RESUMO
The synthesis and characterization of amphiphilic polymers bearing gluconolactone moieties has been described. In a first step, an unprotected glycomonomer 2-[({[4-(d-gluconamid-N-yl)butyl]amino}carbonyl)oxy]ethyl acrylate, HEAG, has been synthesized. Posterior, this glycomonomer has been copolymerized with methyl methacrylate at different compositions and the kinetic behavior has been also studied calculating the monomer reactivity ratios by Kelen-Tüdös extended equation. In addition, the long side-chain crystalline behavior of these carbohydrate-based copolymers with high composition of glycomonomer has been examined by using conventional and modulated differential scanning calorimetry and X-ray diffraction measurements. At the same time, the phase separation behavior of carbohydrate-based copolymers with lower HEAG content has been determined by their glass transition temperature measurements. Finally, the thermal stability of all these amphiphilic copolymers has been evaluated by thermogravimetric analysis.
RESUMO
Optimization of the interfacial agent content in biocidal titania-isotactic polypropylene nanocomposites is performed by evaluating their structural, thermal, optical, and biocidal properties. The balance between the photochemistry (photokilling) behavior and the thermal properties is achieved in the nanocomposites with an incorporation of 2 wt.% in inorganic nanoparticles (Tio2) using a compatibilizer content ranging from 50 to 80 wt.% with respect to the titania amount