Flame Retardant Curtain Fabric Suppliers introduce the […]
Flame Retardant Curtain Fabric Suppliers introduce the functional principle of flame retardant:
(1) Endothermic mechanism
Some flame retardants have an endothermic function. When they are heated, they will absorb heat when they decompose (aluminum hydroxide, magnesium hydroxide, etc.), which can cool the flame retardant substrate to the temperature necessary to maintain combustion. below temperature. In addition, this type of flame retardant can also generate water vapor or other gases during the endothermic decomposition process, which isolates the substrate from the air and inhibits the further development of the combustion process.
(2) Shielding mechanism
The shielding mechanism is also called the isolation effect. This type of flame retardant is generally used in coatings and is one of the important components of coatings. When the wood is heated or burned, the flame retardant components in the coating will release fire extinguishing gas to prevent it from burning. The coating expands to form a uniform and dense foam insulation layer, which isolates oxygen, inhibits the transfer of heat from the heat source to the substrate, delays the time for the combustible substrate to reach the ignition temperature, and prevents the spread of the flame.
(3) Dilution mechanism
Flame retardants decompose at high combustion temperatures to produce a large amount of non-combustible gases, such as water, carbon dioxide, and ammonia. These incombustible gases dilute the concentration of combustible gases in the gas phase, thereby inhibiting or terminating combustion.
(4) Inhibition mechanism
High polymer is an important part of this kind of flame retardant. The combustion of high polymer is mainly a chain reaction generated by OH free radicals. Such substances have the ability to repeatedly react with OH free radicals to generate water, which can inhibit the generation of free radicals. chain reaction. For example, halogen-based flame retardants produce highly active free radical scavengers during combustion, which can capture flammable groups in the gas phase; phosphorus-containing flame retardants will generate metaphosphoric acid during combustion, forming an isolation barrier to prevent building materials from being damaged. Exposure to the atmosphere to achieve the effect of flame retardant.
The heat setting and baking temperature and time of the flame retardant must be compatible with the structure of the fabric fiber, but it is worth noting that the baking temperature of the flame retardant must be higher than the heat setting temperature of the fabric. It is the flame retardant that may remain on the surface of the fabric after finishing, so pay attention to cleaning!