Preparation of structural colors on cotton fabrics with hydrophobicity and high color fastness through chemical bonds between polyphenolic hydroxyl groups and polysiloxanes

Textile structural color is an important method to replace the highly polluting coloring of traditional dyes and colors. The polydopamine (PDA) film with melanin-like characteristics can achieve multiple bright structural colors on the white cotton fabrics surface. However, PDA can cause cracking and inferior color fastness due to the influence of capillary tension during the film formation on the surface of cotton fabrics. A novel polysiloxane binder containing reactive groups, PVS, can form strong chemical bonds with PDA polymers, thereby improving the color fastness of structurally colored cotton fabrics. Moreover, the introduction of chemical bonds also reduced the proportion of surface hydrophilic groups, thus improved the hydrophobicity of the structural color film. Scanning electron microscopy was used to reveal the structure and morphology of the double-layer composite aggregates formed by the DA self-polymerization. Fourier transform infrared spectroscopy and X-ray diffraction spectroscopy were used to investigate the surface composition of structural color cotton fabrics. The color properties of PDA structured color films were revealed by UV-Vis diffuse reflectance and reflectance spectrometer.