The flame retardant effect of magnesium hydroxide flame retardant is the speed at which physical or chemical changes can be prevented or inhibited during the combustion of the polymer material. The flame retardant effect of magnesium hydroxide blocker will be described in detail below.
1. The endothermic effect is difficult to raise the temperature of the polymer material. For example, borax has 10 molecules of water of crystallization. Since the crystal water is released, 141.8 kJ/mol of heat is taken, and the material is absorbed by heat. The temperature rise is suppressed, resulting in a flame retardant effect. The flame retardant effect of hydrated alumina is also due to its endothermic effect due to heat dehydration. In addition, some of the droplets often produced during the cracking of thermoplastic polymers can also exert a certain flame retardant effect by removing the heat of reaction away from the combustion zone.
2. The covering effect is to form a stable covering layer at a higher temperature, or to decompose to form a foamy substance, covering the surface of the polymer material, so that the heat generated by the combustion is difficult to be transmitted into the interior of the material, so that the polymer material The flammable gas generated by thermal decomposition is difficult to escape, and the material is insulated from the air, thereby inhibiting material cracking and achieving a flame retardant effect. Phosphate compounds and fire-retardant foaming coatings can function according to this mechanism.
3. Dilution effect These substances can generate a large amount of non-combustible gas when decomposed by heat, so that the flammable gas generated by the polymer material and the oxygen in the air are diluted to reach a flammable concentration range, thereby preventing the high polymer. The material is burning and burning. As the diluent gas, there are CO2, NH3, HCl, H2O, and the like. Such non-combustible gas can be produced by heating with amine phosphate, amine chloride, amine carbonate or the like.