PianodiAttività,ProgettodiRicercaePianodiFormazione
Assegnocollegatoal progetto PRIN 2015 “Smart composite laminates” cod. 2015RT8Y45
TITOLO:
PREPARAZIONE, CARATTERIZZAZIONE E SVILUPPO DI NUOVI MATERIALI COMPOSITI CON NANOFIBRE PIEZOELETTRICHE
PREPARATION, CHARACTERIZATION AND DEVELOPMENT OF NEW COMPOSITE MATERIALS WITH PIEZOELECTRIC NANOFIBERS
ATTIVITÀ DI RICERCA
Among the different classes of composite materials, fiber reinforced polymers (FRP) are to date the most popular and perhaps the most versatile ones. FRP composites can be considered as ‘‘engineered’’ materials comprised by a polymer matrix in which the reinforcing micrometric fibers are embedded. FRP composites are commonly designed with the primary aim of obtaining mechanical properties tailored for the application. Completely different purposes are reserved to the so-called ‘smart’ materials, whose design is not meant to optimize the mechanical properties.
Piezoelectric materials found applications both exploiting the so-called direct and inverse effects. The direct effect relates to the ability to generate an electrical charge from a mechanical strain, which associates to sensing and energy harvesting applications. This effect can be further be exploited for vibration control as the energy harvesting will contemporarily mitigate the vibrations, with positive effect on the fatigue life of the component. The reverse piezoelectric effect instead refers to the ability to generate a mechanical deformation from an electrical input, fostering the use of piezoelectrics for actuating purposes. Ceramic and polymeric piezoelectric materials can be used in these applications. The formers are brittle and cannot be realized in small films but show a large piezoelectric effect, the latters are more flexible and lightweight, but they have limited electro-mechanical conversion rates. Recently, members of the “Smart composite laminates” (cod. 2015RT8Y45) PRIN 2015 projectresearch team developed an innovative piezoelectric fibers production technique through polymeric electrospinning, which is found to significantly improve the electro-mechanical conversion rate of polymeric-based piezoelectrics. Further, electrospun membranes can be easily manufactured in different shapes, with random or aligned fiber patterns, in the emerging application field of wearable piezoelectric textiles.
In this context, the nanostructured fibrous piezoelectric polymers will be produced through the electrospinning process The copolymer polyvinylidenefluoridetrifluoroethylene (PVdFTrFE) as well as similar commercial copolymers will be utilized as raw material due to their intrinsic piezoelectric behavior which can be enhanced by increasing the beta phase due to electrical poling and mechanical stretching of the polymeric jet during the electrospinning process. The researcher will initially optimise the manufacturing methodology to enhance quality and standardization of the final electrospinned mat. The chemical, thermal and thermomechanical properties will be studied in the Prof. Giorgini’s unit.
A first outcome from this research will be the development of practical guidelines for the manufacturing process of electrospinned piezoelectric nanofibers as a function of the desired thickness and morphology in general.
Then, the project will move to the chemical optimization of the polymeric resins and curing cycle optimization to maximize the (thermo)mechanical properties of the final composites. In particular, the researcher will conductthe study with the main objective of maximizing the adhesion between nanofibers and matrix.
The cure cycle of the resins and the exothermic behaviour of the fast polymerization reaction will be optimized through DSC studies.
Tominimize the overall cost of the project and contemporarily leverage the possible final utilizationof the envisioned structure in industrial applications the analysis will not only limit to epoxy,vinylester,cyanate esterandpolyesterbased resins, but new biopolymers resins will be investigated.
In turn, only compatible reinforceswill be utilized within this project: polyaramidic (Nomex and Kevlar type), glass and carbonfibers.
PIANODIFORMAZIONE
Ilpianoformativoprevedelostudiodellasintesi,caratterizzazioneepreparazionedimaterialicompositiabasepolimericael’approfondimentodellemetodologiedicaratterizzazionedellematerieplasticheutilizzateedellelorointerazioniconilrinforzantespecifico.
Inparticolare,verrannopreparatechimicamenteecaratterizzatestrutturalmente,termicamenteemeccanicamentenuoveresinepolimericheenuoveresinefunzionalizzate.
Questeresinesarannoutilizzateperlapreparazioneconadeguatirinforzidiprovinidicompositochesarannocaratterizzatiinmanierachimico-fisica,meccanicaediresistenzaneltempoeasollecitazionitermiche,conparticolareattenzionealleinterazioniinterfacciali e alla cinetica di reticolazione.
Saranno preparate e caratterizzate nanofibre piezoelettriche che saranno poi incorporate in provini di materiale composito.
Sarannopreparatiprototipidimaterialecompositopolimericochesarannopoitestatisperimentalmente.
Sarannoeffettuatecorrelazioniperdefinirelerelazionistruttura-proprietàdellematerieplasticheedeimanufattifinali.
Questistudipotrannoessereapplicabiliadiversealtretipologiedimanufattiutilizzabiliinaltriambititecnologici.
L’assegnista parteciperà ad almeno una Scuola e almeno ad un Convegno nell’ambito della Scienza e tecnologia dei materiali polimerici e dei compositi in generale.
L’assegnista acquisirà capacità espositive e di scrittura di articoli scientifici.