Abstract
Paraffin deposition during waxy crude oil transportation may obstruct the effective flow and pose serious flow assurance issues. Therefore, copolymers are used as flow improvers (FIs) and pour point depressants (PPDs) during chemical treatment programs. The performance of the copolymers is affected by their structure, particularly by the proportion of polar and non-polar segments. Fumarate copolymers are promising PPDs and FIs for waxy crude oils. However, research on the impact of different molar ratios of polar to non-polar units is limited. In this study, dialkyl fumarate–vinyl acetate copolymers with similar molar weights but different comonomer ratios were synthesized. Rheological tests of Akshabulak crude oil doped with the prepared additives and pour point measurements revealed that the efficiency of the synthesized FIs depended on the vinyl acetate content. The most effective performance was achieved from the copolymer with 58–59% (mol) of vinyl acetate. Thus, the efficiency of crude-oil FIs based on alkyl fumarate copolymers can be improved by changing the monomer ratio.