One-Minute Guide to Deconstructing Four Major Flame Retardant Technologies

One-Minute Guide to Deconstructing Four Major Flame Retardant Technologies

Modern flame retardant technology has moved beyond the solo use of flame retardants, entering a new stage of deep synergy with advanced techniques. Through the precise design and transformation of their forms and modes of action, we are collectively driving the evolution of flame retardant efficacy towards high efficiency, environmental friendliness, and high performance.

I. Nanotechnology
In 1976, Japanese patents first reported that nanocomposites possessed flame retardant properties. However, it was only in recent years, with numerous studies by many international scholars on the thermal stability of nanocomposites, that research into their flame retardant performance truly began.

Studies found that when layered silicate nanocomposites contain less than 5% layered silicate (clay), they exhibit good thermal stability, with the peak Heat Release Rate (HRR) reduced by over 50% compared to the base material, without compromising other material properties. This indicates that polymer nanocomposites possess good thermal properties and can be used in flame retardant technology.
A mainstream method involves using nano inorganic flame retardants. These are typically nanocomposite materials composed of layered silicates, graphite, layered double hydroxides, carbon nanotubes, etc., such as nano-level epoxy resin, polystyrene, polypropylene composites.
Their advantage lies in requiring only a small addition of materials like layered silicates to maintain high thermal stability and safety of the overall material, thereby providing excellent flame retardant effects. While flame retardant performance improves, the trade-off can be a potential reduction in smoke suppression, and the environmental friendliness of nano flame retardants still warrants further research.

II. Microencapsulation
Microencapsulation involves enclosing flame retardants within tiny containers measuring from several micrometers to hundreds of micrometers, serving functions like protection and controlled release. Currently, microencapsulation is also a major trend in new flame retardant technologies.
A key feature of microcapsules is that the shell material does not chemically react with the encapsulated flame retardant. When the product encounters fire or high temperature, the capsule wall melts or ruptures, releasing the flame retardant—its principle is similar to that of medicinal capsules.

The shell materials mainly fall into two categories:

• Natural polymer materials: Animal glue, various proteins, starch, cellulose...

• Synthetic polymer materials: Polyvinyl alcohol, polyvinyl chloride, polyamide, polyester, epoxy resin...

A currently popular application is microencapsulated red phosphorus flame retardant. Through coating methods using inorganic compounds or organic resins, the red phosphorus is isolated from the external environment, overcoming issues like easy oxidation and moisture absorption, and avoiding the generation of toxic or harmful gases during processing.
It is now widely used in rubbers, thermoplastic resins (ABS, PA, PP, PC, PET, PBT, EVA, etc.), and thermosetting resins (epoxy, phenolic, etc.), often combined with magnesium hydroxide or aluminum hydroxide as flame retardant synergists to further enhance flame retardant capability.

III. Intumescent Technology
The development of intumescent technology and intumescent flame retardants (IFRs) within flame retardant systems has been very rapid in recent years, known for low smoke emission, no dripping, and non-toxic gases during combustion...

Intumescent flame retardant systems are generally composed of a carbonizing agent (char former), a carbonization catalyst, and a blowing agent (spumific). Among them, intumescent flame retardants are most extensively used in the coatings industry.
Intumescent Flame Retardants (IFRs) are mainly categorized into phosphorus-nitrogen flame retardants and expandable graphite. Phosphorus-nitrogen flame retardants are further divided into monomeric and mixed types.
The resulting char layer makes it difficult for heat to penetrate into the condensed phase, prevents oxygen from diffusing from the surroundings into the degrading polymer material, and also prevents the escape of gaseous or liquid degradation products from the material surface.

IV. Grafting and Cross-linking Modification Technologies
Grafting and cross-linking were originally techniques used for modifying polymer materials, such as for conductivity, high stiffness, and strength. In recent years, they have gradually been adopted to enhance the flame retardant properties of materials.

Generally, improving material flame retardancy via graft copolymerization is achieved by promoting char formation to achieve the flame retardant effect.
Because the grafted monomer can form an adherent inorganic insulating layer on the polymer surface, it enables the flame retardancy of the polymer. Additionally, causing cross-linking within the polymer material itself, or within the condensed phase of its thermal decomposition products, can simultaneously reduce the generation of flammable volatiles, thereby improving the material's flame retardant performance.

For 21 years, Yinsu Flame Retardant has focused on one thing – keeping "fire" outside the material.
From the initial bag of red phosphorus to today's "toolbox" of four major flame retardant technologies, Yinsu has witnessed the industry's shift from "indiscriminate addition" to "precise reaction."
Now, we have transformed the technologies discussed in this article—intumescent charring, gas phase inhibition, cross-linking sealing, nano-barriers...—into customizable "modules," integrated into every flame retardant formulation tailored for our clients:

• In cables, red phosphorus flame retardants can achieve LOI > 34

• Flame retardant additive loading reduced by 15%

• Halogen-free, low smoke, non-blooming, compliant with REACH/ROHS in one go

Fires vary infinitely. Yinsu has a thousand solutions.
Let us design the next "safety lock" – Yinsu Flame Retardant provides a customized cost-reduction plan within 24 hours, stopping fire at its source!