Synthesis of poly(urethane-methacrylate) copolymers using tetraphenylethane-urethane macroinitiator by ARGET ATRP controlled polymerization method

Poly(methyl methacrylate)-b-polyurethane-b-poly(methyl methacrylate) tri-block copolymers were synthesized for the first time using ARGET ATRP method. A specially prepared for this purpose tetraphenylethane-urethane macroinitiator (TPE-PUR-TPE) was used as a transitional product reacting with methyl methacrylate (MMA) in the presence of CuBr2 or CuCl2 catalyst and N,N,N',N",N"-pentamethyldiethylenetriamine (PMDETA) or 2,2'-bipyridine (Bpy) as a complexing agent. It was found that both the molecular weight of the resulting copolymer versus MMA conversion and the value of ln([M]0/[M]) as a function of polymerization time increase linearly. High coefficients of linear correlation for the studied relationships indicate that the formation of tri-block copolymers takes place according to the mechanism of atom transfer radical polymerization. The results of FT-IR, 1H and 13C NMR spectral analyses as well as DSC and TGA thermal studies confirm the expected chemical structure of the synthesized macroinitiator and poly(urethane-methacrylate) copolymers produced with its involvement. Additionaly, the studies of surface properties (roughness, contact angle and SFE) of polymer films prepared from these copolymers indicate, based on the observed increase of hydrophobicity, the presence of block segments derived from PMMA.