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Beer bagasse is a residue waste produced in great amounts; nevertheless, it is still underestimated in the industry. The aim of this paper is to develop an innovative and efficient methodology to recycle the beer bagasse by producing Poly-lactic acid(PLA)-based bio-composites, in the forms of pellets and filaments, to be used in additive manufacturing processes. To assess the suitability of beer bagasse for extrusion-based 3D printing techniques, it was, firstly, physically and chemically characterized. Then, it was added in combination with different kinds of plasticizers to PLA to make bio-composites, analyzing their thermal and physical properties. The results prove the great potential of bagasse, evidencing its printability. Both composites' pellets and filaments were used in two different 3D printing machines and the mechanical properties of the 3D-printed models were evaluated as a function of the composition and the kind of technology used. All the used plasticizers improved processability and the polymer–bagasse interface. Compared to neat PLA, no changes in thermal properties were detected, but a lowering of the mechanical properties of the 3D-printed composites compared to the neat polymers was observed. Finally, a comparison between the efficiency of the two 3D printing techniques to be used with the bio-based composites was performed. [ABSTRACT FROM AUTHOR]

This paper is aimed at studying the thermal properties of poly(lactic acid), PLA with different plasticizers. Plasticized PLA was obtained by mixing and extruding PLA with 20 mass% of neat cardanol, epoxidized cardanol acetate (ECA) and poly(ethylene glycol) (PEG) 400. The glass transition of completely amorphous samples, melting and crystallization behavior of plasticized PLA were analyzed by differential scanning calorimetry. Results obtained show that, below Tg, a higher enthalpy relaxation occurs for PLA plasticized by cardanol derivatives. This is indicative of a faster mobility of PLA chains below Tg, when cardanol derivatives are used as plasticizers. On the other hand, an opposite behavior was observed for the crystallization studies. In facts, a much faster crystallization was found for PLA plasticized by PEG, which in turn indicates a much higher mobility of PLA chains above Tg compared to PLA plasticized by cardanol derivatives. Mechanical properties obtained on completely amorphous samples show that PLA plasticized by ECA is characterized by lower modulus, which is indicative of a more efficient plasticization. On the other hand, the thicker crystals formed during crystallization of PLA plasticized by ECA involve a more relevant increase in the modulus in semicrystalline samples. [ABSTRACT FROM AUTHOR]

This work is aimed to study the application of a bio-based plasticizer, obtained by acetylation and epoxydation of cardanol, for the production of soft PVC foams. The use of epoxidized cardanol acetate allowed obtaining a more efficient foaming of soft PVC compared to phthalate plasticizer bis(2-ethylhexyl) phthalate (DEHP), mainly due to the lower viscosity attained in the decomposition range of azodicarbonamide (AZDC). As a consequence, the foams produced by epoxidized cardanol acetate showed a lower density compared to those produced with DEHP. The lower density yielded lower values of compressive modulus. However, the modulus was shown to be not only dependent on the density, but also showed a direct dependence on the type of plasticizer used, in addition to processing temperature and AZDC content. As a consequence, the specific compressive modulus also showed a direct dependence on the type of plasticizer, processing temperature and AZDC content. Such dependence was explained by considering different cellular morphologies developed during foaming under different processing conditions, including type of plasticizer. In particular, it was shown that the lower viscosity attained by epoxidized cardanol acetate plasticized PVC involved an increase of the average pore size of the foam, which was shown to be the main cause of the variation of the specific compressive modulus. [ABSTRACT FROM AUTHOR]

Abstract This work is aimed to study the effect of cardanol derived plasticizers on the tensile modulus of poly(lactic acid), PLA. Neat cardanol, cardanol acetate (CA), and epoxidized cardanol acetate (ECA) were used, at contents ranging between 10% and 30%. For comparison purposes, another green plasticizer, poly(ethylene glycole) (PEG), was used. Tensile tests were carried out to evaluate the influence of the type and the amount of plasticizer on the tensile modulus of injection molded PLA. Within the examined composition limits, PLA plasticized by cardanol derivatives showed lower modulus than PEG plasticized PLA. The tensile modulus of plasticized PLA was correlated to the evolution of glass transition temperature and degree of crystallinity. At low plasticizers content, the modulus of PLA decreased as the glass transition temperature decreased, due to a better miscibility of the plasticizer with PLA. The opposite occurred at high plasticizer content; in this case, the higher modulus found for more compatible plasticizers were attributed to an increased crystallization kinetic. The evolution of elastic modulus as a function of glass transition temperature and degree of crystallinity was analyzed using a single equation capable to fit the data obtained using different plasticizers. Highlights • Cardanol derivatives were used for plasticization of poly(lactic acid). • Some cardanol derivatives had a plasticizing effectiveness higher than that of PEG. • This involved a decrease of the modulus and increase of ductility and toughness. • The higher plasticizing effectiveness is due to reduced crystallization kinetics. [ABSTRACT FROM AUTHOR]

This work is aimed to study the suitability of cardanol derivatives as plasticizers for poly(vinyl chloride), (PVC). The plasticizers are obtained by chemical modification of cardanol, a natural, renewable resource, obtained as a by‐product of the cashew nut shell industry. Due to the choice of environmentally friendly chemical modification routes, partial conversion of cardanol to the target compounds was obtained. Consequently, the tested plasticizers were composed of a mixture of different cardanol derivatives. Rheological tests on PVC plastisols obtained with neat cardanol showed that cardanol must be subjected to chemical modifications, such as acetylation and epoxidation, in order to perform as an effective plasticizer. In particular, only after epoxidation, does the cardanol derivative become fully soluble in PVC. PVC plastisols obtained with such cardanol derivatives present a similar gelation temperature compared to bis (2‐ethylhexyl) phthalate (DEHP) based plastisols. Mechanical properties of the flexible PVC produced by the addition of cardanol derived plasticizer after epoxidation are also comparable to those attained by the use of DEHP. Nevertheless ageing tests showed an accelerated migration of cardanol derived plasticizer, attributed to the loss of unreacted cardanol present in the plasticizer, which was in turn responsible for a significantly faster degradation of the properties, compared to flexible PVC containing DEHP. This highlights the relevance of achieving a high yield of the acetylation and epoxidation reactions, which is a relevant issue of the future research and development activities in this field. J. VINYL ADDIT. TECHNOL., 24:E62–E70, 2018. © 2016 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

This work is aimed to the study of the thermal and UV stability of Poly Vinyl Chloride (PVC) plasticized by cardanol derivatives. To this purpose, soft PVC obtained by cardanol derivatives, as well as by commercial plasticizers, were subjected to different sources of degradation, i.e. thermal treatments and UV weathering, and characterized by means of the tensile tests. Analysis of variance (ANOVA) was used to highlight the statistical significance of the type of plasticizer and treatment of soft PVC on the mechanic properties. In particular, estimation of the retention index of different plasticizers to different sources of degradation allowed highlighting the better performances of PLACARD compared to the other commercial plasticizers. In absence on any relevant loss of plasticizer during thermal treatment or UV weathering, the change in mechanical properties was attributed to change in the chemical structure of PVC homopolymer, which was studied by FTIR analysis. It was shown that the better retention of property of soft PVC plasticized by PLACARD is due to a lower amount of thermal or UV activated degradation. Therefore, the results highlight that PLACARD plasticizer can also act as an efficient thermal and UV stabilizer, which could increase soft PVC durability and recyclability, and contribute to a reduction of the amount of thermal and UV stabilizers, with additional relevant effects on the toxicological and environmental impact of soft PVC. [ABSTRACT FROM AUTHOR]

The aim of this work is the development and characterization of biodegradable thermoplastic recycled carbon ashes/maize starch (TPAS) composite films for agricultural applications. A proper plasticizer, that is, glycerol, was added to a commercial maize starch in an amount of 35 wt.%. Carbon-based ashes were produced by the biomass pyro-gasification plant CMD ECO 20, starting from lignocellulosic wastes. The ashes were added to glycerol and maize native starch at different amounts ranging from 7 wt.% to 21 wt.%. The composite was mixed at 130 °C for 10 min and then molded. The effect of the different amounts of carbon based ashes on the thermal and physical-mechanical properties of the composite was assessed by using several techniques, such as rheology, wide-angle X-ray diffraction (WAXD), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), moisture absorption, degradation and mechanical tests. The presence of the carbon waste ashes allows to improve thermal and durability performances of the thermoplastic starch (TPS) films. It reduces the water absorption of starch matrix and strongly decreases the deterioration of starch, independently from fillers amount, enhancing the lifetime of the TPS films in outdoor conditions. In addition, the waste carbon ashes/maize starch films present an advantage in comparison to those of neat starch; it can biodegrade, releasing the plant nutrients contained in the ashes into the soil. In conclusion, this approach for recycling carbon waste ashes increases the efficiency of industrial waste management, along with a reduction of its impact on the environment. [ABSTRACT FROM AUTHOR]