flame retardantRecently Xiaobian often encounter similar problems, today we come to popularize:

First, the combustion process is complex.

There are three conditions for combustion: combustible, combustion-supporting, reaching the ignition point. Because combustibles have a variety of phases (gaseous, liquid, solid, liquid has different vapor pressures, solid has tight and loose points), the concentration and diffusion of combustion improvers exist, and the ignition point exists high and low, so the combustion process is very complicated. This involves open burning and smoldering.

In addition, the spread of fire is also part of the content of combustion. Therefore, there are also many combustion test modes, such as vertical combustion, horizontal combustion, glow wire test, etc.

Second, the results and hazards of combustion are complex

Burning, high temperature damage, smoke hindering escape and smoke poisoning.

Third, the flame retardant mechanism is complex

First of all, it involves gas phase flame retardant and condensed phase flame retardant. The gas phase involves the generation of flame retardant gases and the flame retardant reaction process. The condensed phase is involved in the charring process and charring quality. From the perspective of flame retardants, many flame retardants are involved, including inorganic flame retardants and organic flame retardants, and organic flame retardants include halogen flame retardants and halogen-free flame retardants. In addition, the synergy and compounding of different flame retardants is also an important content. The complexity of flame retardants is also reflected in the high loading of flame retardants, which poses challenges to the mechanical properties and other properties of flame retardant materials, such as heat resistance and toughness.

Fourth, complex processing applications

When flame retardant is modified by melt blending, there is often a problem of thermal stability of flame retardants, and thermal stability and flame retardancy are an inherent contradiction. In addition, thin products, such as spinning, non-woven materials, flat filaments, films, etc., often have higher requirements for the particle size and content of flame retardants. Such as intumescent flame retardant flame retardant PP flat wire, because the coating particle size is larger, flat wire stretch often broken wire. When the PE cable material is flame retardant with aluminum hydroxide, if the aluminum hydroxide is not well dispersed or the surface is subjected to large shear, too high filling amount of flame retardant will cause powder to fall off and form mold scale. When the flame retardant light diffusion PC of sulfonate PTFE is extruded, if PTFE coating is poor and PTFE agglomeration occurs, pitting will occur on the surface of the extrudate.

Fifth, complex flame retardant regulations

Flame retardant modification involves not only fire safety regulations, but also flame retardant toxicity and environmental pollution regulations, such as IEEE He UL's fire regulations and flame retardant grade certification, ROHS directive and REACH certification, as well as various regulations of governments and related enterprises around the world.