The types of additives commonly used in polyurethane waterproof coatings currently include catalysts, chain extenders, coagulants, ultraviolet absorbers, anti-aging agents, solvents and defoamers.
The catalysts are mainly organic metal salts and organic amines, such as dibutyltin dilaurate, stannous octoate, stannous oleate, etc., according to the reaction temperature and time, the compound catalyst is used, the dosage is 0.03% About 0.06%.
The coagulant can be benzoyl chloride, citric acid, hydrochloric acid, phosphoric acid, etc., mainly to maintain the acidity of the medium, you can choose 85% phosphoric acid, the dosage is generally 0.2%-0.4% of the amount of polyether.
UV absorbers mainly include benzophenone compounds, heterocyclic compounds and metal complexes, anti-aging agents mainly include phenols, amines, etc. The combined use of UV absorbers and anti-aging agents is better. The solvent is generally xylene and butyl acetate, and the dosage is not more than 10%.