Encapsulation of organic pigment via a facile dispersion approach and soap-free miniemulsion polymerization

Organic pigments are a commonly used colorant with various applications and promising prospects. However, the implement of organic pigments is hindered by poor dispersion stability and unsatisfactory weather resistance. Herein, encapsulated pigments are obtained via a facile dispersion approach and subsequent soap-free miniemulsion polymerization. The reactive emulsifier acting as dispersant and emulsifier in the polymerization integrates advantages of covalent bonding and steric hindrance effect, reducing the residue of excess reagents and improving the stability of pigment dispersion. Due to the interaction between polymers and the dispersants on the pigment surface, as well as the shielding effect of polymer in the core-shell structure, the soap-free nano-pigment composite particles exhibit better dispersion stability, enhanced weather resistance, superior rubbing fastness performance and anti-ultraviolet intrusion ability. In addition, the as-prepared nanocomposite could be applied to flat screen printing, inkjet printing, handwriting and other applications, significantly expanding the practical application value of pigments.