Novel polydimethylsiloxane (PDMS) composites reinforced with three-dimensional continuous silica fibers

The ultimate goal in the preparation of composite materials, which is difficult to achieve, is the uniform dispersion of fillers within a polymer matrix to form an interconnected network. Herein, we prepared novel polydimethylsiloxane (PDMS) composites loaded with three-dimensional (3D) continuous silica fibers (i.e., silica sponge). In the composites, silica fibers maintained continuous fibrous structure, achieved uniform distribution, and showed strong interfacial adhesion with PDMS, which together contributed to a dramatic improvement in mechanical properties compared with pure PDMS and PDMS loaded with glass fibers. With a loading level of only 1 wt%, the tensile modulus, strength, strain-at-break, and tear strength of the composites improved by 140%, 94%, 18%, and 95%, respectively, compared to PDMS. In addition, these composites retained good transparency. More importantly, this silica fiber filler system is widely applicable and can be used to prepare various high performance polymer composites.