Gel catalyst, mainly used as a room temperature silicone rubber curing catalyst, especially for deacetate type silicone products; it is characterized by faster catalytic speed than dibutyltin diacetate, and can be used in polyurethane elastomers, sprayed rigid polyurethane foam, hard foam high resilience molding foam, etc.
The chemical composition (mass fraction) of aluminum hydroxide for flame retardant is as follows:
AI(OH): 99.5%, pure Al(OH); the content of H2O should be 34.6%, the glowing weight loss of industrial products is generally 34%, Al zOs≥64%, Naz 0≤0.2%, Si Oz≤0.2 %, Fez O; ≤0.035%, Cu≤0.001%, Mn≤0.001%,
Aluminum hydroxide decomposes into Al2O when heated; and water, the reaction formula is as follows: heating
2AlKOH), plus A 1.0, +3H.O
The heat absorption at 240~500℃ is 1967.2kJ/kg, and the absorption of such a large heat is the main function of aluminum hydroxide as a flame retardant. The principle is that when the fire retardant coating meets fire, AI(OH): an endothermic reaction occurs according to the above formula. At 200°C, 2 Al(OH)a molecules can release 3 crystal waters, and the heat absorption is quite high. The temperature of the system is reduced, and montan wax composition the water generated by the reaction becomes steam at the combustion temperature.
It not only acts as a diluent, reduces the concentration of flammable gases, but also acts as a covering layer to isolate the air, that is, to isolate oxygen and block the flame. Play a role in preventing combustion, thereby reducing flammable conditions and preventing fire and flame spread. In addition, the reaction product AlzO; together with other carbides formed by combustion, forms an inert barrier around the material, preventing further decomposition of combustible materials, and at the same time reducing the diffusion rate of the thermally decomposed gas from the solid to the combustion zone. It can be seen that the flame retardant effect of AI(OH)s is obvious at 120r and the process is non-toxic and smoke-free. 80 aluminum hydroxide is heated to dehydration and 60 phase transition is very complicated. It can be analyzed by 40 thermal analysis. There are three endothermic peaks on the curve of thermal analysis 20, which indicates that the loss of crystal water is carried out in three stages of TIC.
Leave a message
We’ll get back to you soon