Recyclable polymers offer a great opportunity to address the environmental issues of plastics.Herein,functionalization of recyclable polymers,poly ((R)-3,4-trans six-membered ring-fused GBL) (P ((R)-M)),were reported via end-group modifications and block/random co-polymerizations.Di-n-butylmagnesium was selected to catalyze ring-opening polymerization (ROP) of (R)-M in the presence of a series of functional alcohols as the initiators.Block/random copolymerizations of (R)-M and e-caprolactone (e-CL),L-lactide (L-LA) and trimethylene carbonate (TMC) were performed to control the onset decomposition temperature (Td),melting temperature (Tm) and glass transition temperature(Tg).These functionalized recyclable polymers would find broad applications as the sustainable plastics.