This research intends to explore the mechanism behind the transformation of ethanol over basic and acid/base catalysts. The approach used was first to explore in depth the role of the MgO which is a common component of both reactions (Lebedev and Guerbet) and then to study the incorporation of Si ion and the effect on the acid/base properties of the resulting materials. Moreover, the addition of a dopant with acid/dehydrogenating properties was also explored. Further on, several catalysts were tested under the usual conditions for this reaction and characterization was made in order to understand their particular behavior. An important tool in this research was the in-situ infrared diffuse reflectance spectroscopy (DRIFTS) coupled with mass spectrometry (MS) due to the possibility that it offers to study what occurs on the catalysts surface under real working conditions. This study allowed to gain new insights on the mechanism behind the catalytic upgrading of ethanol on basic and acid/base mixed oxides, giving an alternative view of the mechanism for the Lebedev and Guerbet reactions that permitted us to discard the key role of the generally accepted intermediates and helped to explain several experimental findings not clear before.

The present study is focused on the development and improvement of sustainable catalytic processes for the synthesis of organic carbonates. In particular, the condensation reaction between carbon dioxide and several alcohols and diols has been investigated using a new generation of mesoporous nanosilicas functionalized by the insertion of amino groups on the catalyst surface. This reaction were performed in a high-pressure batch vessel (autoclave). Moreover, the carbonate interchange reaction (CIR) of the simplest linear organic carbonate, dimethyl carbonate (DMC) with several alcohols has been implemented by means of a new lab-scale reactive distillation system. In this new system, the distilled mixture is continuously passed over molecular sieves able to promote a selective adsorption of methanol (co-product of the reactions) while DMC is continuously refluxed back into the reaction batch. In this way, we were able to promote an efficient shift of the reaction equilibria toward the formation of the desired products. This system allowed us to achieve up to 90% isolated yield of pyrocatechol carbonate (PCC), a new and previously scarcely investigated carbonate. The PCC has been used as a new and more efficient carbonate source for the selective synthesis of symmetric carbonates and for the synthesis of glycerol carbonate (GlyC). GlyC has been also used as glycidol intermediate, for the condensation reaction with catechol in order to obtain the efficient synthesis of 2-hydroxymethy-1,4-benzodioxane (HMB) an important intermediate for the pharma industry. Finally, some of the synthesized carbonates were tested for the gas-phase phenol alkylation showing an interesting reactivity that could be properly modulated by changing the reaction conditions and the catalyst acid-base properties.

The aim of this thesis is to push forward the synthesis of well-defined materials containing polar monomers. The ATRP of polar monomers was investigated with the aim to obtain living and well-defined materials. Block copolymers with pre-determinable composition and unimodal distribution of molecular weight were synthesized. Furthermore, the Atom Transfer Radical Co-Polymerization of NVCL and NVP with non-polar monomers was investigated with the aim to obtain amphiphilic material with tunable polarity. The ATRP of vinyl acetate (VAc), which was poorly optimized, was studied trying to obtain poly(VAc) with low polydispersity (<1.25), pre-determinable molecular weight and living character. The optimization of the ATRP of VAc and the synthesis of several block copolymers, synthesized in presence of different experimental conditions, can significantly expand the field of materials and applications of poly(VAc) and poly(vinyl alcohol)-based products. Moreover, the synthesis of pH and temperature polymers was investigated with the aim to obtain products suitable for the development of drug-delivery systems which can be applied in anti-cancer applications. For this purpose Pluronic F127, which is thermosensitive, and poly(ethylene glycol)s were modified with pH poly[2-(N,N-dimethylamino)ethyl methacrylate] (PDMAEMA), poly[2-(N,N-diethylamino)ethyl methacrylate] (PDEAEMA) and poly[2-(N,N-diisopropylamino)ethyl methacrylate] (PDIAEMA). The methacrylic moieties have different pKa, and they give to the synthesized materials the desired pH responsiveness. The gelation behavior of the obtained products was investigated by rheological measurements; the dimension of the polymeric aggregates in water solutions at different pH was studied by DLS and the drug-incorporation as a function of pH was determined in systems with stable pH and in systems in which the pH was decreased progressively. All the cited investigation allowed to well-characterized the behavior and the structure of polymeric aggregates in water solution and they also allowed to determine their pH and temperature responsiveness.

During my PhD I carried out three main research works, which are described in this thesis. The topics of my research were dealt with the development of more sustainable processes through the exploitation of renewable sources and the replacement of hazardous chemicals with safer ones. Two of the three research topics I carried out dealt with ethanol as a renewable source for the development of more sustainable processes. Another research topic concerned isobutene alkylation with methanol, as a substitute for formaldehyde. First research project was regarding ethanol transformation over V-based catalysts. Fe/V and Cu/V mixed oxides were tested as catalysts for the transformation of ethanol both in aerobic and anaerobic conditions. Both catalysts were active in ethanol dehydrogenation to acetaldehyde. Anyway the presence of Fe or Cu had an influence on catalytic performance. The reason of these different behaviours were investigated by means of characterization techniques. Another research work, regarding ethanol as raw material, was carried out during my stage at the Lieibniz Institute für Katalyse (Germany), under the supervision of Dr. Habil. Evgenii Kondratenko. The research topic dealt with ethanol conversion to H2 and CO2 by means of partial oxidation carried out over supported Pt, Rh and Ru nanoparticles. The greater part of the research work dealt with isobutene alkylation with methanol, in place of formaldehyde, for the production of isoprene via the Prins reaction. The reaction was carried out over different metal phosphates. Main products were isoprene, 2-methylbutenes and dimethyl ether. An investigation on the reaction scheme showed that these products are kinetically primary compounds. Data and investigations shown in this thesis probably will not lead soon to the development of new chemical processes, but they enrich that scientific background that is the pool from which it is possible to design a more sustainable industrial chemistry.

Nicotinic acid (niacin) is an important vitamin of the B group, with an annual production close to 40,000 tons. It is used in medicine, food industry, agriculture and in production of cosmetics. Older industrial processes have drawbacks such as a low atomic efficiency and the use of toxic catalysts or stoichiometric oxidants. Several studies were carried out during latest years on new technologies for the synthesis of niacin and nicotinate precursors, such as 3-picoline and pyridine-3-nitrile. This thesis reports about the results of three different research projects; the first was aimed at the study of the one-step production of pyridine-3-nitrile starting from 2-methylglutaronitrile, the second at acetaldehyde/acetonitrile condensation for 3-picoline synthesis, and the third at investigating the reactivity of supported vanadium oxide catalysts for the direct gas-phase oxidation of 3-picoline with air; this process would be more sustainable compared to both older ones and some of those currently used for niacin production. For the first two research projects, a catalysts screening was carried out; however, results were not satisfactory. The third project involved the preparation, characterisation and reactivity testing of different zirconia-supported V2O5 catalysts. The effect of parameters, such as the Vanadium oxide loading and specific surface area, on catalytic performance were studied. Operative conditions such as temperature, contact time and feed composition were optimized. Yields to nicotinic acid close to the best ones reported in the literature were achieved; moreover, catalysts based on V2O5/ZrO2 were found to be remarkably active. Catalysts were characterized by means of XRD and in-situ Raman spectroscopy in the aim of finding correlations between catalytic performances and physic-chemical properties. In some cases, ZrV2O7 formed during the reaction. Vanadyl-pyrophosphate was also tested as the catalyst for 3-picoline oxidation, but its performance was lower compared to that one shown by V2O5/ZrO2.

In this dissertation, we firstly developed a new method to evaluate the exfoliation results of Graphene and other 2D materials (Graphene Oxide, Boron Nitride).This was essential to understand the fundamental processes behind the production of 2D materials. Additionally, that helped us to understand the production development of 2D-based composite materials and bio- compatible materials, such as gelatin fibers. We evaluated the processed 2D nanomaterials with commonly used characterization techniques used in the scientific and industrial world, which are the Atomic Force Microscope. Furthermore, we developed this method by using Fluorescence Optical Microscopy (FOM), Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM). Based on AFM analysis of thousands samples, the exfoliation of 2D nanomaterials, like the distributions recognized in the fields of biology, astronomy and mineralogy. We demonstrated a new way to produce stable graphene solutions in low boiling point solvents and how the exfoliated material can interpret into polymer surface such as Polyvinylchloride (PVC) and natural rubber. Overall, the uniqueness of this work is that we developed a new method that has not been studied before and gives the opportunity to materials scientists that are researching on the growing field of Graphene and other 2D materials to have a method in order to control, quantify and evaluate the exfoliation results of nanomaterials that are produced through the most well-known methods of liquid phase exfoliation and ball milling, both of which are applied in scientific and industrial level. Thus, the results presented in this work may offer insight into the polymer composites where the size and shape of nanosheets can be rationally optimized.

Geopolymers are synthetic materials formed by alkali-activation of aluminosilicate particles. They have attracted increasing attention as sustainable materials, being obtained from different raw materials, including industrial by-products, and by production processes at low temperature. Thanks to the good properties showed by these materials (thermal stability, fire-resistance, etc.), and the intrinsic mesoporosity, geopolymers have been studied as new materials for applications in many industrially relevant fields. To achieve full advantage of their porous structure, it is necessary to control its formation. The geopolymer production process in aqueous medium allows to tailor the porosity from nanometric to millimetric range since water acts as pore former. Moreover, ultra-macroporosity may be induced in the materials exploiting different techniques, commonly used for the production of porous ceramics, determining the possibility to obtain materials with different architectures, pore size and shape, etc. Hierarchical pore systems, where the mesopores of the geopolymer skeletal materials are directly connected to macro- and finally to ultra-macropores, may be constructed in this way. The main goal of this research project was to investigate the use of different process techniques applied to geopolymer matrices to generate porous structures characterized by peculiar porosities able to determine specific properties and functionalize the materials. In detail, the porosity was induced by direct foaming or addition of lightweight aggregates. Furthermore, geopolymers with main unidirectional anisotropic macropores were produced, for the first time, using a freeze-casting technique. All the materials produced were deeply investigated to optimize the production processes and evaluate the final properties, many of which arising from the intrinsic and induced porosity generated, in order to address the materials for potential applications as, for example, thermal insulating panels or heat transfer devices.

The main topics explored in this thesis regard the synthesis of some new polythiophenes for the preparation of efficient and stable polymeric solar cell with the bulk heterojunction architecture and the study of the mechanism involved in the radical emulsion polymerization of VDF/HFP to obtain copolymers with an optimized thermal and mechanical behavior.

Thiophene based oligomers and polymers are of great current interest from a scientific and technological point of view for their numerous properties: they are electroactive, fluorescent, chemically stable and allow a great diversity in molecular structures and a fine tuning of functional characteristics. They display ‘plasticity’ in adapting their geometry to the environment in the solid state and in creating supramolecular architectures by self-organization. Moreover, they have the capability to finely interact with biologically relevant molecules such as intracellular proteins. All these properties allow a large number of different applications in fields such as organic electronics and bioimaging which prompted the development of highly efficient and ‘user friendly’ synthetic approaches for their preparation. We have synthesized unprecedented classes of functional thiophene based materials by employing enabling technologies such as microwave and ultrasound irradiation in order to obtain oligo and polythiophenes in very pure form and high yields. Preparing oligo- and polythiophenes in very pure form by means of rapid and environmentally friendly procedures is crucial for application of these compounds in materials chemistry as semiconductor and fluorescent compounds for electronic and optoelectronic devices as well as for application in cell imaging and monitoring of intracellular processes.

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