Flame retardant polymer blends with nanoparticles

3 Flame retardant polymer blends with nanoparticles 

Most engineered plastics mix with more than two polymers. It is hard to achieve flame retardant formulations because the microstructures of polymer blends are continuously changing during heating, which can result in phase separation. Even though the functionalized clays can be exfoliated and/or intercalated in homopolymers, it is necessary to consider the interfaces in polymer blends. Recently, Si et al. [5] showed that when Cloisite clays 

An alternate method for achieving similar results was recently proposed by Pack et al. [10], who showed that RDP-coated clays can also compatibilize polymer blends, and are even more effective than Cloisite 20A clays when the blends contain styrenic components. In this case, the FR did not compete with the polymers for the clay surfaces, because both polymers also adsorbed onto the RDP-coated surfaces. As a result, addition of these clays improved the mechanical properties of the blends and resulted in a material that was able to pass the UL-94 VI flame test. 

PS/PMMA/FR/Cloisite 20A with multiwall carbon nanotubes (MWCNTs) 

It was shown that the addition of organoclays, such as Cloisite 20A, can enhance the compatibilization of the blends. However, when the blend was also required to be selfextinguishing, significantly higher concentrations of clay were required. Furthermore, because the blends also contained 15-18% of the FR formulation and at least 10% by weight 

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