Fiber hybrid

There are inter-ply hybrid RPs that have two or more fiber reinforcements embedded in the plastic matrix. They have evolved as a logical sequel to conventional single-fiber RPs. Hybrids provide unique combinations of performance feamres to meet different and competing requirements in a more cost effective way. This cost advantage has been found principally in using glass fibers with the more expensive fibers, since the 1950s. 

For example, regarding the cost of hybrid RPs, high modulus graphite-resin is about 60 times more expensive than E-glass laminates. Intermediate graphite modulus-resin is about 36 times more expensive. Aramid-resin is about 8 times as costly. Thus, when performance standards of hybrid RPs can be met, cost advantages occur. 

An almost unlimited field of possibilities continues to exist with the combination of different fibers as hybrids that, with an appropriate resin matrix, can most closely fill a specific closely identified application. In most cases, however, this is a matter for specialists, backed by an exhaustive database of fiber forms and properties. 

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Tonegawa et al. (2004) created a cationic polylysine with a tetrapeptide end sequence (glycine-tyrosine-glycine-lysine), which is a motif common to the consensus sequences of mussel adhesive proteins. They then cross-linked this with the anionic polysaccharide, gellan, enzymatically. The polyionic complexation between the cationic peptide and the anionic polysaccharide formed a hybrid fiber at the aqueous solution interface that, when cross-linked, mimicked the byssus gel that marine mussels use to adhere to surfaces, despite the presence of water and salt. 

Shao X, Hunter CJ (2007) Developing an alginate/chitosan hybrid fiber scaffold for annulus fibrous cells. J Biomed Mater Res 82A 701-710... 

Table 9,15 Charpy impact test results of square woven fabric using hybrid fibers/nylon RPs...

Polynosic fibers were produced for a time in several countries, including France, the United States, and Japan, but it soon became evident that they were too brittle for the textile market. Research workers soon began to modify the viscose and spinning conditions to produce several versions of hybrid fibers. 

LFT-G are produced by means of pultrusion. In a variant of the pultrusion process, endless fibers are drawn through a thermoplastic melt then partially or completely impregnated, depending on the production process, by means of a mold. Fig. 35. In another variant, mixtures of glass filaments and polymer filaments are used for pultrusion, so-called hybrid fibers. 

Modem dashboard constmctions are based on a supporting structure made of sheet metal, a plastic-metal hybrid, fiber-reinforced thermoplastics (GMT [PP]) or dur-oplastics (SMC [UP], SRIM [PUR]). 

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. 

Majima, T., Funakosi, T., Iwasaki, N. et al. (2005) Alginate and chitosan polyion complex hybrid fibers for scaffolds in ligament and tendon tissue engineering. Journal of Orthopaedic Science, 10, 302— 307. 

Shin, S. R., C. K. Lee, I. So et al. 2008. DNA-wrapped single-walled carbon nanotube hybrid fibers for supercapacitors and artificial vaascles.AdvancedMaterials 20 466-470. 

A complementary approach to the fabrication of nanotubes involves the use of hard templates as tools. Hard templates are either nanofibers or porous host materials. In the former case, the nanofibers are at first coated with the waU material of the tubes or a corresponding precursor. Subsequently, the template fiber, that is, the core of the hybrid fiber thus obtained, is selectively removed so that a shell of the material initially deposited onto the template nanofiber is conserved. Template fibers can, for example, be produced in high... 

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. ... 

Y Kuboe, H Tonegawa, K Ohkawa H Yamamoto, Quinone cross-linked polysaccharide hybrid fiber. Biomacromolecules, 20W 5 348-357. 

It should be noted that there is not simply an addition of thermotropic LCPs into fiber-reinforced plastics to get in situ hybrid composites. Bafna et al. used glass fibers to decrease the anisotropy of LCP fibril-reinforced polyetherimide [136]. He et al. improved the processability and mechanical performances of glass fiber-reinforced polypropylene by the addition of LCPs [159]. However, these two works did not actively and purposely generate a reinforced composite with the reinforcements having their diameters at two orders of magnitude. The key point for in situ hybrid composites is the formation of LCP fibrils in the material system. As a combination of in situ composite and hybrid fiber reinforcing, the fabrication of in situ hybrid composites utilizes fabrication... 

Kalaprasad G, Thomas S (2003) Melt rheological behavior of intimately mixed short sisal-glass hybrid fiber-reinfOTced low-density polyethylene composites. II chemical modification. J Appl Polym Sci 89 443-450... 

Kalaprasad G, Francis B, Thomas S et al (2004) Effect of fiber length and chemical modifications on the tensile properties of intimately mixed short sisal/glass hybrid fiber reinforced low-density polyethylene composites. Polym Int 53 1624—1638... 

Different kinds of biobased polymeric materials are available all around the globe. These biobased materials are procured from different biorenewable resources. Chapters 2-10 primarily focus on the use of different types of lignocellulosic fiber-reinforced composites, starting from wood fibers to hybrid fiber-reinforced polymer composites. Chapter 3 summarizes some of the recent research on different lignocellulosic fiber-reinforced polymer composites in the Southeast region of the world, while Chapter 6 summarizes the research on some typical Brazilian lignocellulosic fiber composites. The polymers obtained from biopolymers are frequently referred to as biobased... 

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]. 

G. Kalaprasad, S. Thomas, C. Pavithran, N.R. Neelakantan, S. Balakrishnan, Hybrid effect in the mechanical properties of short sisal/glass hybrid fiber reinforced low density polyethylene composites. /. Reinf. Plast. Compos. 15,48-73 (1996). 

A. Haneefa, P. Bindu, 1. Aravind, and S. Thomas, Studies on tensile and flexural properties of short banana/glass hybrid fiber reinforced polystyrene composites. J. Compos. Mater. 42, 1471-1489 (2008). 

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