Question

Propose a method for the synthesis of a block copolymer of Polystyrene-b-poly (methyl methacrylate) (PS-b-PMMA) by living anionic polymerization (LAP), followed by ATRP (transformation of LAP to ATRP). Write down the reaction scheme.

Answer 1

The first step of the synthesis would be to form the anionic propagating species in a process of living anionic polymerization (LAP) starting with styrene and n-Butyllithium as the initiator in a cyclohexane solvent.

Then, ethylene oxide in cyclohexane is added to generate a new anionic propagating species.

The propagating species is subsequently acylated with trichloroacetyl chloride in cyclohexane to generate a deactivated acylated species.

The deactivated acetylated species generated above acts as the macroinitiator in an Atom transfer radical polymerization (ATRP) process. Here, CuCl/bpy acts as the transition metal catalyst system and the monomer is Methyl methacrylate (MMA). The solvent used is toluene.