Specific migration of IRGASTAB 17 MOK and DBP from rigid and plasticized poly(vinyl chloride) into organic liquids

The aim of this paper is the determination of the specific migration of an plasticizer and an organotin heat stabilizer (IRGASTAB 17 MOK) from plasticized and rigid (PVC) into organic liquids hexane and ethanol simulating fatty food. The migration test conditions were 10 days at 40°C and 2 hours at 70°C. FTIR and UV-Visible at 490 nm spectroscopy and gas chromatography were used to investigate the migration phenomena. The influence of various parameters such as temperature, time of contact and the nature of food simulant were considered. The results show that plasticizer accelerates the heat stabilizer migration. On the other hand that gas chromatography could be substituted by FTIR spectroscopy to investigate the DBP migration phenomena. It is a simple, low cost and rapid method which can be used

Mechanical characterization of LDPE/PLA blends/wood flour composites

In this work, biocomposites based on low density polyethylene (LDPE), a current thermoplastic, and polylactic acid (PLA), a biodegradable thermoplastic, blends were prepared in presence of various amounts of wood flour (0 to 40 wt %). For that purpose, the following LDPE/PLA/wood flour composites were considered: 20/80/0, 2080/5, 20/80/10, 20/80/20, 20/80/30, 20/80/40). The evolution of elongation at break, strength at break and Young's modulus was followed as a function of the wood flour concentration. The results showed that the properties of the considered composites depend on the level of wood flour

Migration of new bio-based additives from rigid and plasticized PVC stabilized with epoxidized sunflower oil in soil

International audienceCommercial sunflower oil was epoxidized and the epoxidized sunflower oil (ESO) was used as a thermal stabilizer for poly(vinyl chloride) (PVC). Rigid and plasticized formulations stabilized with ESO as a new biodegradable stabilizer and epoxidized soya bean oil (ESBO) as a commercial stabiliser were compared. Two plasticizers were used: dioctyl phthalate (DOP) and diisononyl adipate (DINA). The artificial aging of the PVC samples was investigated under uncontrolled temperature in the laboratory for 4 months. The modifications of the structure of the polymer were followed by Fourier transform infrared spectroscopy (FTIR). The morphological changes were followed by scanning electron microscopy (SEM). Furthermore, the evolution of the bacterial growth, variation of pH and variation of mass were considered

Kinetics of tungsten-catalyzed sunflower oil epoxidation studied by 1H NMR

International audienceSunflower oil (SO) is a renewable resource that can be epoxidized, and the epoxidized SO has potential uses as an environmentally friendly and reactive material in polymeric formulations, especially for polyvinyl chloride. SO was epoxidized with peracetic acid, which was either preformed or prepared in situ. In order to optimize the formation of oxirane rings, the epoxidation and the extent of the side reactions were studied at different temperatures. The peracetic acid was obtained by acidic catalysis in the presence of a cation-exchange resin. The optimum conversions were obtained within a 4-h reaction period at 55 7C by the in situ epoxidation technique. The epoxidation was also carried out with hydrogen peroxide in the presence of peroxotungstic acid complexed with lipophilic phosphorus-based ligands. 1H NMR was used to define the new indices, which are the mean numbers of C=C double bonds and oxirane rings per fatty acid chain, respectively. This allowed monitoring of the reaction and quantification of the results. Peroxotungstic catalysts appeared less performing than peracids in the epoxidation of SO, but were found very efficient for the epoxidation of the SO methyl esters

Isothermal and dynamic thermogravimetric degradation of rigid and plasticized poly(vinyl chloride)/poly(vinyl methacrylate) blends

International audienceThe thermal degradation of rigid and plasticized poly(vinyl chloride) (PVC)/poly (methyl methacrylate) (PMMA) blends was investigated by means of isothermal and dynamic thermogravimetric analysis in a flowing atmosphere of air. For that purpose, blends of variable composition from 0 to 100 wt% were prepared in the presence (15, 30 and 50 wt%) and in the absence of di-(2-ethyl hexyl) phthalate (DEHP) as plasticizer. The thermal degradation of the blends was investigated by isothermal thermogravimetry at 180°C during 120 min. It was found that the main processes are the dehydrochlorination of PVC and depolymerization of PMMA. The dynamic thermogravimetric experiments were carried out in the temperature range of 30 - 550°C. The results showed that the thermal degradation of rigid and plasticized PVC/PMMA blends in this broad range of temperatures is a three-step process and that PMMA exerted a stabilizing effect on the thermal degradation of PVC during the first step by reducing the dehydrochlorinatio

Valorization of regenerated LDPE by blending with EPDM in the presence of peroxide

The present work aims to the valorization of regenerated low density polyethylene (LDPE) by blending with small quantities of ethylene-propylene-diene monomer (EPDM). Three types of regenerated LDPE (rLDPE) from different waste sources (greenhouses, milk pouches,...) were characterized in terms of physico-chemical (density, melt flow index, water absorption, melting temperature and structure by Fourier transform infrared (FTIR) spectroscopy) and mechanical properties (tensile properties and hardness). The optimization of the peroxide content required for the crosslinking of the LDPE/EPDM blends was due by measuring torque and tensile strength. Once the peroxide content was optimized, different blends were obtained by varying the EPDM content. Then they were characterized physically (density, water absorption) and mechanically (tensile properties and hardness). Finally, the blends behavior under the conjugated effect of heat and water was determined at 70 C for 7 days. The obtained results showed that this kind of blending has contributed in improving the performance of regenerated LDP

Investigation of the Biodegradability of LDPE/PLA Bioblends: Comparison of Hydrolysis and Soil Burial Tests

The present work concerns the preparation and characterization of new biodegradable materials by mixing poly lactic acid (PLA), a biodegradable polymer, with low density polyethylene (LDPE), a current thermoplastic that can be bio-based. For that purpose, LDPE/PLA blends of variable composition (100/0, 80/20, 50/50, 20/80, 0/100) were prepared. They were characterized in terms of physical properties (density, melt flow index), thermal properties (melting temperatures) and mechanical properties (tensile and Shore D hardness). Their morphology was investigated by scanning electron microscopy. Hydrolysis and soil burial tests were conducted to study the biodegradation behavior. The weight loss of the samples with time was followed. The structural changes were investigated by FTIR spectroscopy and microscopic observation. Mechanical analysis showed that the strength at break increased with the level of PLA while the elongation at break decreased strongly due to the non miscibility of the two polymers. The SEM micrograph of blends 20/80, and 80/20 evidenced poor adhesion at the interface between the two polymers. The PLA confers a brittle character to its blends. The highest rates of mass variation were observed for the blend containing 50 and 80 wt% of PLA and were about 72 and 55 wt% after 45 days for the hydrolysis test and 10 and 2.5 wt% after 18 weeks of soil burial