本研究主要以溶膠-凝膠法製備矽膠/有機高分子混成材料。這些混成材料經由配方組成調配及製程條件控制，不僅在性能上結合有機材料的韌性及無機材料的剛性與耐熱性，亦可因有機及無機材料之官能基設計，使具有獨特之光的、電的、磁的性質或其它的機能性。研究中分別合成三種混成材料：透明性之矽膠/聚(羥乙基)甲基丙烯酸乙酯[Silica/ poly(2-hydroxyethyl methacrylate); PHEMA] 混成體, 具生物活性之(3-trimethoxysilyl)propyl methacrylate (MSMA)/HEMA 混成聚合體和具pH敏感性之矽膠/幾丁聚醣(Silica/Chitosan)混成水膠。

一、 透明性Silica/PHEMA混成材料

採用不同的方法合成Silica/PHEMA混成材料：tetramethoxysilane (TMOS)　和2-hyrdoxylethyl methacrylate (HEMA)混合溶液在酸或鹼催化及有、無添加共溶劑甲醇條件下，經溶膠-凝膠及原位(In Situ)聚合反應形成Silica/PHEMA混成體（TMOS/HEMA）; PHEMA高分子直接和凝膠態矽膠溶膠(Colloidal silica sol)，以甲醇作為共溶劑，進行物理性摻合(Colloidal silica/PHEMA); PHEMA高分子與無機前驅物(TEOS)混合，以甲醇作為共溶劑，在酸催化下進行溶膠-凝膠反應(TEOS/PHEMA)。
加入甲醇於TMOS/HEMA溶膠液中，會增加矽醇之酯化(Esterification)和解聚(Depolymerization)反應，加上矽醇濃度被稀釋，使溶膠-凝膠聚合反應速率減緩，生成的矽膠粒徑較小，特別是在酸催化下，合成之矽膠粒子其粒徑小於40 nm。FT-IR圖譜鑑定下證實合成之TMOS/HEMA混成膠體，在DSC圖中出現之放熱峯為凝膠態矽膠和PHEMA高分子鏈在高溫下產生化學共價鍵結合。因此，在鹼催化下所製得之TMOS/HEMA混成膠體在600°C下，殘餘重量大於初始TMOS添加入溶膠液的量。
Colloidal　silica/PHEMA混成體中奈米級矽膠粒子均勻分散於PHEMA高分子相內，其界面間連結機制以Van der waals力和微弱之分子間氫鍵作用力為主。TEOS/PHEMA混成體中，PHEMA高分子鏈纏繞於奈米級之矽膠網狀結構内形成類似半互相貫穿網狀結構（Semi-IPN）而達到分子層級混成，矽膠與PHEMA連結機制主要以分子間和分子內氫鍵鍵結。因此，TEOS/PHEMA混成體比Colloidal　silica/PHEMA混成體具有較佳之表面平滑性、高透明性及較優之熱穩定性。

二、具生物活性之MSMA/HEMA 混成聚合體之合成

將MSMA和HEMA兩種單體，分別以莫耳比為0.05/0.095 至　0.2/0.8之不同比例混合，經由自由基聚合和溶膠-凝膠反應，合成MSMA/HEMA混成體。　當具有反應性C=C之兩混成單體進行自由基共聚合時，在MSMA中之矽氧烷基亦同時產生水解-縮合反應而形成奈米級矽膠體纏繞於MSMA /HEMA　共聚合體鏈中之混成結構。在混成溶膠液中，加入氯化鈣鹽後，產生ºSi-O-和鈣離子結合之錯合體。將此含有鈣離子之混成體浸泡於模擬生物體液中(Kokubo 緩衝溶液)一星期，發現混成體表面長出含有類似骨頭成分之氫氧基磷灰石([Ca10(PO4)6(OH)2]；Hydroxyapaite；HA)晶體，其中，以MSMA/HEMA莫耳比0.1/0.9及0.15/0.85所製成的混成體，可生成較為穩定及較多量之HA晶體。在Kokubo 緩衝溶液中，MSMA/HEMA　混成體的表面形成HA結晶機制是因為混成體中之Si-OH基幫助鈣離子之釋放，並有效催化HA晶體成核成長。

三、具pH敏感性之矽膠/幾丁聚醣(Silica/Chitosan)混成水膠

將TMOS和Chitosan，分別以重量比為2/8 至6/4之各種比例混合，經由溶膠-凝膠反應，合成矽膠/幾丁聚醣混成體，而形成幾丁聚醣高分子鏈糾纏於矽膠網狀中之結構。矽膠/幾丁聚醣混成體呈現比純幾丁聚醣更好之吸水性。添加30 wt% TMOS之矽膠/幾丁聚醣混成體，其飽合吸附之水含量較幾丁聚醣高約一倍以上。矽膠/幾丁聚醣混成體交互置換在pH 2.2檸檬酸溶液與pH7.4之檸檬酸/磷酸氫鈉緩衝溶液中，可展現膨潤-去膨潤可逆應答特性，顯示此混成體具有極佳的pH敏感性水膠行為。

The merits to hybridize the inorganic material with the organic polymer including to reduce the brittleness of inorganic material, to enhance the rigidity and thermal resistance of organic material and to provide unique properties such as in optical, in electronic, in magnetic or others by the proper design and selection of organic and inorganic precursors to hybridize, hence, was the intention to study in this thesis. Three types of silica/polymers hybrid materials, silica/poly(2-hydroxyethyl methacrylate (PHEMA) hybrids, bioactive (3-trimethoxysilyl)propyl methacrylate (MSMA)/HEMA hybrid and pH- sensitive silica/chitosan hydrogel were synthesis through the sol-gel process.

System I. Transparent silica/PHEMA hybrid materials

The silica/PHEMA hybrids were synthesized by various ways: the tetramethoxysilane (TMOS)/2-hyrdoxylethyl methacrylate (HEMA) hybrid gels were synthesized with acid and base catalysts, via the in situ polymerization of HEMA, with and without co-solvent methanol (TMOS/HEMA); the direct mixing of colloidal silica with PHEMA using methanol as a co-solvent (colloidal silica/PHEMA); and the adding of the inorganic precursor, tetraethyloxysilane (TEOS), to the PHEMA/methanol solution, followed by the sol-gel process with an acid-catalyst (TEOS/PHEMA).
With methanol in the TMOS/HEMA sol, the enhanced esterification and depolymerization reactions of the silanols resulted in a slower growth of silica particles. The silica particles that were synthesized with an acid catalyst were less than 40 nm. The thermal resistance of PHEMA chains was enhanced by the addition of colloidal silica. The Fourier transform infrared characterizations and the exothermal peaks on the differential scanning calorimetry traces of these hybrid gels indicated chemical hybridization occurring as a result of condensation of the colloid silica and PHEMA at higher temperatures. Hence, the residual weight content of TMOS in the synthesis with the base catalyst was even higher than the content of TMOS in the hybrid sol.
The structure of the colloidal silica/PHEMA hybrid consisted of nano-silica uniformly dispersed in the PHEMA phase with slight inter-molecular hydrogen bonding. The structure of TEOS/PHEMA hybrid was similar to a semi-interpenetrated polymer network (semi-IPN) with PHEMA chains tethered into the nano-silica network by inter- and intra-molecular hydrogen bonding. Consequently, the TEOS/PHEMA hybrid gels exhibited a smoother surface, higher transparency, and better thermal stability than the colloidal silica/PHEMA hybrid gels.

System II. Bioactive MSMA/HEMA hybrid materials

The MSMA and HEMA monomers were mixed with the molar ratio ranged from 0.05/0.95 to 0.2/0.8, and then hybridized through the free-radical polymerization. Both monomers contained reactive C=C bonds accompanied with the hydrolysis and condensation reactions of trimethoxysilane groups in MSMA resulted in the structure of MSMA/HEMA hybrid as that copolymer chains tethered with nano-silica particles. During the synthesis period, a calcium salt was added into the MSMA/HEMA hybrid sol; therefore, a complex pair of calcium ion and Si-O- was formed and tethered to the copolymer chains. The hybrid gel with calcium ion tethered was immersed in the Kokubo buffer solution for one week, a bone-like hydroxyapatite (HA) layer was found on the surface of hybrid gel and the hybrids with the molar ratios of MSMA/HEMA being 0.1/0.9 and 0.15/0.85 exhibited more stable and larger HA crystals on their surfaces than others. This result indicated that the MSMA/HEMA hybrid was a bioactive material. The mechanism to form HA crystal on the surface of MSMA/HEMA hybrid in the Kukobo solution was due to that the HA nucleation triggered by a catalytic effect of silanol (Si-OH) group and accelerated by the release of calcium ion (Ca2+) from the hybrid material into the solution.

System III. pH-sensitive silica/chitosan hybrid materials

The TMOS sol and chitosan were mixed with the weight ratio ranged from 2/8 to 6/4, and then hybridized through the sol-gel process. The structure of hybrid was that the chitosan chains extended into the nano-scale silica network. The synthesized hybrid hydrogel exhibited better water uptake content than the pure chitosan, The equilibrium water content of the silica/chitosan hybrid, synthesized from TMOS/chitosan mixture with the weight ratio of 3/7, was double than the pure chitosan. In addition, the hybrid hydrogels showed a reversible swelling and de-swelling behaviors while alternatively placed in the pH 2.2 citric acid solutions and pH 7.4 citric acid/NaHPO4 buffer solutions. This result demonstrated that the TMOS/chitosan hybrids exhibited an excellent pH-sensitive hydrogel behavior.

參考文獻

1. M. Ebelmen, Ann.chem. phys., 16, 129, 1846.
2. G. Blough, M. G. Morris, Science, 276, 923, 1997.
3. K.Goto, J. Appl. phys., 37, 2274, 1998.
4. M. Canva, P. Georges, A. Brun, J. Non. Crys. Sol., 147, 636,1992.
5. G. H. Hsiue, R. J. Jeng, Polymer Prep., 39, 1032, 1998.
6. J. M. Jordan, J. Phys. Colloid Chem., 53, 245, 1950.
7. L.H. Sperling, Interpenetrating Polymer Networks and Related Materials, Plenum, New York, 1981.
8. K. Liand, T.A. King, J. Sol-Gel Sci. Tech., 4, 75, 1995.
9. S. A. Srinijasan et al., Polymer, 39, 2415,1998.
10 . H. Schmidt, B. Seiferling, G. Philipp , In Ultrastructure Processing of
Advanced Ceramics, J. D. Mackenzia, et al. Eds., Wiley, New York, p651, 1988.
11. H. Schmidt, Ultratructure Processing of Advanced Materials,
, L. L. Hench, Eds., Wiley: New York, p409,1992.
12. J. Avnir et al., Mater. Lett., 6, 1605, 1994.
13. G. Braun et al., Mater. Chem. 6,1605,1990.
14. J. Wen et al., Chem. Mater., 8, 1667, 1996.
15. C. D. Feng, et al., Sensors & Actuators, 40, 217, 1997.
16. C. Ohtsuki, T. Miyazaki, M. Kyomoto, M. Tanihara, A. Osaka, J. Mater. Sci. Mater. Med., 12, 895, 2001.
17. K. Merrett , C.M. Griffith , Y. Deslandes , G. Pleizier , M.A. Dubé , H. Sheardown, J. Biomed Mater. Res., 67A, 98, 2003.
18. J. Zarzycki, et al., J. Sol-Gel Sci. Tech., 8,17, 1997.
19. R. Reisfeld, C. K. Jorgensen, Chemistry Spectroscopy and Applications of Sol-Gel Glasses, Springer-Verlag, Berlin, 1992.
20. B. Jirensons et al., Colloid chemistry, Wiley, New York, 1962.
21. R.K.Iler，The Chemistry of Silica，Wiley，New York,1979.
22. D.C. Bradely et al., Mater. Alkoxides Academic: London, 1987.
23. H. D. Cogan et al., Chem. and Eng. News, 24, 2499, 1946.
24. C. Sanchez, F. Ribot, J. Chem., 18, 1007, 1994.
25. J. Wen, G. L. Wilkes, Chem. Mater., 8, 1667, 1996.
26. H. Schmidt, B. Seiferling, Mater. Res. Soc. Symp. Proc, 73, 739, 1986.
27. C. S. Parkhurst, L. A. Doyle, L. A. Silverman, S. Singh, M. P. Anderson, D. McClurg, G. E. Wnek, and D. R. Uhlmann, Mater. Res. Soc. Symp. Proc., 73, 769, 1986.
28. B. E. Yoldas, J. Am. Ceram. Soc., 65, 388 , 1982.
29. B. E. Yoldas, J. Non-cyst. Solids, 51, 105, 1982.
30. A. M. Gadalla and M. Greenblant, J. Non-cryst. Solids. 143, 1 , 1992.
31. A.M.Gadalla and S.J.Yun,J.Non-cryst.Soilds. 143, 121,1992.
32. R.A. Assink and B.D. Kay, J. Non-Cryst. Solids, 99, 359, 1998.
33. E. J. A. Pope, J. D. Mackenzie, J. Non-Cryst. Solids, 87, 185, 1986.
34. D. R. UIruich, et al., J. Non-cryst. Solids. 100, 1744, 1988.
35. K. D. Keefer, The Effect of Hydrolysis Condition on the Structure and Growth of Silicate Polymers, MRS 1984 Spring Meeting, Feb. 27-29 Albaguerque, New Mexico
36. R. E. Timms, et al., J. Chem. Soc., A. 69, 1974.
37. R. K. Iler, The chemistry of silica, Wiley-inter Science, 1979.
38. Z. Z. Vysotskii et al., Adsorption and Adsorbents, Wiley, New York,1973.
39. C. J. Brinker, J. Non-Cryst. Solids, 100 , 30, 1988.
40. E.R. Pohl and F.D. Osterholtz, in Molecular Characterization of Composite Interfaces,Eds. H. Ishida, G. Kumar, Plenum, New York, p. 157, 1985.
41. D. R. Uhlman, B.J. J. Zeiinski and G. E. Wenk," in Better Ceramics Through Chemistry", Eds. C. J. Brniker, D.E. dark and D. R. Ulrich (Elsevier Science Publishing Co. lnc.),59, 1984.
42. C. J. Brinker, R. Sehgal, S. L. Hietala, R.Deshpande, D. M. Smith, D. Loy and C. S. Ashley, J. Membr. Sci., 94, 102, 1994.
43. C. J. Brinker, R. Sehgal, S. L. Hietala, R. Deshpande, D. M. Smith, D. Loy and C. S. Ashley, J. Membr. Sci., 94, 85, 1994.
44. W. Colby et al., J. Non-Cryst. Solids, 99, 129, 1988.
45. B. B. Lakshmi, P. K. Dorhout, Chem.Mater., 9, 857, 1997.
46.J. C. Hulteen,V. P. Menon , J. Chem. Soc., 92, 29,1996.
47. H. Xu, S. W. Kuo, F. C. Chang, Polymer Bulletin, 48, 469, 2002.
48. H. T. Lin, E. Bescher, J. D. Mackenzie, H. Dai, O. M. Stafsudd, J. Mater. Sci., 27, 264, 1992.
49. E. J. A. Pope, A. Asami, J. D. Mackenzie, J. Mater. Res., 4, 1018,1989.
50. Y. Chujo, et al., Macromolecules, 26, 5681, 1993.
51. C. J. T. Landry, , B. K. Coltrain, B. K. Brady, Polymer, 33, 1486, 1992.
52. N. A. Peppas, R. Langer, Science, 263, 1715 1994.
53. R. Langer, L. G. Cima, J. A. Tamada, E. Wintermantel, Biomaterials, 11,739, 1990.
54. S. Choen, et al., Trans, Am. Soc. Artif. Intern. Organs, 37, 44, 1991.
55. J. A. Hubbel et al., Chem. Eng. News, 13, 42, 1995.
56. J. W. Boretos, et al., Eds., Contemporary Biomaterials, Noyes Publications, New Jersey, 1984.
57. 王盈錦，生物醫學材料, 合記圖書公司發行，pp255
58. J. B. Park, R. S. Lakers, Biomaterials：An Introduction，2nd eds., New York, 1992, P1enum Press.
59. J. Charnley: "Acrylic cement of orthopedic surgery", E.&S. Livingstone, London, 1970
60. L.L. Hench and E. C. Ethridge, Biomaterial, Academic Press. Inc., 1982.
61. T. Kokubo, S. Ito, Z. T. Huang, T. Hayashi, S. Sakka, T. Kitsugi, T.
Yammnuro, J. Biomed. Mater. Res. 24, 331, 1990.
62. J. T. Heikkila, A. J. Aho, Biomaterials, 17, 1755, 1996.
63. C. Ohtsuki, T Miyazaki, M. Kyomoto, M. Tanihara, A. Osaka, J. Mater. Sci.: Mater. Med. C22, 895, 2002.
64. W. Weng, J. L. Baptista, J. European Ceramic Science, 17, 1151, 1997.
65. 黃瑞祥, ‘氫氧基磷灰石陶瓷離子之機械性質與其粉末製備’, 義守大學碩士論文，2002.
66. H. Eerper, et al., Bioactive bone cements, Proc. Inst. Mech. Eng. Part , 65 113, 1998.
67. A.S. Posner, A. Perloff, and A.D. Diorio, Acta. Crystallogr., 11, 308, 1958.
68. O. Wichterle, D. Lim, Nature, 185, 117, 1960.
69. F. Lim, A.M. Sun, Science, 210, 908, 1980.
70. A. S. Hoffman, Advance Drug Delivery Review, 43, 3, 2002.
71. F. Lira, A. M. Sun, Science, 210, 908, 1990.
72. R. Dagani, et al., Chem. Eng. News, 75, 26, 1997.
73. H. Gin, B. Dupuy, A. Baquey, C. Baquey, D. Ducassou, Macromolecules, 32, 7370, 1999.
74. S. H. Gehrke, P. I. Lee, In Specialized Drug Delivery Systems 45, 333, 1990.
75. M. Irie, et al., Adv Polym. Sci., 94, 28, 1990.
76. W. E. Hennink, C. F. Nostrum, Adv. Drug Deliv. Rev. 54, 13, 2002.
77. Y. Qiuy, Advanced drug Delivery, 53, 321, 2001.
78. S. J. Kim, S. R. Sin, Biomaterials Polymer, 24, 2067, 2003
79. C. D. Diakoumakos, I. Raptis, Polymer, 44, 251, 2003.
80. K. Prashantha, K. Vasanth kumar pai, B. S. Sherigara, S. prasannak- umar, Bull. Mater. Sci.,. 24, 535, 2001.
81. 陳榮輝，金曉珍，水產甲殼廢棄物開發經濟價值之幾丁質，幾丁聚醣，幾丁寡醣研究之規劃報導，科學發展月刊，第二十三期，550, 1995.
82. 鄭俊楠, 台灣科技大學碩士論文，2001.
83. N. Manolova, I. Rnahkov, J. Bioact Comp. Polymer, 10, 285, 1995.
84. K. Kurita, K. Tomita, S. Ishii, S. Nishimura, K. Shimoda, J. Polym. Sci., Part A: Polym. Chem. 31, 2393, 1993.
85. M. Yalpani, F. Johnson, L.E. Robinson, Chitin, Chitosan: Sources, Chemistry, Biochemistry, Physical Properties and Applications, Elsevier, Amsterdam, 1992.
86. M.N.V. Ravi Kumar, P. Singh, P.K. Dutta, Indian Drugs, 36, 393, 1999.
87. M.T. Qurashi, H. S. Blair, J. Appl. Polym. Sci., 46, 255, 1992.
88. K.D. Yao, T. Peng, M.F.A. Goosen, J.M. Min, Y.Y. He, J. Appl. Polym. Sci. 48, 343, 1993.
89. T. Peng, K.D. Yao, M.F.A. Goosen, J. Polym. Sci., Part A: Polym. Chem. 32, 66, 1994.
90. Lin, H.T.: Bescher, E: Mackenzie, J.D.: Dai, H: Stafsudd, O.M., J.Matl. Sci. 27, 264, 1992.
91. Levy, D.: Pena, J.M.S.: Serna, C.J.: Oton, J.M.; J. Non-Cryst. Solids, 147, 646, 1992.
92. Lin, H.T.: Bescher, E: Mackenzie, J.D.: Dai, H: Stafsudd, O.M.,J.Matl. Sci., 27, 264, 1992.
93. S. J. Gregg, et al., Adsorption, Surface Area, and Porosity (Academic Press London , 1967.
94. S. Brunauer, L.S. Deming, W.S. Doming, and E. Teller, J. Am. Ceram. Soc., 62, 1723,1940.
95. B. M. Novak, Adv Mater., 5, 422, 1993.
96. B. M. Novak, Macromolecules, 24, 5481, 1991.
97. J. M.Lin, C. C. M.Ma, F. Y. Wang, H. D. Wu, S. C. Kuang, J. Polym. Sci. Part B: Polym. Phys., 38, 1699, 2000.
98. W. P. Yang, S. L. Huang, Separ. Sci. Technol. , 38, 4027, 2003.
99. Y. Y. Yu, C. Y. Chen, W. C. Chen, Polymer ,44, 593, 2003.
100. M. Motomatsu, T. Takahashi, H. Y. Nie, W. Mizutani, H. Tokumoto, Polymer, 38, 177, 1997.
101. Z. H. Huang, K. Y. Qiu, Polymer, 38, 521, 1997.
102. X. L. Ji, S. C. Jiang, X. P. Qiu, D. W. Dong, D. H. Yu, B. Z. Jiang, J. Appl. Polym. Sci. , 88, 3168, 2003.
103. P. Hajji, L. David, J. F. Gerard, J. P. Pascault, G. P. Vigier, Polym. Sci. Part B: Polym. Phys., 37, 3172, 1999.
104. P. Bosch, F. Del Monte, J. L. Mateo, D. Levey, J. Polym. Sci. Part A: Polym. Chem. , 34, 3289, 1996.
105. B. M. Novak, M. W. Ellsworth, C. Verrier, In Hybrid Organic-Inorganic Composites ; Mark, J. E.; Lee, C.Y-C.; Bianconi, P. A., Eds.; ACS Symposium Series 585, Am Chem Soc: Washington, DC, 1995, chap. 8, pp 86-96.
106. C. J. Brinker, et al., J Non-Cryst. Solids ,100, 31,1988.
107. A. B. R. Mayer, J. E. Mark, Polymer, 41, 1627, 2000.
108. C. J. Wang, Y. Pang, P. N. Prasad, Polymer, 32, 605, 1991.
109. P. H. Sung, T. F. Hsu, Polymer, 39, 1453, 1998.
110. J. Reyes-Esqueda, B. Darracq, J. Garcia-Macedo, M. Canva, Optics Communications, 198, 207, 2001.
111. R. J. Jeng, C. C. Chang, C. P. Chen, C. T. Chen, W. C. Su, Polymer, 44 ,143, 2003.
112. B. Wang, G. L.Wilkes, J. C. Hedrick, B. C. Liptak, J. E. McGrath, Macromolecules, 24, 5121, 1991.
113. L. Guo, J. H. Lee, G. J. Beaucage, J Non-Cryst Solids, 243, 61, 1999.
114. J. M. Breiner, J. E. Mark, G. Beaucage, J. Polym. Sci. Part B: Polym. Phys., 37, 1421, 1999.
115. J. D. Mackenzie, Q. Huang, T. Iwamoto, J. Sol-Gel Techno., 7, 151, 1997.
116. J. E. Mark, et al., Polym. Eng. Sci. , 36, 2905, 1996.
117. Y. Y. Yu, C. Y. Chen, W. C. Chen, Polymer, 44, 593, 2003.
118. A. Fidalgo, M. I. L.aura, J. Non-Cryst Solids, 283, 144, 2001.
119. Y. Y. Yu, C. Y. Chen, W. C. Chen, Polymer, 44, 593, 2003.
120. X. L. Ji, S. C. Jiang, X. P. Qiu, D. W. Dong, D. H. Yu, B. Z. Jiang, J. Appl. Polym. Sci., 288, 3168, 1997.
121. T. Kokubo, S. Kushitani, T. Sakka, T. Kitsugi, J. Yamamuro, Biomed. Mater. Res. ,24, 721, 1990.
122. C. Ohtsuki, T. Kokubo, K. Takatsuka, T. Yamamuro, J. Ceram. Soc. Jpn., 22, 456, 1997.
123. C. Ohtsuki, T. Kokubo, T. Yamamuro, J. Non. Cryst. Solids, 143,84, 1992.
124. P. Li, C. Ohtsuki, T. Kokubo, K. Nakanishi, N. Soga, T Nakamura, T. Yamamuro, J. Mater. Sci.: Mater. Med., 4, 127, 1993.
125. K. Tsum, C. Ohtsuki, A. Osaka, T. Iwamoto, J.D. Mackenzie, Biomaterials, 118, 17, 1997.
126. T.Yabuta, K. Tsum, S. Hayakawa, C. Ohtsuki, A. Osaka, J. Sol-Gel Sci. Technol. 19, 745. 2000.
127. T. Kokubo, S. Ito, Z.T. Huang, T. Hayashi, S. Sakka, T. Kitsugi, T.
Yammnuro, J. Biomed. Mater. Res., 24, 331, 1990.
128. E. P. Plueddemann, Silane Coupling Agents, 2nd ed., Plenum, New
York, 1991, p. 55.
129. K. J. Herper, et al., Bioactive bone cements, Proc. Inst. Mech. Eng. Part H, 212, 113, 1998.
130. K. D. K'tihn, Bone Cement, Springer, Berlin, p. 21, 2000.
131. T. Kokubo, J. Ceram. Soc. Jpn., 99, 965 , 1991.
132. H. M. Kim, J. Ceram. Soc. Jpn., S49, 109, 2001.
133. T. Kokubo, H. Kushitani, S. Sakka, J. Biomed. Mater. Res'. 24, 721, 1990.
134. C. Ohtsuki, T Kokubo, K. Takatsuka, T. Yamamuro, J. Ceram. Soc. Jpn. (Seramikkusu Ronbunshi) 99, 1, 1991.
135. C. Ohtsuki, T. Kokubo, T. Yamamuro, J. Non- Cryst. Solids 143, 84, 1993.
136. K. Park, W. S. W. Shalaby, H. Park, Biodegradable hydrogels for drug. delivery, New York, Technomic, 1993.
137. A. S. Hoffman, Intelligent polymers, K. Park (Ed.), Controlled Drug Delivery, American Chemical Society, Washington, DC, 1997.
138. Y. H. Kim, Y. H. Bae, S. W. Kim., J. Control Release, 28, 143, 1994.
139. Y. Mori, H. Tokura, M. Yoshikawa, J. Mater. Sci. 32, 491, 1997.
140. Cha WI, Hyon SH, Ikada Y. Makromol Chem., 194, 2433, 1993.
141. T. Aoki, M. Kawashima, H. Katono, K. Sanui, N. Ogata, T. Okano, Y. Sakurai, Macromolecules, 27, 947, 1994.
142. F. X. Quinn, E. Kampff, G. Smyth, V. McBrierty, J. Macromolecules, 21, 3191, 1988.
143. J. Ratto, T. Hatakeyama, R. B. Blumstein, Polymer, 36, 2915, 1995.
144. Y. L. Guan, L. Shao, K. D.Yao, J. Appl. Polym. Sci., 61, 393, 1995.
145. D. G. Pedlev, P. J. Skelly, B. J. Tighe, Polymer, 12, 422, 1980.
146. L. C. Dong, A. S. Hoffman, ACS Symp. Set., 350, 236, 1987.
147. W. D. Oliveira, W. G. Glasser, J. Appl. Polym. Sci., 61, 81, 1996.
148. B. Pascual, I. Castellano, B. Vazquez, M. Gurruchaga, I. Goni, Polymer, 37, 1005, 1996.
149. B. Vazquez, M. Gurmchaga, I. Gore, Polymer, 36, 2311, 1995.
150. K. L. Shantha, U. Bala, K. P. Rao, Eur. Polym. J., 31, 377, 1995.
151. T. Suzuki, Y. J. Mizushima, Ferment Bioeng., 84, 128, 1997.
152. S. J. Lee, S. S. Kim, Y. M. Lee, Carbohydrate Polymers, 41, 197, 2000.
153. X. Qu, A. Wirsen, Polymer, 41, 4589, 2000.