Nanofibers as interlaminar reinforcement of composites

The latter method is favorable because the nanofibrous mat (which sometimes has an area density of only 1 g/m or less) in this case will not be damaged during transport or processing which is especially important in industrialization. According to other considerations, there is no need to use a release agent between the collector and the nanofibrous mat because the collector is the reinforcement material. If metal mold is used for laminating 

Coating can be done before product preparation and pattern making when the reinforcement is available in roll or in tow formats. In this case the reinforcement material is rewound between two rollers and electrospinning takes place in between by using stationary spinneret electrode(s). Therefore, there is some technological flexibUity the production of nanofibrous interlayers can be accomplished by both the fiber manufacturer and the composite product manufacturer. 

Zhang et al. [146] investigated the effect of the thickness of the nanofibrous interleaves and the effect of nanofiber diameters on the Mode I fracture toughness, flexural and DMTA 

Finer nanofibers resulted in better improvement in the interlaminar properties without compromising the in-plane performance of the toughened composites [146], thus decreasing the fiber diameters is favorable. It must be noted that (critical energy release rate 

Increasing the thickness even more can have negative outcome. For instance, Liu et at [143] found that when the sum of the thickness of nanofibrous toughening layers reaches approximately one tenth of that of the composite, the flexural modulus and the interlaminar shear properties began to drop. When increasing the amount of nanofibers this effect becomes even more significant. 

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