Nanoparticles materials Polymer-grafted

For the manufacture of long term products, such as automobile and aerospace components, sporting goods, etc., it is recommended the grafting of nanoparticles on polymer backbones. This goal is accomplished in the case of PP [105] and PU [106] by the exposure of hybrid materials to the action of y-radiation. 

Coram et al. [6] have described the polymer support as a soluble macromolecule or a micellar aggregate that wraps the metal nanoparticle in solution, thus preventing metal sintering and precipitation. It can also be a resin, that is an insoluble material consisting in a bundle of physically and/or chemically cross-linked polymer chains in which the metal nanoparticles are embedded (Figure 11.2). Thus, soluble cross-linked polymers ( microgels ) that can stabilize metal nanoparticles can be prepared in addition, metal colloids protected by soluble linear polymers have been grafted onto insoluble resin supports to yield insoluble catalysts. This chapter is devoted mainly to metal nanoparticles on insoluble resin supports [8]. 

The linear viscoelastic properties in the melt state of highly grafted polymers on spherical silica nanoparticles are probed using linear dynamic oscillatory measurements and linear stress relaxation measurements. While the pure silica tethered polymer nanocomposite exhibits solid-like response, the addition of a matched molecular weight free matrix homopolymer chains to this hybrid material, initially lowers the modulus and later changes the viscoelastic response to that of a liquid. These results are consistent with the breakdown of the ordered mesoscale structure, characteristic of the pure hybrid and the high hybrid concentration blends, by the addition of homopolymers with matched molecular weights. 

MMA, and St from magnetite nanoparticles functionalized with an organophosphono initiator, was reported by Babu and Dhamodharan [107c]. Mesoporous hybrid materials made of mesoporous silica and a covalently grafted polymer with controlled chain length were successfully synthesized by surface-initiated ATRP of St and MMA [107d]. 

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