In accordance with one embodiment, a polymer composite comprises a filler and a matrix. The filler comprises an electrospun polymer mat. The matrix comprises a polymer film. The filler is arranged to respond to stimuli by altering its mechanical properties. In one example, the mat can be electrospun from poly(vinyl alcohol), and the matrix can be formed from ethylene oxide-epichlorohydrin 1:1 copolymer. The filler can be arranged so that the tensile storage modulus of the polymer composite changes in response to the filler being exposed to a stimulus. In another example, the filler is about four percent by weight of the polymer composite.