2021-12-05 Pageview:732
Closed acid catalysts for solvent-based and water-based coating systems. This additive promotes the cross-linking of amino resin and hydroxyl-containing resin, especially HMMM-type low-reactivity melamine resin requires an accelerator to lower the curing temperature or reduce the baking time. Compared with pure parasulfonic acid, this adjuvant shows a very low viscosity increase during storage, which can extend the storage period by 1.5-3 times.
BYK Catalyst450 can have a baking temperature lower than 10-20°C (15-35°F) compared with other closed parasulfonic acids (such as morpholine or aminomethyl).
Phosphorus-nitrogen synergistic system flame retardant, phosphide and nitrogen-containing compounds, such as guanidine, guanidine, dicyandiamide, etc., are used together, have a significant synergistic effect, and constitute an intumescent flame retardant system for fire retardant coatings. The expansion reaction mechanism of the expansion system includes the decomposition of phosphate into phosphoric acid, the esterification of polyols, and the decomposition of polyol phosphate esters and regeneration of phosphoric acid. Generally, the positive combustion agents for intumescent flame retardant systems include: carbon-forming catalytic flame retardants that provide acid sources, generally free acid or substances that can release acid at 100 ~ 250 ℃ when heated, such as phosphoric acid, phosphate and ammonium polyphosphate, etc. ; Carbon-forming positive burning agents, mainly polyhydroxy compounds, such as pentaerythritol, glycerol, dextrin and starch, etc.; nitrogen-containing blowing flame retardants, such as urea, melamine and dicyandiamide.
Flame Retardant Mechanism
Flame Retardant Mechanism of Flame Retardant in Intumescent Fire Protection System
The fire prevention effect of the intumescent fire retardant system is mainly controlled by the following factors. Insulation effect: Use the coke layer to block heat conduction.
It can absorb a lot of heat during expansion: the expansion fire protection system softens, melts, evaporates, expands and the decomposition of the carbon source absorbs a lot of heat at high temperatures.
Blocking oxygen: the coking layer forms a covering effect.
The concentration of oxygen in the diluted air: non-combustible gas is released.
According to the research and practice of related materials and fire-retardant coatings, the flame retardant of the intumescent fire-retardant system can expand and foam to form a honeycomb carbonized layer when exposed to fire. Therefore, flame retardants usually require the following three basic ingredients: acid source one is generally free acid or a salt substance that can release inorganic acid at a certain temperature when heated, it is a catalyst or flame retardant for the formation of a carbon-forming foam layer. Such as phosphoric acid, phosphate and ammonium polyphosphate, etc.; foaming agent-generally nitrogen-containing compounds, such as urea, melamine and dicyandiamide, etc., these substances decompose at a certain temperature and produce Ne, NHs, NO, etc. The gas acts as a foaming agent; the carbon source is generally a carbon-rich compound of hydroxyl, which loses water and carbonizes under the catalysis of an acid to provide a carbon skeleton for the polytetrafluoroethylene wax melts foamed layer and make the foamed layer form a loose structure, such as Pentaerythritol, glycerol, dextrin and starch, etc., are indispensable to form the acid source, carbon source and foaming agent of the expansion fire protection system. They play a role in the expansion and foaming and fire resistance and heat insulation process. Synergy” effect.
Leave a message
We’ll get back to you soon