Viscoelastic property enhancement of polymethylmethacrylate molecularly confined within 3D nanostructures

Abstract

Owing to its applications in various fields, such as biomedical, microelectronics, sensors, and polymer composites, polymer nanoconfinement is a widely studied topic. This confinement changes the configuration of molecules compared with those of solids, which, in the case of polymeric films, decreases the glass transition temperature and mechanical properties of the polymer. In this study, nanostructured polymethylmethacrylate, presenting three-dimensional nanoscale confinement were evaluated using amplitude modulation–frequency modulation atomic force microscopy for the first time. The Young’s moduli and loss tangents were measured, and the results suggest that for cells smaller than approximately 39 nm, the Young’s modulus of the 3-D confined polymer enhances that of the raw solid owing to reduced molecular mobility. This research shows that the molecular mobility was reduced because polymer chains were confined within three-dimensional space.