Synthesis and characterization of novel polysiloxane based ABA-type triblock copolymers using ATRP

Novel polysiloxane based ABA-type triblock copolymers having a secondary amine at the junction point were synthesized using a combination of ring opening equilibration polymerization (ROEP), Michael addition and atom transfer radical polymerization (ATRP). Polysiloxane based bifunctional ATRP macroinitiators were synthesized and subsequently used for controlled radical polymerization of t-butyl acrylate (t-BA) and sulfobetaine methacrylate (SBMA). Gel permeation chromatography (GPC) analysis of the triblocks based on t-BA showed high chain end functionality, due to the disappearance of peaks related to the macroinitiator. ROEP can be used to control the block length of the polysiloxane while ATRP can be used to control the chain length of the outer blocks, making the ABA- type triblock a unique material with secondary amine functionality which can be used for further reaction