Shape Memory Polymer (SMP) Foams for Bone Defect Repair

Thermoresponsive shape memory polymers (SMPs) are stimuli-sensitive materials that return to their permanent shape from a fixed temporary shape in response to heat. Porous SMP foams exhibit distinct properties that make them well suited for certain applications in the biomedical field. However, current SMP foams are restricted to a limited group of organic polymer systems. Inorganic-organic foams containing polydimethylsiloxane (PDMS) and poly(ε-caprolactone) (PCL) segments prepared from diacrylated PCLn-block-PDMSm-block-PCLn have recently been reported by our research group. These SMPs exhibit excellent biological, morphological and mechanical properties that may be attractive for “self-fitting” scaffolds to heal cranio-maxillofacial (CMF) bone defects whereby application of warm saline triggers the SMP to expand and conformably fit into a defect before cooling and hardening at body temperature. To enhance the resorption capacity of the scaffolds, the PDMS component may be substituted with a degradable poly(silyl ether fumarate) (PSEF) segment. Herein, two synthetic strategies toward PCLn-block-PSEFm-block-PCLn were explored. Synthetic approaches toward PSEF-diacrylate (i.e. without PCL) are also investigated