解溫度，均隨著輻射劑量的增加而衰退，且先經annealing處理之聚乳酸，較先照射γ-射線後再annealing處理之性質佳。
利用DSC分析熔點與結晶度的變化，發現隨著照射劑量的增加，呈現微幅上升後在再下降的趨勢，且先照射γ-射線後再annealing處理的樣品結晶度較高。而量測聚乳酸的平均分子量發現，呈現兩段不同衰退速率，在低照射劑量範圍衰退速率較大。
以XRD觀察結果顯示，聚乳酸試片的特性峰值並未因不同的輻射劑量而有明顯的改變。而將未經annealing處理的聚乳酸樣品，以每10℃的間隔由40℃逐步加熱120℃，每一個間隔持溫10分鐘，對聚乳酸進行即時XRD觀測（in situ XRD），發現未照射γ-射線的樣品在90℃時有繞射峰產生，而照射劑量為300kGy的試片，在60℃時即有明顯的繞射峰產生。

Polylactic acid (PLA), a well-known biodegradable and biocompatible polymer, contain excellent mechanical and thermal properties. Among these biodegradable polymers, PLA provides a possible candidate to replace the traditional plastics in the applications of packaging materials, bio-materials and fibers.
Different procedures can be utilized for the sterilization of the food and medical instruments. Gamma irradiation used for sterilization has performed excellent penertration characteristics of ionizing radiation and high efficient sterilization. The purpose of this study is to examine the effect of dose for gamma radiation on the microstructure and properties of PLA.
The glass transition, melting temperatures and molecular weight decreased with increasing irradiation dose. The mechanical property and thermal stability for PLA thermally treated before irradiation are higher than those treated after irradiation or without annealing treatment. The in situ X-ray diffraction studies have shown that the treatment of gamma irradiation decreases the recrystallization temperature.

摘要......................................................i
目次................................................... iii
表目錄.................................................. iv
圖目錄....................................................v
第一章 緒論.............................................1
1-1 研究背景.........................................1
1-2 研究目的.........................................3
第二章 文獻回顧與理論基礎.................................4
2-1 聚乳酸...........................................4
2-2 伽瑪射線之原理與應用............................15
第三章 實驗方法..........................................23
3-1 實驗藥品........................................23
3-2 實驗儀器........................................23
3-3 實驗步驟........................................24
3-4 實驗流程........................................28
第四章 結果與討論........................................29
4-1 機械性質探討....................................29
4-2 γ射線對分子量影響探討...........................37
4-3 熱性質分析......................................42
4-4 X-ray繞射分析...................................56
第五章 結論..............................................60
參考文獻.................................................62

1. Borden M.; Attawia M.; Laurencin C. T.; Biomaterials (2003)Vol.24 P597~609.
2. Langer R.; Vacant P.; Science(1993)Vol. 260 P920~926.
3. Jacobsen S.; Fritz H. G.; Polymer Engineering and Science (1999) Vol. 39 P1311~1319.
4.Pluta M.; Galeski A.; Journal of Applied Polymer Science (2002)Vol. 86 P1386
5.Gross V.; Cai H.; Journal of Applied Polymer Science (1996) Vol. 40 P2701.
6.陳家杰；輻射在食品保存之應用。食品工業，2001,33(2)：11-16。
7.陳美瑩；照射技術及其在食品中之應用。食品工業， 2003a, 35(11)：47-60。
8.連佩盈；自加馬射線照射之靈芝殘渣製備鹼多醣及其抗氧化與理化性質；國立中興大學食品暨應用生物科技學系碩士論文。2006。
9.陳琤琤；輻射照射，保護環境。核能天地，1992, 9:48-49。
10.李星等；輻射技術在高分子材料中的應用。雲南化工，2002, 29 (2)
11.中華民國環保生物可分解材料協會季刊;2002年1月。
12. Holten CH, Müller A, Rehbinder D. Lactic acid: properties and chemistry of lactic acid derivatives. Weinheim: Verlag Chemie, (1971).
13. Turnbull D.;Fisher J. C.; Chem J. Phys., (1949) Vol. 17 P71
14. Lunt J.; Polymer Degradation and Stability, (1998) Vol. 59 P145~152
15. Carothers WH, Dorough GL, van Natta FJ. Studies of polymerization and ring formation. X. The reversible polymerization of six-membered cyclic esters. J Am Chen Soc (1932)54:761-72.
16. 徐世昌，化工資訊(2001)Vol. 2 P36~45
17. Vink E. T. H.; Rabago K. R.; Glassner D.A.; Gruber P. R.; Polymer Degradation and Stability, (2003) Vol. 80 P403~419
18. Anders Södergard.; Mikael Stolt.; Progress In Polymer Science,(2002)Vol. 27 P1123~1163
19. Hollinger J. O.; Battistone G. C.; Biodegradable bone repair materials, Synthetic polymers and ceramics Clinical Orthopaedics & Related Research,(1986) Vol. 207 P290~305
20.Kulkarni R.K.; Pani K.C.; Neuman C.; Leonard F.; Polylactic acid for surgical implants. Arch Surg(1966) Vol. 93 P839~843
21.Grizzi I.; Garreau H.; Li S.; Vert M.; Biomaterials (1995)Vol. 16 P305~311
22.Vert Michel; Suming Li; Girod-Holland Sophie; Journal Controlled Release(1996)Vol.40 P41~53
23.Stephen McCarthy; Suming Li; Biomaterials(1999) Vol. 20 P35~44
24.Farnia S.M.F.; Mohammadi-Rovshandeh; Sarbolouki M.N.; Journal of Applied Polymer Science(1999)Vol.73 P633~637
25.Hideto Tsuji; Swapan Kumar Saha; Polymer Degradation and Stability(2006)Vol.91 P1665~1673
26.Tarantili P.A.; Andreopoulos A.G.; Proikakis C.S.; Polymer Degradation and Stability(2006)Vol.91 P614~619
27. Yiqi Yang; David Karst; Polymer(2006)Vol. 47 P4845~4850
28. Heller J.; Gurny R.; Merkli A.; Prog. Polym. Sci. (1998)Vol. 23 P563~580
29. Materin O.; Averous L.; Polymer(2001)Vol. 42 P6209
30. Ljungberg N.; Wesslen B.; Journal of Applied Polymer Science(2002)Vol. 86 P1227
31. C. Birkinshaw, M. Buggy, G. G. Henn; Polymer Degradation and Stability(1992)Vol.38 P249~253.
32. Pramono Nugroho; Hiroshi Mitomo; Fumio Yoshii; Tamikazu Kume; Polymer Degradation and Stability (2001)Vol. 72 337~343
33. D. Milicevic, S. Trifunovic, S. Galovic, E. Suljovrujic; Radiation Physics and Chemistry (2007) Vol. 76 1376-1380
34. Kai-Lai G. Ho, Anthony L. Pometto III, and Paul N. Hinz; Journal of Environmental Polymer Degradation, (1999) Vol. 7, No. 2
35. Mc Neill, I., Leiper, H.;Polym. Degrad. Stabil; (1985) Vol. 11, 309-321.
36. Miyata, T., Masuko, T.; Polymer(1998)Vol. 39, 5515-5521.