Methacrylate terpolymers with short-chain comonomers as pour point depressants for diesel fuel and blends with biodiesel

This paper describes the synthesis of methacrylate-based terpolymer additives for diesel and biodiesel fuel that improve its properties at low temperatures. The synthesized additives contained different amounts of short-chain (methyl and benzyl) and long-chain (dodecyl and octadecyl) methacrylate comonomers. The crystallization behaviour of the additives and the formulations with diesel and biodiesel was observed by differential scanning calorimetry (DSC) and optical microscopy with polarization. DSC showed that the additives had a different effect on the crystallization temperature of the formulations. Microscopic images showed that the presence of additives influenced the size and number of wax crystals at low temperatures. Standard ASTM D5950 tests for pour point (PP) showed a large improvement in formulations with additives. In formulations with diesel, the addition of additives improved the PP value of diesel from -18 degrees C to -45 degrees C and in B10 diesel/biodiesel formulations from -18 degrees C to -54 degrees C.