Electrospinning of polymeric composites with GRMs for different industrial applications

Electrospinning is the most common and industrially scalable technique for the production of polymeric nanofibers. Currently, nanocomposites are drawing much interest for their excellent properties in terms of flexibility, electrical conductivity and high surface area, which enhances the interaction with the surrounding environment. The objective of this thesis was the optimization of different electrospinning setups for the production of nanostructured polymeric composites using graphene-related materials as nanofillers. Such composites were obtained using different polymers as matrix (polyamide 6, polyinylidene fluoride and polylactic acid) that were selected and combined with the appropriate reinforcements based on their properties and their interest for specific applications. Moreover, this study highlighted the possibility to tune the morphology and size of the produced nanofibers by the addition of appropriate nanofillers even in low amounts. The addition of only 0.5% of GO allowed the production of smooth nanofibers with diameters up to 75% thinner (in the case of PLA) than the ones obtained from the pristine polymer. PVdF was charged with GO to produce triboelectric materials that can be exploited in a wearable nanogenerator for the conversion of human motion energy in electrical energy. The addition of GO improved the open-circuit voltage and power-output of a generator prototype by 3.5 times. Electrospun PA6 membranes were coated with rGO using a simple two-step technique to produce conductive textiles for wearable electronic applications. The sheet resistance of the produced materials was measured in approximately 500 Ω/sq and their resistance to washing and bending was successfully tested. These materials could be exploited as strain sensors or heating elements in smart textiles. PLA was co-electrospun with GO and cellulose nanofibers to produce high-surface area and porosity mats that could be exploited for the production of functionalized highly selective adsorption membranes with low pressure drops.

Application of different instrumental techniques to the selective evaluation of bio-sensible compounds in foodstuff of animal and vegetable origin

This PhD thesis describes the application of some instrumental analytical techniques suitable to the study of fundamental food products for the human diet, such as: extra virgin olive oil and dairy products. These products, widely spread in the market and with high nutritional values, are increasingly recognized healthy properties although their lipid fraction might contain some unfavorable components to the human health. The research activity has been structured in the following investigations: “Comparison of different techniques for trans fatty acids analysis” “Fatty acids analysis of outcrop milk cream samples, with particular emphasis on the content of Conjugated Linoleic Acid (CLA) and trans Fatty Acids (TFA), by using 100m high-polarity capillary column” “Evaluation of the oxidited fatty acids (OFA) content during the Parmigiano-Reggiano cheese seasoning” “Direct analysis of 4-desmethyl sterols and two dihydroxy triterpenes in saponified vegetal oils (olive oil and others) using liquid chromatography-mass spectrometry” “Quantitation of long chain poly-unsatured fatty acids (LC-PUFA) in base infant formulas by Gas Chromatography, and evaluation of the blending phases accuracy during their preparation” “Fatty acids composition of Parmigiano Reggiano cheese samples, with emphasis on trans isomers (TFA)”