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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]

This work is aimed to study the suitability of cardanol and its derivatives as plasticizers for poly(lactic acid), PLA. Differential scanning calorimetry (DSC) was used to assess the plasticizing effectiveness of cardanol (CARD) and its derivatives, cardanol acetate and epoxidated cardanol acetate, comparing the results with those obtained with a commercially available plasticizer, poly (ethylene glycol), PEG, with an average molecular weight of 400 g mol−1. Measurement of the glass transition temperature highlighted that, among the tested cardanol derivatives, neat cardanol is the most effective plasticizer for PLA. In fact, the glass transition temperature of PLA plasticized by CARD is only slightly higher than that of PLA plasticized by PEG. This is attributed to the lower compatibility between PLA and CARD compared to PLA and PEG, as estimated by the interaction radius. Therefore, cardanol could represent a technically valid, economic, and largely available plasticizer for PLA. Moreover, DSC, an X-ray diffraction analysis, showed that, compared to PEG, the addition of CARD involves a limited increase of the rate of crystallization, even in this case, due to its lower compatibility with PLA. Dynamic mechanical analysis showed that, below glass transition, PEG is able to reduce the stiffness of PLA by a higher extent. However, as the temperature increases, retention of the shear modulus of PEG-plasticized PLA is much higher than that of CARD-plasticized PLA. As a consequence, above glass transition, the stiffness of CARD-plasticized PLA becomes lower than that of PEG-plasticized PLA. Therefore, despite its lower compatibility with PLA, CARD can impart to plasticized PLA lower modulus compared to PEG, when the plasticizer content is high enough to reduce the glass transition below room temperature. [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]

This work is aimed to the development and property optimization of cardanol derived plasticizers. To this purpose, different plasticizers were produced though different epoxidation routes, characterized by low toxicological and environmental impact. The plasticizers are characterized by different yield of epoxidation of the alkyl chain double bonds. The properties of the cardanol derived plasticizers were compared to the properties of commercial plasticizers, either phthalates or natural derived. Mechanical properties of soft PVC plasticized by cardanol derivatives were shown to be comparable to those of PVC with commercial plasticizers. The plasticizing efficiency of cardanol derivatives was significantly improved by increasing the yield of epoxidation. Also, mechanical properties performed after ageing showed the excellent stability of the properties of the cardanol derived plasticizer characterized by the higher yield. Evaluation of the property retention index after ageing indicated that such plasticizers showed an improved stability of properties compared to other commercial plasticizer. The results obtained highlight the relevance of an high conversion of the double bonds into epoxies in order to produce high quality plasticizers. [ABSTRACT FROM AUTHOR]

This work was aimed to test the suitability of an epoxidized cardanol derived plasticizer for the production of soft PVC characterized by low environmental and toxicological impact soft PVC. Nowadays, the use of natural derived plasticizer in soft PVC industry is emerging as valid alternative towards conventional phthalate plasticizers, in order to reduce the environmental and toxicological impact of soft PVC. In facts, cardanol is a natural and renewable resource, characterized by a wide worldwide availability. In addition, being derived from cashew nut shell liquid, which is a by-product of cashew nut shell industry, it does not contribute to the subtraction of resources from the food chain, in contrast, for example, to epoxidized soybean oil. To this purpose, soft PVC samples were produced in an industrial plant, using both cardanol derived and phthalate plasticizer. Thermal and mechanical characterization showed that the properties of PVC plasticized by cardanol derivative are comparable to those of soft PVC obtained by phthalate, which is a clear indication of the good plasticizing effectiveness of cardanol derivative, and highlights its potential for the production of soft PVC characterized by reduced environmental and toxicological impact. [ABSTRACT FROM AUTHOR]