Post-functionalization and Mechanical Properties of Poly(lactide-cyclohexadiene oxide) Block Copolymers

A series of lactide (LA) and cyclohexadiene oxide (CHDO) multiblock copolymers was synthesized using a redox switchable complex, (salfen)Zr(OiPr)2 (salfen = N,N’-bis(2,4-di-tert-butylphenoxy)-1,1’-ferrocenediimine), with LA being polymerized by the reduced state, while CHDO was polymerized by the oxidized state of the catalyst. Diblock (PCHDO-PLA) and triblock (PLA-PCHDO-PLA and PCHDO-PLA-PCHDO) copolymers were prepared, and all the copolymers were post-functionalized using a thiol-ene click reaction. Dynamic mechanical analysis showed that both triblock copolymers have a better elasticity than the diblock copolymer, and all the functionalized copolymers have a better elasticity than the corresponding non-functionalized copolymers.