Preparation of multi band photothermal responsive bio-based superhydrophobic self-healing poly(siloxane-urethane) coating

In order to improve the poor hydrophobicity and single repair conditions of traditional self-healing polyurethane coatings, prepolymers were synthesized with bio-based polyol castor oil (CO), self-made alkyl aryl modified silicone polyols (Si-OH) and isophorone diisocyanate (IPDI), and 4,4'-dithiodianiline (ODD) was used as chain extender containing dynamic disulfide bond, 4-methylumbelliferone (4-MU), as a bio-based end capping agent with reversible ring structure, was polymerized step by step to prepare a photothermal responsive bio-based superhydrophobic self-healing poly(siloxane-urethane) coating (PUSi). In this paper, the effect of the amount of alkyl aryl modified silicone polyol (Si-OH) on the properties of PUSi was studied. The results showed that PUSi with different alkyl aryl modified silicone polyol additions could achieve self-healing under heating, UV irradiation and infrared light irradiation, and the maximum repair efficiency could reach 91% through optical microscope (OM), 3D profilometer and universal testing machine; The contact angle meter proved that the introduction of alkyl aryl modified silicone polyol greatly improved the hydrophobicity of PUSi, and the maximum water contact angle was 162°. The coating has broad application prospects in the fields of self-cleaning fabrics, super hydrophobic surfaces, special protective clothing and so on.