Synthesis, characterization, and performance of alkyl methacrylates and tert-butylaminoethyl methacrylate tetra polymers as pour point depressants for diesel Influence of polymer composition and molecular weight

Abstract

This paper presents the synthesis, characterization, and performance analysis of methacrylate-based polymer additives containing tert-butylaminoethyl methacrylate in their structure on the low-temperature properties of diesel fuel. The additives were synthesized by free radical polymerization and the composition was varied between different comonomers. The molecular weight of the additives was reduced using a chain transfer agent and determined by gel permeation chromatography (GPC). The crystallization behavior of the additives and formulated diesel was observed by differential scanning calorimetry (DSC) and optical microscopy with polarization. Standard tests according to EN 116 for the Cold Filter Plugging Point (CFPP), ASTM D5771 for the Cloud Point and ASTM D5950 for the Pour Point (PP) have shown a great improvement in low-temperature properties. The synthesized additive containing 35 mol% methyl methacrylate and a 3:1 M ratio of dodecyl and octadecyl methacrylate showed the best results, lowering the CFPP of diesel by up to 10 °C (-18 °C) and the PP value by up to 30 °C (-48 °C) compared to pure diesel. Microscopic images confirmed that the additive changed the morphology of the wax crystals from needle-like to spherical and that the composition affects the crystal morphology.