Creation of Novel Green and Sustainable Gemini‐Type Cationics Containing Carbonate Linkages

Novel gemini‐type cationics containing carbonate linkages as biodegradable and chemically recyclable segments were designed and synthesized by a green process. The carbonate linkages were introduced into only the hydrophobic moiety or in both the hydrophobic and linker moieties of gemini‐type cationics. They showed higher surface activities, such as a low critical micelle concentration value, a surface tension lowering, and a high adsorption efficiency, when compared to the corresponding single‐type cationics. Also, the gemini‐type cationics containing carbonate linkages in both the hydrophobic and the linker moieties showed stronger antimicrobial activities when compared to those only in the hydrophobic moiety. It was found that some gemini‐type cationics containing carbonate linkages showed higher biodegradability compared to the conventional gemini‐type cationics. The biodegradability of the gemini‐type cationics decreased when a carbonate linkage was introduced into the hydrophobic moiety rather than the linker moiety. However, some gemini‐type cationics containing carbonate linkages both in the hydrophobic and linker moieties showed ready biodegradability. The gemini‐type cationics containing carbonate linkages in the hydrophobic moiety showed chemical recyclability by a lipase (E.C. 3.1.1.3).