Inorganic-Organic Sol-Gel Hybrids - Bio-Glasses: An Introduction - page 152

for the samples whose surface is scarred with a knife. Thus, care should
be taken on drying to increase the concentration of -SiOH groups by
well hydrolyzing the -Si (OR) 3 groups and to secure a homogeneous
distribution of calcium ions in the surface region.
10.8 SUMMARY AND OUTLOOK
The development of inorganic-organic hybrids has led to the production
of new materials with unique combinations of properties, such as
toughness, controlled degradation, or chemical functionality. However,
synthesis of the hybrids is a complex process, and optimizing the
materials is difficult with so many variables. Their potential is massive
but development will take time. As they are new materials, translation to
clinical products is likely also to take time and to be expensive. Upscaling
laboratory-scale synthesis to mass production is also a great challenge
for chemical engineers. Having said that, hybrids may be the answer to
mimicking the hierarchical structure and properties of natural tissues
and producing materials that fit the criteria stipulated by surgeons for
their ideal implant materials.
FURTHER READING
Biodegradation of Polymers
Tabata, Y. and Ikada, Y. (1999) Vascularization effect of basic fibroblast growth factor
released from gelatin hydrogels with different biodegradabilities. Biomaterials , 20 ,
2169-2175.
Zhang, Q.Q., Liu, L.R., Ren, L., and Wang, F.J. (1997) Preparation and characterization
of collagen-chitosan composites. Journal of Applied Polymer Science , 64 , 2127-2130.
Basic Concepts of Organic-Inorganic Hybrids
Glaser, R.H. and Wilkes, G.L. (1989) Solid-state Si-29 NMR of TEOS-based multifunc-
tional sol-gel materials. Journal of Non-Crystalline Solids , 113 , 73-87.
Hu, Y. and Mackenzie, J.D. (1992) Rubber-like elasticity of organically modified silicates.
Journal of Materials Science , 27 , 4415-4420.
Huang, H.-H., Orler, B., and Wilkes, G.L. (1985) Ceramers - hybrid materials incorpo-
rating polymeric oligomeric species with inorganic glasses by a sol-gel process. 2. Effect
of acid content on the final properties. Polymer Bulletin , 14 , 557-564.
Iwamoto, T. and Mackenzie, J.D. (1995) Ormosil coatings of high hardness. Journal of
Materials Science , 30 , 2566-2570.
Mackenzie, J.D., Chung, Y.J., and Hu, Y. (1992) Rubbery ormosils and their applications.
Journal of Non-Crystalline Solids , 147 , 271-279.