Inorganic fillers polymer matrices

Chung, T.S., Jiang, L.Y., li, Y., and Kulprathipanja, S. (2007) Mixed matrix membranes (MMMs) comprising organic polymers with dispersed inorganic fillers for gas separation. Prog. Polym. Sci., 32 (4), 483-507. 

Many researchers have shown that incorporation of nanoscale dimension particles (inorganic fillers, nanotubes, nanofibers etc) into a polymer matrix enhances the mechanical properties of the polymer without significantly raising its density or sacrificing its light transmission property. For instance, the Toyota research groups... 

Reinforced polymers with inorganic fillers are known to show greater resistance to radiation than original polymers. Most of organic materials in fusion reactors must be designed to employ organic-matrix composites as it appears very doubtful that conventional polymers can withstand the severe radiation environment for a reasonably long operation time. 

Typically, titanate-treated inorganic fillers or reinforcements are hydrophobic, organophilic, and organofunctional and, therefore, exhibit enhanced dispersibility and bonding with the polymer matrix. When used in filled polymer systems, titanates claim to improve impact strength, exhibit lower viscosity, and enhance the maintenance of mechanical properties during aging. 

According to IK-spectroscopy inorganic filler is inert in the relation to polymeric matrix because the identical spectra of absorption of initial unfilled polymer and the polymer filled with inorganic filler are the same. Hence, mechanical behavior of PCM is defined by structural organization of composite materials, its dependence on conditions of formation and test on PCM (in our case, speed of deformation). 

The most commonly studied polymer nanocomposites are clay-based nanocomposites, mainly with montmorillonite (MMt) as layered silicate filler (Scheme 15.12). Upon incorporation of organomodihed clays (organoclays) into a polymer matrix, two nanomorphologies (Scheme 15.13) can be obtained, either intercalation of the polymer chain in between the clay platelets keeping the stacking of the sheets, or exfoliation of the clay platelets with a disordered dispersion of the inorganic sheets in the polymer. 

Polymer nanocomposites are combinations of polymers containing inorganic or organic fillers of definite geometries (fibres, flakes, spheres, particulates and so on). The use of fillers, which have one dimension on the nanometre scale, enables the production of polymer nanocomposites. Functional nanocomposites with specific properties can be custom-made by combining metal nanoparticles (MNP) into the polymer matrix. 

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