Mechanical Behavior of Bioactive Glass-Polyvinyl Alcohol Hybrid Foams Obtained by the Sol-Gel Process
The possibility of enhancing mechanical properties by incorporation of polymeric components to sol-gel derived materials is extremely attractive to prepare macroporous scaffolds, leading to materials with potential applications in both hard and soft tissue regeneration. In this work bioactive glass-polyvinyl alcohol hybrids were developed and their mechanical behavior was evaluated. Hybrids were synthesized by adding polyvinyl alcohol to a sol-gel precursor solution, which was then foamed with the addition of a surfactant and vigorous agitation. The foams were cast, aged and dried at 40°C. A cleaning step to decrease the acidic character of the obtained hybrids was undertaken by immersion in a NH4OH solution. The mechanical behavior of the hybrids was evaluated in compression using both stress and strain control tests. Hybrid foams had a high porosity varying from 60-90% and the macropore diameter ranged from 10 to 600 µm. The modal macropore diameter varied with the inorganic phase composition and with the polymer content in the hybrid. The strain at fracture of the as prepared hybrid foams was substantially greater than pure gel-glass foams. The cleaned hybrids presented a slightly higher strength and lower deformation than the as prepared foams.
Panjian Li, Kai Zhang and Clifford W. Colwell, Jr.
M. Pereira et al., "Mechanical Behavior of Bioactive Glass-Polyvinyl Alcohol Hybrid Foams Obtained by the Sol-Gel Process ", Key Engineering Materials, Vols. 284-286, pp. 757-760, 2005