Structured polymer dispersant for efficient phthalocyanine blue dispersion and color paste preparation

Abstract To overcome challenges in pigment dispersion, especially for difficult‐to‐disperse pigments like phthalocyanine blue, the structure of dispersants has been studied in recent years. Herein, we present the development and performance evaluation of a structured polymer dispersant for efficient dispersion of phthalocyanine blue and color paste preparation. The dispersant was synthesized using a two‐step free radical polymerization process, allowing precise control over its structure. The study investigates the impact of key factors on dispersion, including the molecular weight of the hydrophilic long‐chain poly(ethylene glycol) monomethyl ether (MPEG), the ratio of anchoring groups styrene (St) and dimethylaminoethyl methacrylate (DMAEMA), and the dispersant dosage. Optimal stability was achieved with MPEG‐400 as the hydrophilic long chain and a St:DMAEMA ratio of 1:1, along with a MPEG‐400AA:AA ratio of 0.5:1 at 2000 r min −1 . At a dispersant dosage of 25%, the particle size of the color paste measured 340 nm, with viscosity reaching 600 mPa·s. The structured dispersant effectively synergized spatial potential resistance and electrostatic effects to achieve stable pigment dispersion. These findings offer promising prospects for advancing dispersant technologies, with implications for improving color‐based applications across various industries, such as paints, coatings, and inks.