Self-repairing organic fluorine-silicon modified polyurethane waterproof coating and preparation method thereof

Abstract

The invention discloses a self-repairing organic fluorine-silicon modified polyurethane waterproof coating and a preparation method thereof. The coating comprises the following raw materials by mass:60-80 parts of polytetramethylene ether glycol, 15-30 parts of perfluoropolyether glycol, 40-60 parts of isophorone diisocyanate, 20-35 parts of 4, 4'-dithiodianiline, 20-30 parts of fluorine-containing hydroxyl silicone oil, 30-40 parts of tetrahydrofuran, 0.8-2 parts of dibutyltin dilaurate, 2-3 parts of Tween 80, 15-20 parts of nano calcium carbonate, 5-10 parts of nano calcium hydroxyphosphateand 10-20 parts of deionized water; the preparation method comprises the following steps of: S1, preparing a polyurethane prepolymer; S2, dissolving 4, 4'-dithiodianiline and fluorine-containing hydroxyl silicone oil in tetrahydrofuran, then adding the polyurethane prepolymer, and carrying out stirring reaction for 3-6h at a temperature of 60DEG C in a nitrogen atmosphere; and S3, preparing the organic fluorine-silicon modified polyurethane waterproof coating. According to the preparation method, a disulfide bond, a shape memory effect and organic fluorine-silicon modification are combined, and S-S, C-F and Si-O bonds are introduced into a polyurethane molecular chain, so that the hydrophobic and oleophobic properties, high and low temperature resistance, weather resistance, corrosion resistance and the like of the coating are remarkably improved.

Description

technical field [0001] The invention belongs to the technical field of waterproof materials, and in particular relates to a self-repairing organic fluorine silicon modified polyurethane waterproof coating and a preparation method thereof. Background technique [0002] Self-healing polyurethane material is a biomimetic intelligent material with high elasticity and self-healing ability. It mainly achieves the purpose of self-healing by introducing reversible covalent bonds, such as reversible disulfide bonds, reversible acylhydrazone bonds and Diels-Alder reactions. , Under the stimulation of external conditions such as light and heat, the cracks produced by polyurethane are repaired through the recombination of covalent bonds to avoid crack expansion. [0003] Organofluorosilicon material is a new type of material produced by molecular structure design and organic synthesis of organic fluorine and organic silicon materials. It has the advantages of both organic fluorine and o...

AI Technical Summary

Problems solved by technology

[0004] In the prior art, although various synthesis methods of self-healing polyurethane materials or methods for modifying polyurethane with organofluorosilicon have been disclosed, there is no further modification of disulfide bond-containing polyurethane with organofluorosilicon to make it both repeatable self-healing and Disclosure of related documents or patents on the function of shape memory effect, such as the patent application number CN201910799259.X, which discloses a double self-healing polyurethane coating containing disulfide bonds and hydrogen bonds for invisible car coverings and its preparation method. One or both of polybutadiene and hydroxyl-terminated polysiloxane are copolymerized with diisocyanate and disulfide bond-containing chain extender A to form self-healing polyurethane, but no further modification with organofluorosilicon

Images