One-Pot Synthesis of Block Copolymers via ATRP and ROP Using PCL Macroinitiator

Abstract

Poly(lactide)-b-poly(ε-caprolactone)-b-poly(styrene) triblock copolymers were synthesized simultaneously by one-pot method using atom transfer radical polymerization (ATRP) and ring-opening polymerization (ROP) in one step. Firstly, brominated poly(ε-caprolactone) (PCL-Br) as macroinitiator was made via ROP of ε-caprolactone (ε-CL) in the existence of tin(II) 2-ethyl hexanoate at 110 °C followed by esterification with 2-bromopropionyl bromide. With the one-pot method, the simultaneously via ROP of D, Llactide in the existence of tin(II) 2-ethyl hexanoate and ATRP of styrene (St) monomer with PCL-Br macroinitiator in the presence of CuCl/PMDETA system using [I]: [CuCl]:[PMDETA]=1:1:3 molar ratios at 120 °C in toluene was performed. Thus, the block copolymers with controlled molecular weights and moderately narrow polydispersities were obtained. Principal parameters, such as monomer concentration, initiator concentration, and polymerization time, which effect the one-pot polymerization were investigated. The polymers obtained were characterized using 1H NMR, FTIR, and GPC technique.