Magnesium hydroxide(MH) LXF-M599 is a high-purity magnesium hydroxide powder with a regular hexagonal crystal morphology, synthesized using a unique process. It features high content, good whiteness, regular crystal morphology, small particle size, uniform particle size distribution, good dispersion, and low impurities. Magnesium hydroxide(MH) LXF-M599 exhibits thermal stability up to 340℃ and possesses triple functions of flame retardancy, smoke suppression, and filling. It can synergistically interact with various phosphorus and nitrogen, bromine and antimony, and phosphate ester flame retardants.

I. Basic Information

Molecular Formula: Mg(OH)₂

Molecular Weight: 58.32

CAS NO.1309-42-8

Melting Point: 350℃

Solubility: 1.2 mg/100 mL

Flash Point: Non-flammable

II. Product Specifications

Appearance: White powder

Mg(OH)₂>99.0%

CaO≤0.20%

Fe²⁺<0.005%

CI≤0.05%

H₂O≤0.30%

Specific Surface Area: 4-6 g/m²

Whiteness>99%

Particlesize (D50)≤1.5μm

III. Flame Retardant Mechanism

Magnesium hydroxide (Mg(OH)₂) is a commonly used inorganic flame retardant. Its flame retardant mechanism is mainly based on decomposition endothermic cooling and char formation isolation, specifically reflected in the following aspects:

1. Decomposition Endothermic

This is the most important flame retardant mechanism of magnesium hydroxide. The decomposition temperature of magnesium hydroxide is approximately 300-340℃, a temperature range that precisely covers the decomposition temperatures of most polymer materials (such as PP, PE, TPE, etc.). When the material is heated, magnesium hydroxide undergoes endothermic decomposition, absorbing a large amount of heat, effectively lowering the surface temperature of the material, slowing down the thermal decomposition rate of the polymer material, and inhibiting the generation of combustible gases. The water vapor produced during decomposition can dilute the concentration of oxygen and combustible gases in the flame zone, while the water vapor itself does not participate in combustion, thus acting as a gas-phase flame retardant.

2. Charring Mechanism: The magnesium oxide (MgO) generated after decomposition is a highly thermally stable inorganic substance that forms a dense solid char layer or inorganic protective layer on the material surface. This barrier can prevent the diffusion of external oxygen to the substrate and simultaneously hinder the escape of combustible gases generated by internal decomposition into the flame zone. This protective layer can also reflect some heat, slowing down the heat feedback effect and preventing further flame spread.

3. Smoke Suppression and Non-Toxic Properties

Unlike traditional halogenated flame retardants (which produce large amounts of black smoke and toxic, corrosive gases), magnesium hydroxide is a halogen-free flame retardant. It does not produce large amounts of smoke during combustion, and its decomposition product, MgO, can adsorb smoke particles, significantly reducing the smoke density of the material. The decomposition products are water and magnesium oxide, both of which are non-toxic and non-corrosive, meeting environmental protection requirements. In certain polymers containing oxygen-containing functional groups (such as PET, PBT, and PA), the alkaline MgO surface generated from the decomposition of magnesium hydroxide can catalyze the cross-linking of the polymer into carbon. Compared to simple physical insulation, this synergistic effect of "charring + heat insulation" more effectively prevents flame propagation.

IV. Application Areas

Wires and cables, engineering plastics, unsaturated resin materials, insulating materials, electronic wires, new energy charging pile wires, rubber, electronics, lubricant additives, adhesives, coatings, food, pharmaceuticals, etc.

V. Packaging and Storage

Packaging: 20kg/bag, packaging can be customized according to user requirements.

Storage: Store in a well-ventilated and dry place.

VI. Safety and Handling Information

Refer to the Safety Data Sheet for safety, toxicity, and handling information.

Since magnesium hydroxide is an inorganic filler, its compatibility with organic polymers is poor. To achieve good flame retardant effects (typically, the addition amount needs to reach 50%-60%), The above factors often severely affect the mechanical properties of materials (such as a decrease in impact strength and elongation at break). Therefore, in practical industrial applications, magnesium hydroxide is usually surface modified (e.g., by using silane coupling agents or titanate treatments) or compounded with flame retardant synergists such as red phosphorus, organosilicon, and nano-clay to improve the processing and mechanical properties of the material while maintaining its flame retardant properties.