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Nylon 6/6 nanofibers of diameter 80–100 nm were electrospun on bidirectional E-glass fabric. The fabric with nanofibers on one surface was used to fabricate glass/epoxy structural composites, through resin film infusion. Mechanical properties of composites with interleaved nylon 6/6 nanofibers were found to be substantially improved from that of the control specimens fabricated under identical conditions, but without nanofibers. Compressive strength of composites showed over 30% increase, while interlaminar shear strength improved by 17% with nylon nanofibers of an areal density as low as 0.4 gsm. Residual compressive strength of laminates after a low-velocity impact event also showed a promising improvement with interleaved electrospun nanofibers.

Resin Film Infusion (RFI) has been used to fabricate composites with continuous unidirectional E-glass and epoxy with low weight fractions of carbon nanotubes (CNTs) in matrix. An ultrasound-assisted dissolution-evaporation method with thermoplastics or block copolymers as dispersing agents for nanoparticles enabled uniform dispersion of CNTs in the resin. Rheological characterization of CNT-filled epoxy revealed that viscosity, and hence processing of the resin remains unaffected as compared to pristine resin at elevated temperatures of subsequent composite manufacturing. Local flow of the modified resin through the sandwiched fabric plies in RFI process as against the global flow in traditional liquid composite molding processes, made sure that uniform distribution of nanoparticles is accomplished throughout the composite. Compressive properties of hybrid composites improved considerably with CNTs at loading fractions as low as 0.2 wt %.

Structural composites based on unidirectional E-glass and epoxy have been fabricated through resin film infusion. Low weight fractions of carbon nanofibers are dispersed in epoxy resin using a solvent-assisted ultrasonication process. Rheological characterization of carbon nanofiber-filled epoxy revealed that viscosity, and in turn processing characteristics of the resin remain almost unaffected as compared to the pristine resin system at elevated temperature of composite processing. Glass transition temperature of epoxy showed a considerable improvement with carbon nanofibers. Local flow of the modified resin through the embedded fabric plies in the resin film infusion process made sure that a uniform distribution of nanoparticles is achieved throughout the composite. Compressive strength of hybrid composites showed over 40% increase while interlaminar shear strength improved by 33% with carbon nanofibers at a loading fraction as low as 0.5 wt%.