Synthesis And Application Of Mannich Dispersant For Pigment

Pigment dispersing is important production process of the coating,ink,plastic and cosmetic and so on.To obtain excellent ink dispersing system,it is difficult to rely on the reciprocity of resin,pigment and solvent.Dispersant is indispensable.A new type of pigment dispersant has been investigated in this paper.The dispersant has been synthesized using organic pigment intermediate(salicylic acid,2-hydroxy-3-naphthoic acid and dimethyl succinylosuccinate),formaldehyde and long-chain amine(Octadecyl amine,polyether amine) as starting materials via Mannich reaction.The synthesized production are characterized by Infrared Spectroscopy(FT-IR),Magnetic Resonance Spectroscopy(~1H-NMR),Thin-Layer Chromatography and Chromatographic Column.Because the major reaction of the dispersant is Mannich reaction,we define the dispersant as the Mannich dispersant for pigment.Tint strength and fineness are the important index of the pigment dispersing performance.On equal terms,The hig tint strength and the low fineness indicate that the pigment granule is thin and the dispersing performance is excellent.The mannich dispersants are processing some application tests.The dispersant with the reaction of octadecyl amine and salicylic acid or 2-hydroxy-3-naphthoic are applied in offset ink via pigment Red 57:1 and pigment Yellow 13.Through optimizing the doze of dispersant,the tint strength can be improved 10%-16%and the fineness can be declined 6-7μm.The dispersing effect of the dispersant synthesis of the 2-hydroxy-3-naphthoic excel the synthesis of the salicylic acid.The dispersant with the reaction of polyether amine and salicylic acid or 2-hydroxy-3-naphthoic are applied in solvent ink prepared by the Pigment Yellow 83 and in water ink prepared by the Pigment Red 57:1.Polyether amine can vary in different molecular weight and HLB value which can suitable to solvent and water ink.The tint strength of the pigment can be improved.We also discover that the dispersing effect of the dispersants synthesis of the 2-hydroxy-3-naphthoic excel the synthesis of the salicylic acid. The dispersants prepared by the polyether amine and dimethyl succinylosuccinate are applied in solvent and water ink via pigment Red 122.The dispering performance is closely related to the molecular weight and HLB value of the polyether amine.And the dispersing performance of the dispersants which are oxidated by the hydrogen peroxide excel the dispersant which are not oxidated by the by hydrogen peroxide.The innovation of the research is according to designing principle of molecular structure of polymer.The anchoring group are some organic pigment intermediates which are similar to pigment structure and make the dispersant absorb the surface of grain firmly.The long-chain amine as a solvatable chain can vary in different molecular weight and HLB value which can suitable to different ink system.They extend the application area of the production and improve the application performance of product.They extend the application area of the production and improve the application performance of product.