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L’invenzione riguarda un impianto e un metodo per il recupero di fibre di carbonio o di vetro da materiali compositi nei quali dette fibre sono racchiuse in una matrice polimerica. suddetti materiali compositi possono provenire da scarti prodotti in diversi stadi di lavorazione industriale e/o da manufatti giunti al termine del loro ciclo di vita.

Un impianto (1) per il recupero di fibre di carbonio o di vetro da materiali compositi comprendenti dette fibre in una matrice polimerica comprende un forno a tunnel (2) lungo il quale detti materiali vengono trasportati all’interno di contenitori (6), in cui detto forno a tunnel comprende una zona di pirolisi (3), nella quale detti materiali compositi sono assoggettati a un processo di pirolisi in un’atmosfera priva di ossigeno, una zona di gassificazione (3) nella quale detti materiali sono sottoposti a un processo di combustione in presenza di ossigeno, e una zona intermedia di separazione (5), posta tra la zona di pirolisi (3) e la zona di gassificazione (4), nella quale è prevista una pluralità secondi dispositivi iniettori (23) per immettere azoto in detta zona intermedia (5), in modo da impedire che l’atmosfera della zona di pirolisi (2) entri in contatto con l’atmosfera della zona di gassificazione (3).

This study provides an overview of the effects of prolonged acid attack on the surface of PTFE gaskets, assessed using Fourier Transform Infrared Spectroscopy (FT-IR), Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). The PTFE analysed originates from two manufacturers in form of Teflon adhesive tapes, used as gaskets in an ultrasonic tyre moulds cleaning plant (UMCS). The gaskets were exposed to various acid baths, temperature and ultrasonic waves, and shown anomalous damage and surface degradation in a relatively short operation time. The analyses here reported have been aimed at investigating this unusual behaviour. PTFE samples have been treated with different acid mixes to evaluate possible different aging effects. Both surface and core have been analysed after aging, providing evidence of the degradation phenomena. In particular, different acid treatments have highlighted different response of PTFE and differences among manufacturers.

The present research work was targeted at evaluating alternative additives to traditional ones used in the industry of plasticized PVC synthetic leathers for the automotive interior industry. In fact, safety and performance are the driving force in this field of application.. In fact, the manufacturing of these materials still sees the presence of additives (i.e. phthalates plasticizers, antimony trioxide, azodicarbonamide) which pose more than an issues regarding both human health and the environment. More than 70 alternative additive, belonging to both fossil–fuel and renewable feedstock, have been selected, characterized and tested inside standard and modified plasticized PVC formulations. Moreover, novel additives as organic modified nanoclays, have been evaluated for the design of innovative high-performance synthetic leathers. An innovative dispersion technique for these nano–additives has been ideated and tuned. All of the obtained samples have been tested in plasticized PVC formulations, and the imparted properties evaluated by means of analyses typical of the automotive industry. Results allowed to identify several additives that performs better than their respective traditionally used counterparts. Finally, an economic evaluation has been made in order to verify the economic sustainability related to the use of these innovative additives.

This paper investigates the effect of a prolonged acid attack on the surface of PTFE by Fourier Transform Infrared Spectroscopy (FT-IR), Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). PTFE is a very non-reactive polymer, partly due to the strength of carbon–fluorine bonds, and for this reason it is often used in containers and pipework parts in contact with reactive and corrosive chemicals. The PTFE under analysis is commercialized by two manufacturers in form of Teflon adhesive tapes. These tapes are used as gaskets in a tyre moulds cleaning plant, based on different acid baths and ultrasonic waves. In particular, PTFE gaskets show anomalous phenomena of surface degradation in a relatively short operation time. Nevertheless, even considering the combined effect of ultrasonic waves, temperature, humidity and acid attack, PTFE properties nominally exclude the risk of the extreme erosion phenomena as observed. The present experimental research aim at investigating this contradiction. In this study PTFE samples have been treated with different mixes of acids, in order to investigate the different aging effects. The infrared and thermal analysis has permitted the characterization of PTFE surface and core properties after acid attack, providing evidence of the degradation phenomena. In particular, the different acid treatments adopted for the aging of gaskets have highlighted not only the different response of the PTFE matrix, but also differences between manufacturers.

Osservazioni condotte su impianti innovativi per la pulizia degli stampi utilizzati nella formatura dei pneumatici hanno messo in evidenza come le guarnizioni commerciali in teflon (PTFE) presentano un fenomeno di degrado imprevisto, non compatibile con le condizioni nominali di impiego e che lasciano intuire la presenza di fenomeni complessi. Si tratta di impianti che consentono la pulizia di stampi, quantunque complessi, attraverso la loro immersione in vasche di lavaggio e l’azione combinata di ultrasuoni, prodotti chimici, temperatura ed agitazione del liquido. La sovrapposizione dei diversi effetti fisici e chimici crea una situazione di forte stress chimico-meccanico su tutta la struttura di impianto, compresi gli elementi di connessione e contenimento. Alcune fuoriuscite di liquido, osservate durante il funzionamento degli impianti anche dopo un periodo di funzionamento relativamente breve, hanno concentrato l’attenzione sulle guarnizioni. Queste sono state appositamente sottoposte a degradazione controllata e successiva caratterizzazione sperimentale per investigare meglio la situazione. In particolare, questo studio descrive le condizioni di degradazione del teflon e riporta i risultati ottenuti mediante analisi spettroscopia infrarossa (FT-IR), calorimetria differenziale a scansione (DSC) e analisi termogravimetrica (TGA) in funzione del processo di degradazione Abstract This paper describes the accelerate aging tests used for investigating the surface alteration of PTFE gaskets commercialized by two alternative producers. These gaskets are installed in modern process plants where tires moulds are cleaned by a multistage ultrasonic process. Their surface degrades inexplicably under ordinary operative conditions after a relatively short period. Even if these gaskets are exposed to a combination of ultrasonic waves, temperature, humidity and acid attack, the PTFE properties of resistance nominally exclude the possibility of severe erosion phenomena as highlighted during the real utilization. A possible explanation could be represented by the presence of unexpected chemical compounds emerging from the disaggregation of highly reacting elements from the tire composition.. Thus, the experimental characterization of PTFE properties has to follow an appropriate accelerated aging, aiming at actuating the specific mechanics of wearing as in industrial use.

This work aims at demonstrating, at a pilot plant scale, the potential of the pyro-gasification process to produce carbon fibers (CF) as secondary raw materials. The solid residue obtained upon pyrolysis of CFRP was characterized and oxidized, applying different process conditions to provide clean fibers. The same process was applied to virgin fibers, thus highlighting the protective action that char provides to CF during the oxidation step. The recovered fibers were used to produce new short fiber composites which, upon optimization of the mixing and curing conditions, were competitive with the performance of pristine fibers composites. Indeed, the oxidation leaves an oxygen rich surface which positively interacts with the epoxy resin, thus promoting adhesion without the requirement of an additional sizing process after the CFs recycling. These results provided sufficient validation of the recovered CF quality, thus leading to the scale up of the process to produce an integrated pyro-gasification semi—industrial plant.

Glass fiber-reinforced polyester composite (GFRPs) scraps from manufacturing of polyester laminates were pyrolyzed at 500, 550 and 600°C in an 70 Kg innovative batch pilot plant that processes whole parts. The presence of a hydraulic guard guarantees the safety of the process. The influence of the maximum process temperature on yields and chemical-physical properties of pyrolysis products was investigated: the oil fraction was analysed by GC-MS, Viscometer and XRF, while the gas fraction was monitored online during the entire pyrolysis process by µ-GC. Substantial fractions of methane (20.7 vol %) and hydrogen (11.5 vol %) were produced. The solid residue (glass fibers covered by a thin carbonaceous layer) underwent an oxidative process at 500 and 600°C at different residence times to provide clean glass fibers free of organic residues. The effects of both pyrolysis and oxidative step on the glass fibers, obtained in different process conditions, were evaluated by SEM and Raman spectroscopy.

Nanoclays (NCs), both organically modified (OMNCs) and purely inorganic, have been evaluated as performance enabling fillers for innovative and high-performance plasticized PVC (pPVC) synthetic leathers (SLs). First, a novel dispersion technology for nanoclays in plastisols has been developed and tuned, modifying and improving different procedures used in Vulcaflex SpA. Secondly, pPVC foils containing three different NCs have been prepared and tested for mechanical, thermal and flame, and anti-migration properties using both standard and internal methods. Results have been compared to those of a neat pPVC foil and, due to the expected flame retardancy improvements, of a foil containing 2 phr of antimony trioxide (ATO). Even though certain properties appear to be slightly improved, the overall performance of these NCs are not completely satisfying.

none 8 no Pyrolysis of low-density polyethylene in an innovative batch pilot plant, with a hydraulic guard ensuring a safe process, was performed. The influence of process temperature on yield, distribution and composition of products was investigated. The oil/waxes were analyzed by gas chromatography coupled mass spectrometry, while pyrolysis gas was monitored online during the process by micro-gas chromatography. Pyrolysis were carried out at 450, 500, 550 and 600 °C. Results obtained show that low temperatures yield a greater amount of oil/waxes, and a gas enriched in carbon oxides and C3+ hydrocarbons. At higher temperatures, the gas fraction, riche in methane and hydrogen, is predominant over liquid products. This process has proved to be a versatile way to recover polyethylene wastes into valuable oils (rich in aliphatic and simple aromatic hydrocarbons) or gas, to be used as petrochemical feedstock or fuel, thus providing a sustainable method for material and energy recovery of waste packaging. mixed Zattini, Giorgio; Leonardi, Chiara; Mazzocchetti, Laura; Cavazzoni, Massimo; Montanari, Ivan; Tosi, Cristian; Benelli, Tiziana; Giorgini, Loris Zattini, Giorgio; Leonardi, Chiara; Mazzocchetti, Laura; Cavazzoni, Massimo; Montanari, Ivan; Tosi, Cristian; Benelli, Tiziana; Giorgini, Loris