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As generally accepted, also in the case of polyamides linear and crosslinked polymeric materials are believed to be characterized by the same solution properties and, consequently, by the same solubility parameters. However, despite their great practical importance, a thorough study aimed to determine the best solvent media able to dissolve linear aromatic polyamides has not been performed yet or, at least, has not been published. In this study, we report on our study on the solubility parameters of linear and crosslinked aromatic polyamides. We demonstrate that the assumption of considering these two classes as having the same solubility properties can lead to dramatically erroneous results. Two new different sets for linear and crosslinked aromatic polyamides are proposed. Namely, linear poly(p‐phenylene terephthalamide) is characterized by δp, δd, and δHequal to 8.6, 18.4, and 11.3, respectively; by contrast, the corresponding values of the crosslinked aromatic polyamides taken into consideration are: 11.5, 16.8, and 10.2. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [ABSTRACT FROM AUTHOR]

Frontal polymerization (FP) has been successfully applied, for the first time, to obtain polymeric nanocomposites containing polyhedral oligomeric silsesquioxanes (POSS) in an amine‐cured epoxy matrix. Variations of maximum temperature (Tmax) and front velocity (Vf) have been studied. A comparison of these products with the corresponding materials, obtained by the classical batch polymerization technique, demonstrated that FP allows a higher degree of conversion than batch polymerization. The products have been characterized in terms of their thermal behavior with DSC analysis. SEM and X‐ray analyses revealed the morphology and the structures of the nanocomposites. The nanocomposites obtained by FP have the same characteristics of those synthesized, in much longer times, by batch polymerization. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4514–4521, 2007 [ABSTRACT FROM AUTHOR]

Frontal polymerization, a method that allows to convert a monomer into a polymer exploiting the exothermicity of the self‐same polymerization reaction, has been conveniently used for the easy and fast preparation of epoxy resin‐montmorillonite nanocomposites. The obtained materials have shown characteristics similar or even better than those prepared by the conventional polymerization routes. The synthetic methods and the thorough characterization of the obtained nanocomposites are described. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 2204–2211, 2007 [ABSTRACT FROM AUTHOR]