Thermosetting Systems with Nanostructures

The addition of nano structured modifiers provides thermosets with special mechanical properties or functionality. Among such modifiers, the two types most widely used are block copolymers and nanoparticles (or fillers). 

Block copolymers have long been applied to modify thermosets, since the first reports made by Bates [78]. The rheology of the order-disorder transition of diblock copolymers in epoxy monomers was first studied by Fine et al. [79], who suggested that a solid-like to a liquid-like transition would correspond to such a structural transition due to the solubility changes that occur around the transition. Subsequently, Serrano et al. [80] examined the rheological behavior of an epoxi-dized styrene-butadiene linear diblock copolymer-modified epoxy with nanostructures. An increase in the magnitude of both the viscosity and the moduli was detected for the block copolymer-modified blends just before gelation, associated with the reaction-induced microphase separation (RIPS). 

Nanoparticle-modified thermosets are known to differ greatly from neat thermosetting resins. With the effects of fillers on the chemorheology of thermosetting resins having been studied for decades [7], rheological models are today basically 

Chen et al. [88] studied the interlayer expansion mechanism of MMT in epoxy resins by using time-resolved, high-temperature X-ray diffraction (XRD), DSC and isothermal rheological analyses, and found that the interlayer expansion 

10 rad s- for epoxy/Nanofil dispersions at dif- Ref [87] 2008, John Wiley Sons, Inc. ferentclay loadings 0 per 100 parts of resin 

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