After the flame retardant modification of PA6, its use range will be greatly increased, and it will be extended to the fields of electronics, electrical appliances, communication, aviation, etc., making the application of PA6 more extensive, and greatly increasing the flame retardant mechanism of PA6 demand. PP Modified Material Supplier will give you a detailed explanation.
(1) During the combustion process, as the temperature rises, some gases are generated. These gases are denser than air and cover the surface of the object to form a barrier effect, such as a bromine-based flame retardant and a chlorine-based flame retardant. In particular, the use of such a flame retardant in combination with Sb2O3 produces a better effect, the mechanism being the formation of a more dense gas such as SbX3.
(2) After the flame retardant is burned, a substance is produced to dehydrate or clarify the surface of the plastic. A typical example is a nitrogen-based flame retardant, such as melamine, which produces HNO3 at high temperatures to clarify the plastic. Phosphorus-based flame retardants are also such, mainly phosphoric acid eventually forms polyphosphoric acid, which ultimately contributes to the carbonization of the plastic, thereby isolating oxygen. The same is true for the flame retardant mechanism of red phosphorus, and the flame retardant effect is better than that of the phosphorus organic flame retardant. The mechanism is that red phosphorus has higher phosphorus content and produces more polyphosphoric acid, but it also has a clear disadvantage. Color, generally red phosphorus flame retardant materials are brown, color matching is more difficult.
(3) Another kind of flame retardant, mostly water, and inorganic substances, mainly in the process of combustion, dehydration, generating water vapor, diluting the air while cooling the object, such as water and aluminum hydroxide.
The main principles of flame retardant selection:
(1) Note the melting point of the PA6 Compound. The melting point of the flame retardant must be greater than the melting point of the substrate to prevent the flame retardant from failing during processing.
(2) Determine the required flame retardancy and other mechanical properties of the material based on the specific use of the PA6 material.
(3) Consider the application of other additives when selecting flame retardants.
(4) When glass fiber reinforced flame retardant, only halogen phosphorus flame retardant can be selected, nitrogen flame retardant can not be selected, and flame retardant dispersant should be added at the same time.
(5) Consider the color requirements of the product. For example, the color of red phosphorus flame retardant will be brown.
The following are counterproductive:
(1) Halogen-based flame retardants and red phosphorus should not be mixed with silicone.
(2) Bromine-based flame retardants should not be added with calcium carbonate and magnesium carbonate.
Xinyite reminds you that, overall, the Flame Retardant Nylon PA6 Granules has changed a lot in performance. Mainly reflected in the decline of mechanical properties, friction resistance, heat resistance has a certain decline, but the processing fluidity has improved.