文摘
A novel antioxidant epoxidized cardanol (ECD), derived from cardanol, was synthesized and characterized by FT-IR, 1H NMR, and 13C NMR. Oxidative stability of ECD used in vegetable oils and biodiesel was evaluated by pressurized differential scanning calorimetry (PDSC) and the Rancimat method, respectively. The results indicated that ECD exhibited antioxidative activity in soybean oil and increased its onset temperature (OT) by nearly 10 °C with 0.7 wt % ECD. It was also observed that other vegetables oils showed significantly improved oxidative stability with the addition of 0.7 wt % ECD. Olive oil showed the highest increased OT by 19.5 °C. Furthermore, ECD has superior antioxidant activity compared to synthetic antioxidant butylated hydroxytoluene (BHT) and thus could be used as an optimized primary antioxidant for biodiesel. Thermogravimetric analysis (TGA) indicated that ECD shows better thermal stability than cardanol. The data presented in this study indicate that ECD could be a new biobased antioxidant with better thermal stability.