In industrial production, expanded graphite can be used as flame retardant, play the role of heat insulation flame retardant, but when adding graphite, to add extensible graphite, so as to achieve the best flame retardant effect. The main reason is the transformation process of expanded graphite and expandable graphite. Today, WE will talk about the flame retardant process of expanded graphite and expandable graphite: After high temperature expansion, expansible graphite can be made into expanded graphite and expandable graphite under high temperature expansion, the volume increases rapidly, so the density of expandable graphite expansion after generally smaller than natural graphite hundreds, specific surface area is increased greatly, with the increase of material of the specific surface area, surface free energy will increase quickly, make its surface activity increases, the surface adsorption force increase, So the lubricity of expandable graphite is improved, the permeability of gas and liquid is reduced, but its chemical properties are the same as natural graphite, almost not corroded by any chemical substances, so the graphite seal made of good sealing, high temperature resistance, wear resistance, is an indispensable raw material for the production of mechanical seals.
To understand the flame retardant process of expansive graphite and expansive graphite, it is necessary to understand the difference between expansive graphite and expansive graphite.
1. Expandable graphite is not expanded and has the characteristics of rapid expansion in case of high temperature.
Expansive graphite and expansive graphite are two different products, expansive graphite is the product of expansive graphite after high temperature heating, expansive graphite because of the large gap after expansion, has good adsorption function, can be used as a product to clean up pollutants in water.
After expansion, the thermal conductivity of the material can be reduced to achieve the effect of flame retardant. If the expanded graphite is directly added, the structure of the carbon layer formed after combustion is certainly not dense.
2. expanded graphite is the process of expansion has taken place, large volume.
Post time: Nov-19-2021