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Polymer-based scintillator composites have been produced by combining polystyrene (PS) and GdO:Eu scintillator nanoparticles. Polystyrene has been used since it is a flexible and stable binder matrix, resistant to thermal and light deterioration and with suitable optical properties. GdO:Eu has been selected as scintillator material due to its wide band gap, high density and visible light yield. The optical, thermal and electrical characteristics of the composites were studied as a function of filler content, together with their performance as scintillator material. Additionally 1 wt.% of 2,5-diphenyloxazole (PPO) and 0.01 wt.% of 1,4 di[2-(5phenyloxazolyl)]benzene (POPOP) were introduced in the polymer matrix in order to strongly improve light yield, i.e., the measured intensity of the output visible radiation, under X-ray irradiation. Increasing scintillator filler concentration (from 0.25 to 7.5 wt.%) increases scintillator light yield and decreases the optical transparency of the composite. The addition of PPO and POPOP strongly increased the overall transduction performance of the composite due to specific absorption and re-emission processes. It is thus shown that GdO:Eu/PPO/POPOP/PS composites with 0.25 wt.% of scintillator content with fluorescence molecules are suitable for the development of innovative large-area X-ray radiation detectors with huge demand from the industries. [ABSTRACT FROM AUTHOR]

Poly(vinylidene fluoride-trifluoroethylene), P(VDF-TrFE), electrospun membranes were obtained from a mixture of dimethylformamide (DMF) and methylethylketone (MEK) solvents. The inclusion of MEK to the solvent system promotes a faster solvent evaporation allowing complete polymer crystallization in the jet traveling between the tip and the grounded collector. The main electrospinning processing parameters were systematically changed to study their influence on fiber dimensions and distribution. Applied voltage and inner needle diameter do not have a large influence on the electrospun fiber average diameter but do on the fiber diameter distribution. On the other hand, increasing the distance between the needle tip and the collector gives origin to fibers with larger average diameter. Independently of the processing conditions, all membranes are produced in the electroactive phase of the polymer. Further, MC-3T3-E1 cell adhesion is not inhibited by the fiber membrane preparation, showing their potential use for biomedical applications. [ABSTRACT FROM AUTHOR]