Cellulose triacetate (CTA) and sol−gel synthesized TiO 2 nanoparticles were used to develop and characterize novel nanocomposites modified also with poly(ethylene oxide-bpropylene oxide-b-ethylene oxide) (EPE) triblock copolymer. The designed nanocomposites presented UV-shielding properties, being the protection higher at high sol−gel content, with suitable surface finish and high transparency even with 20 vol % sol−gel content. The DSC results showed a decrease of the T g and T m of the CTA phase, indicating a partial miscibility between the nanocomposite components. The AFM measurement indicated that the addition of EPE triblock copolymer led to the nanostructuration of the CTA matrix, allowing to control the dispersion of the TiO 2 nanoparticles since the PEO block acted as surfactant for the TiO 2 nanoparticles preventing their aggregation. The EFM measurement proved that the TiO 2 nanoparticles embedded in the CTA or the PEO block/CTA matrix maintained their conductive properties. Moreover, the TiO 2 nanoparticles acted as reinforcement improving the Young's modulus of nanocomposites. The designed nanocomposites presented interesting properties and surface appearance to design a wide variety of products.

No abstract

No abstract

A biobased diglycidyl ether of vanillin (DGEVA) epoxy resin was nanostructured by poly(ethylene oxide-b-propylene oxide-b-ethylene oxide) (PEO-PPO-PEO) triblock copolymer. Due to the miscibility/immiscibility properties of the triblock copolymer in DGEVA resin, different morphologies were obtained depending on the triblock copolymer amount. A hexagonally packed cylinder morphology was kept until reaching 30 wt% of PEO-PPO-PEO content, while a more complex three-phase morphology was obtained for 50 wt%, in which large worm-like PPO domains appear surrounded by two different phases, one of them rich in PEO and another phase rich in cured DGEVA. UV-vis measurements show that the transmittance is reduced with the increase in triblock copolymer content, especially at 50 wt%, probably due to the presence of PEO crystals detected by calorimetry.

No abstract