When making pvc tarpaulin, a large number of additives will be added. One of the more common flame retardants can be used to make polymeric flame retardants. So what is the mechanism of action of this flame retardant?
1. Inflammable gas suffocation: The flame retardant decomposes incombustible gas when heated, and the concentration of combustible gas decomposed by combustibles is lower than the lower limit of combustion. At the same time, it can dilute the oxygen concentration in the combustion area, prevent combustion, and achieve flame retardant effect.
2. Inhibition of chain reaction: According to the chain reaction theory of combustion, it is the free radical required to maintain combustion. Flame retardants act in the gas phase combustion zone to capture free radicals in the combustion reaction, thereby preventing flame propagation, reducing the flame density in the combustion zone, and reducing the rate of combustion reaction until termination.
For example, the evaporation temperature of halogen-containing flame retardants is the same or similar to the decomposition temperature of polymerization. When the polymerization is thermally decomposed, the flame retardant of pvc tarpaulin also volatilizes at the same time. At this time, the halogen-containing flame retardant and the thermal decomposition product are in the gas phase combustion zone at the same time, and the halogen can capture the free radicals in the combustion reaction and interfere with the combustion chain reaction.
At present, when using pvc tarpaulin, the first consideration for pvc tarpaulin manufacturers is how to understand its physical properties. After all, its physical properties are more important properties, and only a detailed understanding can ensure that workers can use it skillfully. Therefore, when it appears, we should at least know how to calculate its density, calculate it in various ways, find the difference from it, and even analyze the source of the error.