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Principle of halogen-free flame retardant


Release time:

Jun 15,2021

[Summary]What is the principle of halogen-free flame retardant? Today, I will give you a detailed introduction, please take a good look.

  halogen-free flame retardantWhat is the principle of flame retardant? Today, I'll give you a detailed introduction, please have a good look.

Halogen-free flame retardant, as the name suggests, is an additive that can prevent plastic from catching fire or inhibiting flame spread. Its function is to inhibit or prevent the physical or chemical change rate of polymer materials in the combustion process. Its principle is mainly manifested in the following aspects:

Condensed phase flame retardant principle: can promote the polymer in the combustion process of crosslinking into carbon (promote dehydration, condensation, cyclization, crosslinking and other reactions, and increase the carbonization residue) is a condensed phase flame retardant,

Such as: 1. Provide a layer of oxygen insulation coating, such as phosphate ester halogen-free flame retardant produced when burning is oxygen barrier coating.

2. Produces a gas that can suffocate the flame. For example, antimony trioxide encounters HCL produced by combustion in polyvinyl chloride and reacts to produce smoldering gas, namely antimony nitrogen oxide.

Gas phase flame retardant principle: The halogen-free flame retardant added can capture the free radicals in the gas phase during the combustion of the material, which generally belongs to the gas phase flame retardant principle.

Such as: produce free radicals, can react with plastic, play a flame retardant effect, their reaction products with plastic combustion performance is very poor.

Heat exchange interruption principle: take away part of the heat in the combustion process of the material, so that the material can not maintain the thermal decomposition temperature, and thus can not maintain the production of combustible gas, so the combustion self-extinguishing.

Such as: absorb the heat generated during combustion, play a role in cooling and slowing down the burning rate, such as aluminum hydroxide, the proportion of chemically associated water in its molecules is as high as 34%, this associated water remains stable at the processing temperature of most plastics, but in excess It begins to decompose at 200°C and releases water vapor. In addition, for every gram of aluminum hydroxide decomposed, 36 kcal must be absorbed.


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