Synthesis of polyacrylate dispersant by DPE method and its application in inkjet ink of titanium dioxide

In this article, we synthesized a series of poly butyl acrylate-co-methacrylic acid-2-acrylamido-2-methyl propanesulfonic acid (PBAS) with different molecular weight and monomer molar ratios by 1,1-diphenylethene (DPE) method on industrial scale. The PBAS was applied as a dispersant for waterborne TiO2 paste to prepare waterborne inkjet ink. The successful synthesis of PBAS was confirmed by FTIR and 1H-NMR. To evaluate the printability and storage properties of pastes and inks, we characterized the particles, particle distribution, the storage modulus, viscosity, precipitation coefficient, and delamination height. The method creatively used in our study to characterize the printing smoothness of the ink in the industrial practical application was the filter rate of ink. We also proposed a method of using soft and hard precipitation to characterize the precipitation situation. The results of the experiment indicated that compared with commercial dispersants, PBAS5/6 had excellent performance in printing flow and anti-settling performance. This paper demonstrates the optimum dispersibility of PBAS was obtained when the molecular weight was 8500, the acid value was 100 mg KOH/g, and the 2-acrylamido-2-methylpropanesulfonic acid (AMPS) content was 20%. This fruitful work pointed out the great prospects of industrial synthetic water-based dispersants.