Thermoresponsive Shape-Memory Aerogels from Thiol–Ene Networks

Thermoresponsive shape-memory polymer aerogels have been produced from thiol–ene networks of 1,6-hexanedithiol, pentaerythritol tetrakis(3-mercaptopropionate), and triallyl-1,3,5-triazine-2,4,6-trione. The thiol–ene networks form organogels with either acetonitrile or acetone as the solvent, which can be subsequently removed using supercritical CO 2 extraction. The resulting aerogels have nearly quantitative shape fixing and shape recovery with a glass transition temperature ranging from 42 to 64 °C, which serves as the thermal transition trigger for the shape-memory effect. The aerogels have a porosity of 72% to 81% but surface areas of only 5–10 m 2 /g.