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The melt synthesis of poly(butylene succinate)/silica (PBS/SiO2) nanocomposites is investigated via an in situ approach. The use of two types of nanosilica, fumed (or pyrogenic) silica and colloidal silica, is described. In all cases, the addition of silica favors an increase of the melt viscosity during the polycondensation step. This behavior is attributed to both polymer–silica interactions and PBS chain coupling via possible reaction with silica silanols. Biodegradable film is a promising application for PBS. In this context, it is proved that silica greatly facilitates PBS processing by extrusion blowing (a longitudinal draw ratio of 16 is attained). Moreover, tensile tests performed on films demonstrate significant reinforcement of the material with the addition of the nanofiller. The dispersion of the particles into the polymer matrix is assessed by transmission electron microscopy and further characterized by image analysis. It appears that pyrogenic and colloidal silica particles are regularly dispersed in the polymer matrix and that this dispersion is stable upon film blowing.

New catalytic systems are developed to increase the transesterification efficiency during the synthesis of poly(ethylene terephthalate-co-isosorbide terephthalate) with the aim of compensating for the lack of reactivity of the isosorbide and to reduce the coloration of the polymer. The combination of antimony oxide with a second metal (lithium-, magnesium-, or aluminium-based compounds) is investigated, leading to the discovery of innovative antimony-based bimetallic catalytic systems that exhibit a higher polymerization efficiency, even at high isosorbide contents (20%) and, in some cases, lower coloration.

A novel method for the preparation of a fluorinated aromatic diamine was investigated. This new diamine contains a fluoroalkoxy (C6F13—C2H4—O—) side chain and it was synthesised by the reaction of 1H,1H,2H,2H-perfluorooctanol with 2-(4-nitrophenoxy)-4-nitrophenol via the Mitsunobu reaction and subsequent reduction. This novel diamine was used with different dianhydrides, 4,4′-(hexafluoroisopropylidene)diphthalic anhydride (6FDA), pyromellitic dianhydride (PMDA) and benzophenonetetracarboxylic dianhydride (BTDA) to prepare polyimides by direct thermal imidization. The polyimide properties such as inherent viscosity, solubility, thermal and surface properties were investigated to illustrate the contribution of the fluoroalkoxy group that is attached to the polyimide backbone. The resulting polyimides possessed good thermal properties, the presence of the fluoroalkoxy group did not affect the thermal stability and increased the solubility in common organic solvents. The glass transition temperatures (Tg) of the fluorinated polyimides were higher than 195°C. The surface tension determined by contact angle measurements of the polyimide prepared with dianhydride 6FDA and diamine containing fluorinated alkoxy side group was 25.3 mN·m–1.