Green nanocomposites from rosin-limonene (Ros-Lim) copolymers based on Algerian organophilic-clay named Maghnite-CTA+ (Mag-CTA+) were prepared by in-situ polymerization using different amounts (1, 5 and 10% by weight) of Mag-CTA+ and azobisisobutyronitrile as a catalyst. The Mag-CTA+ is an organophilic montmorillonite silicate clay prepared through a direct exchange process; the clay was modified by ultrasonic-assisted method using cetyltrimethylammonuim bromide in which it used as green nano-filler.The preparation method of nanocomposites was studied in order to determine and improve structural, morphological, mechanical and thermal properties ofsin.The structure and morphology of the obtained nanocomposites(Ros-Lim/Mag-CTA+) were determined using Fourier transform infrared spectroscopy, X-ray diffraction, scanning electronic microscopy and transmission electronic microscopy. The analyses confirmed the chemical modification of clay layers and the intercalation of rosin-limonene copolymer within the organophilic-clay sheets. An exfoliated structure was obtained for the lower amount of clay (1% wt of Mag-CTA+), while intercalated structures were detected for high amounts of clay (5 and 10% wt of Mag-CTA+). The thermal properties of the nanocomposites were studied by thermogravimetric analysis (TGA) and show a significant improvement inthe thermal stability of the obtained nanocomposites compared to the purerosin-limonene copolymer (a degradation temperature up to 280 °C).
A new method to synthesise polyethylene glycol dimethacrylate (PEGDM) with various molecular weights (1000, 3000, 6000 and 8000 g/mol) of polyethylene glycol (PEG) has been developed. This technique consists in using Maghnite-H+ as eco-catalyst to replace еriethylamine, which is toxic. Maghnite-H+ is a proton exchanged montmorillonite clay which is prepared through a simple exchange process. Synthesis experiments are performed in solution using dichloromethane as solvent in the presence of methacrylic anhydride. The effect of reaction time, temperature, amount of catalyst and amount of methacrylic anhydride is studied in order to find the optimal reaction conditions. The synthesis in solution leads to the best yield (98 %) at room temperature for the reaction time of 5 h. The structure of the obtained macromonomers (PEGDM) is confirmed by FTIR, 1H NMR and 13C NMR, where the methacrylate end groups are clearly visible. Thermogravimetric analysis (TGA) is used to study the thermal stability of these obtained macromonomers. The presence of unsaturated end group was confirmed by UV-Visible analysis.
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