Protein–polymer hybrid oil–absorbing gel using hair keratin as macroinitiator by SET-LRP

Biological macroinitiator for single electron transfer-living radical polymerization was designed from extracted human hair keratin by nucleophilic reaction of amino group with 2-bromoisobutyryl bromide. Homogeneous polymer–protein hybrid oil–absorbing gel was synthesized by copolymerization of acrylate with a small amount of cross-linker using keratin-Br macroinitiator. The variation of gelation properties including gelation time, gel fraction and oil absorbency was studied by changing monomer composition , initiator type, and cross-linker structure. The gelation time did not change significantly by varying the substitution degree of macroinitiator. Aromatic cross-linker was more prone to form microgel and higher oil absorbency was achievable with longer oleophilic chain of acrylate. The polymer–protein was obtained with the maximum oil absorption of chloroform reaching 43.7   g   g −1 and performed good reusability.