PET and Layered Silicates Nanocomposites

During the last years, much attention has been paid to polymer/ layered silicate nanocomposites because remarkable improvements can be expected in mechanical, thermal, flame resistant and physicochemical properties compared to their base polymers or conventional composites (37,38). 

Several authors reported the preparation of PET/ layered silicate nanocomposites. The main procedures used for nanocomposites preparations are melt polymerization, common solvent mixing and in-situ polymerization. In most cases, intercalated nanocomposites were obtained. 

Intercalated PET montmorillonite clay nanocomposites were compounded via melt-blending in a corotating mini twin-screw extruder. Nanocomposites compounded with l,2-dimethyl-3-N-hexadecyl imidazolium treated montmorillonite showed higher levels of dispersion and delamination than those with a typical quaternary aimnonium salt (39). 

Intercalated nanocomposites of PET and layered silicate were prepared with different kinds of cationic surfactants as compatibilizers by a two-step pol)unerization process a melt polymerization of bis-(2-hydroxyethyl)terephthalate followed by a solid state polymerization. The obtained nanocomposites showed a higher tensile storage modulus compared with those prepared without compatibilizers (40). 

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