Reduction of the glass transition temperature of confined polystyrene nanoparticles in nanoblends

The role of nanoconfinement on the glass transition temperature (T-g) of polymers has been extensively studied in the thin film geometry. This work looks at the T-g of nanoconfined polystyrene (PS) in spherical nanoparticles (27-200 nm), individually dispersed in crosslinked polybuthylmethacrylate matrices. A reduction of T-g compared to the bulk was observed in PS nanospheres via neutron scattering mechanical tests and was found to decrease with decreasing diameter for D < 50 nm. The general trend of T-g depression in nanospheres was found to be similar to the results on thin film geometry.