BEH.462/3. 962J Molecular Principles of Biomaterials Spring 2003 Structure of Associating Block Copolymer Hydrogels Pluronics( trade name, BASF)are an important class of hydrophobically-associating block copolymers: FDA approved for use in vivo Starting at relatively low concentrations, Hydrophilic-hydrophobic block copolymers form micelles upon passing a critical concentration(cmc)or temperature(cmt) O ON BOARD unimers micelles doweromicelle ncreasing c, T Core-shell micelle s Hydrophilic block o At higher concentrations, micelles overlap and gelation can occur o Micelles pack together Interactions between micelles depend on structure of block copolymer 路 Intermicelle physical cross links Entanglement of packed micelle coronas Lecture 8 sical gels 8of12BEH.462/3.962J Molecular Principles of Biomaterials Spring 2003 Lecture 8 – Physical gels 8 of 12 Structure of Associating Block Copolymer Hydrogels4 ƒ Pluronics (trade name, BASF) are an important class of hydrophobically-associating block copolymers: FDA approved for use in vivo ƒ Starting at relatively low concentrations, Hydrophilic-hydrophobic block copolymers form micelles upon passing a critical concentration (cmc) or temperature (cmt)2 o ON BOARD: Increasing c, T Hydrophobic block Hydrophilic block unimers micelles ŌflowerÕ micelle Core-shell micelle o At higher concentrations, micelles overlap and gelation can occur: o Micelles pack together ƒ Interactions between micelles depend on structure of block copolymer: Intermicelle physical cross-links Entanglement of packed micelle coronas