Hybrid fiber mat

In both studies shown above, the authors dried the hybrid fiber mat prior to molding. The importance of the drying stage lies in the fact that the high content of moisture of natural fibers is detrimental for the properties of the composite [2], since, in combination with the hydrophobic character of the polymer matrix, is responsible for void formation and weak adhesion [59]. 

Very recently, vanadium dioxide hybrid fiber mats (PVPA 02) were prepared for the first time and their diffuse reflectance was investigated [36]. 

Table 7. Tensile and flexural mechanical properties of hybrid fiber mat-reinforced (CeF/GF) hybrid composites as a function of the fiber surface treatment T - tensile, F - flexural.

Thermoplastics - long fiber-reinforced, textile-reinforced, woven mat-rein-forced or with local hybrid fiber reinforcement - will gain ground in the direction of large-scale production series and structural parts production. 

Figure 8.6 shows the TEM images of silver/polypyrrole/ polyacrylonitrile composite nanofibrous mats prepared. It was reported that low AgN03 content could decrease the diameters of the Ag/PAN fibers and higher AgNOs concentration led to increase in the diameters of the hybrid fibers due to the high content of the solute in the electrospinning solution. ... 

Although introducing micro-particles into an electrospun fiber mat enhances the hydrophobicity, the main problem associated with a fiber/particle hybrid membrane is that it is not robust mechanically under deformation and wear conditions, the disconnected particle component is readily lost from the membrane. Processing the fibers with a beaded morphology as described above solves the problem of wear, but it remains likely that the enhanced hydrophobicity is due to the introduction of beads rather than fibers as points of contact with the water drop. One way to enhance the hydrophobicity of electrospun hber mats without introducing microparticles (beads) is to make hierarchically roughened hber mats, where hner-scale structures (e.g. nanometer scale particles or pores) are decorated on a coarser-scale structure associated with the hbers. This is reviewed next. 

Ge Z, Yang F, Goh J CH, Ramakrishna S and Lee EH. Biomaterials and scaffolds for ligament tissue engineering. J Biomed Mat Res. 2006 77 639-652. Majima T, Funakosi T, Iwasaki N et al. Alginate and chitosan polyion complex hybrid fibers for scaffolds in ligament and tendon tissue engineering. 7 Orthop Sci. 2005 10 302-307. 

Beyond fibers and fiber mats, electrospinning can be fruitfully employed to design hybrid membranes [68,69]. Especially, the condensation of silica precursors tetraethyl orthosilicate and a sulfonated chlorosilane during electrospinning in the presence of a fluorinated polymer has been used to allow intimate mixing of a siliceous inorganic framework and an organic polymeric component [68]. 

DuPont has announced that they will produce hthium-ion battery separators using their Hybrid Membrane Technology (HMT), which is based on a nontraditional electrospinning process. Currently a nano-fiber mat is available based on nylon. Products for lithium-ion batteries are yet to be aimounced. 

Note X=in-plane 0°, Y=in-plane 90°, Z = through thickness, Vf=fiber volume fraction, M=mat VGCF, H=hybrid VGCF, S=short staple VGCF, P=P-55 fiber, E=cpoxy, CER=cyanate ester resin. 

Mazzola et al used polyesters for foamed composites (6). Narkis et al (27) described foamed polyester composites made using random glass mat. Saidla et al (28) reported making foamed polyester composites using -inch glass fibers. Vinyl ester/styrene copolymer foams were developed by Olstowski and Perrish (10, 11). Vinyl ester-based hybrid-foam composites were developed by Frisch and Ashida (19). 

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