2.3 Nanofillers 43 20wm1500X a 204m1500X Figure 2.7.Carbon black in the form ofaporous agglomerate of nanopartides.a Before compression.b After compression Carbon nanofibers commonly have an intertwined morphology(Fig.2.4)akin to cotton wool.This means that the nanofibers tend to clump together,making it diffi- cult to disperse them.Figure 2.10 illustrates a nonuniform filler distribution due to clumping and a uniform filler distribution in the absence of clumping.A relatively high degree of mechanical agitation,as achieved in high-shear mixing,is typically needed during composite fabrication in order to alleviate the clumping problem.2.3 Nanofillers 43 Figure2.7. Carbon black in the form of a porous agglomerate of nanoparticles. a Before compression.bAfter compression Carbon nanofibers commonly have an intertwined morphology (Fig. 2.4) akin to cotton wool. This means that the nanofibers tend to clump together, making it diffi- cult to disperse them. Figure 2.10 illustrates a nonuniform filler distribution due to clumping and a uniform filler distribution in the absence of clumping. A relatively high degree of mechanical agitation, as achieved in high-shear mixing, is typically needed during composite fabrication in order to alleviate the clumping problem