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Highly transparent nanocompositeswere produced by in situ generationof titania network into an aromatic polyamide through a sol–gelprocess. These nanocomposites were fabricated using two differentstrategies, system-I involved the interaction of hydroxyl groups presenton the backbone of the matrix with tetraisopropylorthotitanate (TPOT),while in system-II, 3-isocyanatopropyltriethoxysilane (ICTS) was exploitedfor extensive bonding between titania and hydroxyl groups of aromaticpolyamide derived from the condensation of different diamines andterephthaloyl chloride. Thin nanocomposite films were analyzed fortheir structural, optical, mechanical, thermal, and morphologicalanalyses. FTIR data confirmed the formation of nanocomposites andinteraction among the phases. Tensile properties of these materialswere improved with increasing titania content relative to pure polyamide.FESEM micrographs clearly showed homogeneous distribution of titaniaat nanolevel in the matrix. Thermal decomposition and glass transitiontemperatures of nanocomposites were found in the ranges 450–550°C and 285–328 °C, respectively, depicting high thermalstability and interactions between the two phases. [ABSTRACT FROM AUTHOR]

Aminosilane grafted and diamine modifiedreactive montmorillonitewas exploited to generate aromatic polyamide based nanocomposites.For better compatibility, the hydrophilic nature of montmorillonitewas changed into organophilic using 1,4-phenylenediamine, and thehydroxyl groups present on the clay surface and edges were used tograft 3-aminopropyltriethoxysilane (APTS) on clay sheets. The dispersionof clay was monitored in the polyamide obtained from 1,4-phenylenediamine,4,4′-oxydianiline, and isophthaloyl chloride. These chainswere converted into carbonyl chloride ends to interact with free aminegroups of grafted APTS and diamine. Thin films were probed for FTIR,XRD, SEM, TEM, tensile testing, TGA, and DSC measurements. The resultsdescribed ample dispersion of clay in the nanocomposites with tensilestrength increased 110% and elongation increased 172% upon the additionof 4–6 wt % clay. Thermal decomposition temperatures of thenanocomposites were in the range 425–480 °C. The glasstransition temperature increased up to 142.4 °C with 6 wt % additionof organoclay. [ABSTRACT FROM AUTHOR]