Convenient synthesis of versatile syndiotactic polystyrene materials containing pendant alkenyl groups with a scandium catalyst system

The syndioselective copolymerization of styrene (St) with five alkenyl functionalized styrenic monomers with the use of [(C₅Me₄SiMe₃)Sc(CH₂C₆H₄NMe₂-o)₂]/[Ph₃C][B(C₆F₅)₄] produced a new family of versatile syndiotactic polystyrene (sPS) materials with pendant alkenyl groups (CC: 5–20 mol%, T_m: 220–250 °C). These styrenic monomers were divinylbenzene (FSt1), 4-isopropenylstyrene (FSt2), 4-(1-isopropylvinyl)styrene (FSt3), 4-(2-propenyl)styrene (FSt4) and 4-(2-methyl-2-propenyl)styrene (FSt5). Through thiol–ene click chemistry and epoxidation, new polar-group functionalized sPS materials were obtained efficiently, demonstrating that syndiotactic copolymers with pendant alkenyl groups can serve as reactive intermediates to produce various functional materials.