Synthesis of Photoactuating Acrylic Thermoplastic Elastomers Containing Diblock Copolymer-Grafted Carbon Nanotubes

A photoactuating nanocomposite was prepared by the in situ grafting of carbon nanotubes with PBA-b-PMMA diblock copolymer during the synthesis of the linear triblock copolymer poly(methyl methacrylate)-b-poly(n-butyl acrylate)-b-poly(methyl methacrylate) (PMMA-b-PBA-b-PMMA). Control over the molecular characteristics of the block copolymers was achieved by applying atom transfer radical polymerization. This synthetic approach allowed for the excellent dispersion and distribution of carbon nanotubes within the polymer matrix. The final nanocomposite containing 1 wt % grafted carbon nanotubes exhibited improved elasticity compared to that of the pure triblock copolymer, as demonstrated by dynamic mechanical analysis and rotational rheology measurements. The photoactuating behavior of the nanocomposite was demonstrated by thermomechanical analysis.