Carbon nanotubes are considered to be ideal candidates for improving the mechanical properties of polymer nanocomposite scaffolds due to their higher surface area, mechanical properties of three-dimensional isotropic structure, and physical properties. In this study, we showed the improved mechanical properties prepared by backfilling of preformed hydrogels and aerogels of individually dispersed multiwalled carbon nanotubes (MWCNTs-Baytubes) and thermoplastic polyurethane. Here, we used the solution-based fabrication method to prepare the composite scaffold and observed an improvement in tensile modulus about 200-fold over that of pristine polymer at 19 wt% MWCNT loading. Further, we tested the thermal properties of composite scaffolds and observed that the nanotube networks suppress the mobility of polymer chains, the composite scaffold samples were thermally stable well above their decomposition temperatures that extend the mechanical integrity of a polymer well above its polymer melting point. The improved mechanical properties of the composite scaffold might be useful in smart material industry.