Biodegradations of block copolymers composed of L‐ or D,L‐lactide and six‐membered cyclic carbonates prepared with organolanthanide initiators

Diblock copolymerizations of L ‐ or D,L ‐lactide (LA) with trimethylene carbonate (TMC) or 2,2‐dimethyltrimethylene carbonate (2,2‐DTMC) with SmMe(C 5 Me 5 ) 2 ‐(tetrahydrofuran) as an initiator and triblock copolymerizations of L ‐ or D,L ‐LA/cyclic carbonates/ L ‐ or D,L ‐LA with [Sm(C 5 Me 5 ) 2 ] 2 (PhCCCCPh) as an initiator generated the desired block copolymers. This article describes the comparison of biodegradabilities by proteinase K and a compost and mechanical properties between the resulting di‐ or triblock copolymers and random copolymers composed of L ‐ or D,L ‐LA and cyclic carbonates. The scanning electron microscopic profiles of resulting polymers were measured to understand the morphological change during biodegradation.