In this study fabrication and characterization of transparent nanostructured composite films based on cellulose triacetate (CTA) and poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide) (EPE) triblock copolymer were presented. The effect of the addition of EPE triblock copolymer on the thermal stability, morphology, and mechanical properties of cellulose triacetate films was investigated. The triblock EPE was chosen since PEO blocks interact favorably with CTA, whereas, PPO blocks remain immiscible which provokes a microphase separation. This allows to obtain EPE/CTA composite films with ordered microphase-separated structures where PPO spherical microdomains are well-dispersed in PEO/CTA matrix by simple solvent-evaporation process. During this process, PEO block chains selectively interact with CTA by strong interpolymer hydrogen-bonding while PPO block microseparated. The addition even 40wt% of EPE leads to nanostructured EPE/CTA composite. The cytotoxicity assay of CTA and EPE/CTA composite films confirm non-toxic character of designed transparent nanostructured composites based on sustainable matrices.

An electrospinning technique is used to obtain poly(ethylene-b-ethylene oxide) block copolymer (PE-b-PEO) fibers. Optimization of the electrospinning processing-window is carried out by varying the concentration of the block copolymer solution and playing with three different electrospinning parameters, applied voltage, solvent and block copolymer solution flow rate. The influence of the concentration of the block copolymer solution over the length and diameter of the fibers is mainly studied and results indicate that the optimum conditions to fabricate PE-b-PEO block copolymer fibers are concentrations between 45 and 47 wt% of PE-b-PEO block copolymer and chloroform/DMF mixture ratio of 4:1 and 5:1. Moreover, low solvent and block copolymer solution flow rates led to the longest and widest fibers. Hybrid fibers are also fabricated modifying PE-b-PEO block copolymer fibers with low molecular weight N-(4-ethoxybenzylidene)24butylaniline (EBBA) nematic liquid crystal using coaxial electrospinning technique. The morphology of the fabricated fibers is investigated from micro to nanoscale. Atomic force microscopy (AFM) results show selforganization of investigated PE-b-PEO and hybrid PE-b-PEO/EBBA fibers on the nanometric scale, which make them interesting from the point of view of novel applications as template materials.

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