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Crosslinkable PEO-PPO-PEO-based reverse thermo-responsive gels as potentially injectable materials.

Alejandro Sosnik·Daniel Cohn·Julio San Román·Gustavo A Abraham
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Abstract

This paper describes the functionalization and crosslinking of PluronicRTM derivatives in aqueous solution at 37 degrees C. Pluronic dimethacrylate was obtained by reacting native PEO-PPO-PEO triblocks with methacryloyl chloride and then crosslinking them by free radical polymerization at 37 degrees C, using a redox system. The resulting gel and its rheological behavior were characterized by different techniques. The swelling study of the crosslinked polymer was indicative of its reverse thermo-responsive behavior, as illustrated by the almost 800% water uptake of the polymer at 37 degrees C, as opposed to the 1600% attained by the polymer at 25 degrees C. As expected, while the Pluronic dimethacrylate gel displayed an Ec value of 142.5 +/- 29.7 kPa at 37 degrees C, the crosslinked system attained a Young's modulus three times higher: 415.2 +/- 45.7 kPa. Finally, the environmental SEM analysis revealed the porous microstructure of the crosslinked gels.

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Biocompatible MaterialsCross-Linking ReagentsGelsInjectionsPolyethylene GlycolsPropylene GlycolsSolutionsThermodynamicsViscosityJournal ArticleResearch Support, Non-U.S. Gov't

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Alejandro Sosnik, Daniel Cohn, Julio San Román, Gustavo A Abraham. 2003. Crosslinkable PEO-PPO-PEO-based reverse thermo-responsive gels as potentially injectable materials.. https://doi.org/10.1163/156856203763572680

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