Synthesis and properties of block polycarboxylate dispersant containing benzene ring side groups by catalytic chain transfer polymerization (CCTP)

Abstract

In order to design and synthesize dispersants with controllable structure and narrow molecular weight distribution; to overcome the environmental pollution caused by the use of sulfur-containing reagents in RAFT polymerization method. A novel block polycarboxylic acid polymer was prepared by catalytic chain transfer polymerization using methacrylic acid and poly(ethylene glycol) monomethyl ether methacrylate as the hydrophilic monomers, and benzyl methacrylate as the hydrophobic monomer, and used as a coal water slurry dispersant. Structural and molecular weight testing of polymer using ¹H NMR, FTIR, and GPC. The results showed that the target products were successfully synthesized and the molecular weights of the polymers were all around 5000 g/mol. Discuss the rheological properties and stability of coal water slurry prepared with different monomer ratios of dispersants to find the optimal monomer ratio. It was proved that the dispersant with a monomer ratio of 4:1:0.8 had the best dispersing performance. In addition, the adsorption behavior of the dispersant was studied by TOC and XPS to elucidate the dispersion mechanism of the dispersant. It is proved that the dispersant on the surface of coal conforms to the monomolecular layer adsorption model, and the addition of the dispersant effectively reduces the content of hydrophobic groups on the coal surface and increases the content of oxygen-containing functional groups, thus improving the wettability of the coal surface.