New bio-based polymers: from synthesis to characterization

The environmental problems caused by human activity are one of the main themes of debate of the last Century. As regard plastics, the use of non-renewable sources together with the accumulation of waste in natural habitats are causing serious pollution problems. For this reason, a continuously growing interest is recorded around sustainable materials, potential candidate for the replacement of traditional recalcitrant plastics. Promising results have been obtained with biopolymers, in particular with the class of biopolyesters. Their potential biodegradability and biobased nature is particularly interesting mainly for food packaging, where the multilayer systems normally used and the contamination by organic matter create severe recycling limits. In this framework, the present research has been conducted with the aim of synthetizing, modifying and characterizing biopolymers for food packaging application. New bioplastics based on monomers derived from renewable resources were successfully synthetized by two-step melt polycondensation and chain extension reaction following the “Green chemistry” principles. Moreover, well-known biopolyesters have been modified by blending or copolymerization, both resulting effective techniques to ad hoc tune the polymer final characteristics. The materials obtained have been processed and characterized from the chemical, structural, thermal and mechanical point of view; more specific characterizations as compostability tests, surface hydrophilicity film evaluation and barrier property measurements were conducted.

Copolimeri statistici di p-vinilfenolo e metilmetacrilato per la compatibilizzazione di miscele polimeriche

I biopolimeri, al centro dell’attenzione del mondo scientifico, non sempre presentano caratteristiche paragonabili a quelle dei polimeri tradizionali quindi una tecnica molto diffusa che si pone l’obiettivo di migliorare le loro proprietà è il blending. Tuttavia, dalla miscelazione due polimeri possono risultare miscibili, parzialmente miscibili o immiscibili. Nel caso in cui fossero immiscibili una pratica comune è quella di aggiungere un compatibilizzante con l’obiettivo di ridurre le tensioni interfacciali, stabilizzare la morfologia e migliorare le proprietà. Nello specifico PLA e PCL, immiscibili tra loro, presentano proprietà notevoli quindi il nostro contributo si inserisce in quest’ambito con l’obiettivo di progettare e sintetizzare nuovi compatibilizzanti, copolimeri statistici, composti da due unità monomeriche diverse da quelle che costituiscono il blend, tuttavia affini ognuna ad una delle due fasi. Al fine di studiare le loro potenziali attività compatibilizzanti i copolimeri sono stati aggiunti al blend PLA/PCL e sono state studiate le proprietà risultanti mediante analisi termiche, strutturali e morfologiche.

Design of luminescent metal complexes for polymer science

The program of my PhD studies has been dealing with the investigation of the research outcomes that may result from the use of luminescent Iridium(III) cyclometalated complexes in the field of polymer science. In particular, my activity has been focused on exploring two main applicative contexts, i.e. Ir(III) complexes for preparing polymers and in combination with polymers. In the first part, a new set of luminescent Ir(III) complexes was exploited as photocatalysts for light-assisted atom transfer radical polymerization of methyl methacrylate. The decoration of both cyclometalated and ancillary ligands with sp3 hybridized nitrogen substituents together with the use of specific counterions, imparted suitable photophysical and redox properties for an efficient photocatalyzed process. The second part has been focused on the employment of Ir(III) tetrazole complexes as phosphorescent dyes in polymeric materials. Colourless luminescent solar concentrators were prepared blending two Ir(III) cyclometalates with acrylate polymers. Their performances were investigated, leading to promising outcomes comparable, or superior, to those obtained from colourless LSCs based on organic fluorophores. As a complementary approach, Ir(III) complexes were covalently linked to polymers in the side chain, to obtain a new class of metallopolymers. To this extent, a bifunctional tetrazolate molecule, equipped with a coordination site and a polymerizable unit, was designed. The photophysical properties of the resultant luminescent polymeric films were discussed. In the end, an additional project involving both polymers and metal compounds was carried out during my experience as a visiting PhD student at Humboldt – University of Berlin. Polystyrene and polyethylene glycol -based ion-exchange resins were functionalized with peptides through a ligation pathway, for the selective chelation of Copper(II) in aqueous solutions. The coordinating capability of the materials towards Cu2+ ions was tested by ICP-MS analysis. The resins strategically modified with ion-selective peptides, may be exploited in the preparation of water-processing devices.

Serverless middlewares to integrate heterogeneous and distributed services in cloud continuum environments

The application of modern ICT technologies is radically changing many fields pushing toward more open and dynamic value chains fostering the cooperation and integration of many connected partners, sensors, and devices. As a valuable example, the emerging Smart Tourism field derived from the application of ICT to Tourism so to create richer and more integrated experiences, making them more accessible and sustainable. From a technological viewpoint, a recurring challenge in these decentralized environments is the integration of heterogeneous services and data spanning multiple administrative domains, each possibly applying different security/privacy policies, device and process control mechanisms, service access, and provisioning schemes, etc. The distribution and heterogeneity of those sources exacerbate the complexity in the development of integrating solutions with consequent high effort and costs for partners seeking them. Taking a step towards addressing these issues, we propose APERTO, a decentralized and distributed architecture that aims at facilitating the blending of data and services. At its core, APERTO relies on APERTO FaaS, a Serverless platform allowing fast prototyping of the business logic, lowering the barrier of entry and development costs to newcomers, (zero) fine-grained scaling of resources servicing end-users, and reduced management overhead. APERTO FaaS infrastructure is based on asynchronous and transparent communications between the components of the architecture, allowing the development of optimized solutions that exploit the peculiarities of distributed and heterogeneous environments. In particular, APERTO addresses the provisioning of scalable and cost-efficient mechanisms targeting: i) function composition allowing the definition of complex workloads from simple, ready-to-use functions, enabling smarter management of complex tasks and improved multiplexing capabilities; ii) the creation of end-to-end differentiated QoS slices minimizing interfaces among application/service running on a shared infrastructure; i) an abstraction providing uniform and optimized access to heterogeneous data sources, iv) a decentralized approach for the verification of access rights to resources.

New biomaterials for packaging: a green approach to biopolymers and biocomposites

The impellent global environmental issues related to plastic materials can be addressed by following two different approaches: i) the development of synthetic strategies towards novel bio-based polymers, deriving from biomasses and thus identifiable as CO2-neutral materials, and ii) the development of new plastic materials, such as biocomposites, which are bio-based and biodegradable and therefore able to counteract the accumulation of plastic waste. In this framework, this dissertation presents extensive research efforts have been devoted to the synthesis and characterization of polyesters based on various bio-based monomers, including ω-pentadecalactone, vanillic acid, 2,5-furan dicarboxylic acid, and 5-hydroxymethylfurfural. With the aim of achieving high molecular weight polyesters, different synthetic strategies have been used as melt polycondensation, enzymatic polymerization, ring-opening polymerization and chain extension reaction. In particular, poly(ethylene vanillate) (PEV), poly(ω-pentadecalactone) (PPDL), poly(ethylene vanillate-co-pentadecalactone) (P(EV-co-PDL)), poly(2-hydroxymethyl 5-furancarboxylate) (PHMF), poly(ethylene 2,5-furandicarboxylate) (PEF) with different amount of diethylene glycol (DEG) unit amount, poly(propylene 2,5-furandicarboxylate) (PPF), poly(hexamethylene 2,5-furandicarboxylate), (PHF) have been prepared and extensively characterized. To improve the lacks of poly(hydroxybutyrate-co-valerate) (PHBV), its minimal formulations with natural additives and its blending with medium chain length PHAs (mcl-PHAs) have been tested. Additionally, this dissertation presents new biocomposites based on polylactic acid (PLA), poly(butylene succinate) (PBS), and PHBV, which are polymers both bio-based and biodegradable. To maintain their biodegradability only bio-fillers have been taken into account as reinforcing agents. Moreover, the commitment to sustainability has further limited the selection and led to the exclusive use of agricultural waste as fillers. Detailly, biocomposites have been obtained and discussed by using the following materials: PLA and agro-wastes like tree pruning, potato peels, and hay leftovers; PBS and exhausted non-compliant coffee green beans; PHBV and industrial starch extraction residues.

Integrare gli approcci all'innovazione Data Science e Design Thinking: analisi teorica e applicazione al caso della sanità parmense

Nel panorama aziendale odierno, risulta essere di fondamentale importanza la capacità, da parte di un’azienda o di una società di servizi, di orientare in modo programmatico la propria innovazione in modo tale da poter essere competitivi sul mercato. In molti casi, questo e significa investire una cospicua somma di denaro in progetti che andranno a migliorare aspetti essenziali del prodotto o del servizio e che avranno un importante impatto sulla trasformazione digitale dell’azienda. Lo studio che viene proposto riguarda in particolar modo due approcci che sono tipicamente in antitesi tra loro proprio per il fatto che si basano su due tipologie di dati differenti, i Big Data e i Thick Data. I due approcci sono rispettivamente il Data Science e il Design Thinking. Nel corso dei seguenti capitoli, dopo aver definito gli approcci di Design Thinking e Data Science, verrà definito il concetto di blending e la problematica che ruota attorno all’intersezione dei due metodi di innovazione. Per mettere in evidenza i diversi aspetti che riguardano la tematica, verranno riportati anche casi di aziende che hanno integrato i due approcci nei loro processi di innovazione, ottenendo importanti risultati. In particolar modo verrà riportato il lavoro di ricerca svolto dall’autore riguardo l'esame, la classificazione e l'analisi della letteratura esistente all'intersezione dell'innovazione guidata dai dati e dal pensiero progettuale. Infine viene riportato un caso aziendale che è stato condotto presso la realtà ospedaliero-sanitaria di Parma in cui, a fronte di una problematica relativa al rapporto tra clinici dell’ospedale e clinici del territorio, si è progettato un sistema innovativo attraverso l’utilizzo del Design Thinking. Inoltre, si cercherà di sviluppare un’analisi critica di tipo “what-if” al fine di elaborare un possibile scenario di integrazione di metodi o tecniche provenienti anche dal mondo del Data Science e applicarlo al caso studio in oggetto.