With the increasing awareness of environmental protection, water-based polyurethane catalyst coatings are receiving more and more attention. The catalyst is water-based An important component of polyurethane coatings.
Polyurethane coatings have excellent abrasion resistance, flexibility and chemical resistance, but solvent-based coatings contain large amounts of organic solvents, which can seriously pollute the environment. With the improvement of people’s quality of life, various environmental protection regulations have strict limits on the emission of volatile organic compounds (VOC) and the content of harmful solvents.
Because water-based polyurethane uses water as the dispersion medium, it not only has the advantages of being non-toxic, non-polluting to the environment, safe and reliable, but also has some important performance characteristics of solvent-based polyurethane ID. Therefore, more and more people are paying attention to and studying water-based polyurethane, and its applications are becoming more and more widespread. Although the amount of catalyst used in the water-based polyurethane system is not large, it plays an important role in shortening the pre-polymerization reaction time, film-forming time and improving film-forming quality in the pre-polymerization of water-based polyurethane and the film-forming and curing of water-based polyurethane. Therefore, the research on high-performance catalysts is an important part of the research on water-based polyurethane systems.
For example: amine catalystPolyurethane catalyst” style=”color: rgb(0, 112, 192); text-decoration: underline;”>Polyurethane catalyst Amines can be divided into 4 types: (1) Aliphatic amines: including triethylamine, diethylenetriamine, etc.; (2) Alicyclic amines, such as triethanolamine, ethanolamine, etc.; (3) Alcoholamines , such as triethanolamine, ethanolamine, etc.; (4) Aromatic amines. In the polyurethane industry, triethylenediamine, N-alkylmorpholine, etc. are the most commonly used catalysts. Good catalytic activity can be used in the film formation of one-component water-based polyurethane.
The catalytic activity of tertiary amine compounds on polyurethane reactions mainly depends on it. Yu: The surface value is the alkalinity of the tertiary amine. The greater the alkalinity, the higher the catalytic activity. When the amine molecule has an electron-repelling substituent, the electron cloud density on the nitrogen atom will increase, the alkalinity will increase, and the catalytic activity will increase. Enhancement, on the contrary, catalytic activity decreases.
