Registered office:

SUITE 1503, 15/F, Carnival Commercial Building, 18 JavaRoad, North Point, HONGKONG

Factory Address

Work-I - [NATURAL BRUCITE] - Dandong City, Liaoning Province, China; Work-II - [Precipitated Mg(OH)2] - Lanzhou, Gansu Province,China

Contact with us
+86 18209311736

Halogen Free Flame retardant

MDH (Natural Brucite Powder) 

MDH (Precipitated Magnesium Hydroxide) 

ATH (Aluminum Hydroxide) 


KMT Polymer Flame Retardant Solutions

KMT Industrial Ltd., specializes in researching, producing, and selling brucite powder, precipitated magnesium hydroxide, and other flame retardant products. We have one R&D center, two plants, dozens of patents, and the plants are ISO9001 certificated, Dun & Bradstreet code 554405380.

All the products comply with RoHS requirements and have REACH registration. KMT product sells to all over the world, and we have warehouses and agencies in the United States, Germany, Spain, Turkey, and India. 。

R&D Center: Lanzhou City, Gansu Province Global Business

Office: KMT Industrial (HK) Limited

Natural Brucite Production Factory: Dandong, Liaoning Province

Precipitated Magnesium Hydroxide Production Factory: Dingxi, Gansu Province

KMT R&D Center Equipment

KMT R&D center equipped with the reactor, ball mill, vacuum drying oven, laser diffraction particle size analyzer, whiteness meter, high-speed mixer, twin-screw extruder, Banbury, flat vulcanizing machine, sample making machine, universal testing machine, melt flow tester, oxygen index meter, combustion test instrument, our lab not only used for our R&D, but can also make compounds and support test for our customer.

KMT Technical Support

We can provide FR PVC compounds and HFFR cable compounds basic formula;

We can provide B1/A2 FR ACP turnkey project;

We can make lab trial for our customer formulation and test it according to different standards;

We can help support all kinds of compound testing and analyze;

Our FR expert team is ready for your consultation at any time.

KMT Main Product Series

PM Series: Precipitated Magnesium Hydroxide

------Manufactured in Dingxi Factory

PM series precipitated magnesium hydroxide are patent product developed recent years. Their performance could compete with high level magnesium hydroxide produced by Austria, Japan, Russia. It could be applied to produce low smoke zero halogen flame retardant cable and wire. Our customers includes world top level cable companies such as Prysmian, Nexans, LS Cable…

B Series: Natural Brucite Powder

------Manufactured in Dandong Factory​

The production of natural Brucite is started in the year 2000. B series Brucite has both high purity and high whiteness characteristics. We can tailor-made products in different purity, whiteness, particle sizes, and surface treatment based on customer’s requirements. B series Brucite is widely used in PVC cable, HFFR cable compound, flame retardant panel, aluminum composite panel, flue gas desulfurization, wastewater treatment, magnesium fertilizer, etc.

A Series: Aluminum Hydroxide

------Manufactured in Dingxi Factory​

Virtually all the aluminum hydroxide used commercially is manufactured by the Bayer process which involves dissolving bauxite in sodium hydroxide at temperatures up to 270 °C (518 °F). The waste solid, bauxite tailings, is removed and aluminum hydroxide is precipitated from the remaining solution of sodium aluminate. Aluminum Hydroxide can be used as a halogen-free flame retardant due to its well-distributed granularity, good stability, non-toxic and non-polluting.

KMT Magnesium Hydroxide

Flame Retardant Mechanism of Magnesium Hydroxide

Mg(OH)2 ———> MgO+H2O

When the temperature reaches 340℃, magnesium hydroxide starts decomposing and generating water and Magnesium oxide. The water will absorb heat and dilute the oxygen content in the air to stop the fire, while the magnesium oxide will adhere to the surface of the combustible material to stop the fire and also absorb toxic gas and smoke produced during the fire.

KMT Precipitated Magnesium Hydroxide

KMT Industrial high purity precipitated MDH is manufactured according to the below chemical reaction:

                MgCl2 + 2NH3 ▪ H2O → Mg(OH)2 ↓ + 2NH4Cl

First, we extract its main raw material directly from the saltwater to prepare the Magnesium Chloride solution, then the solution will go through a purification process to become the highly purified solution. After we get purified Magnesium Chloride solution, along with ammonia, two solutions will be added into the reactor and react under specific temperature. We will get coarse precipitated Magnesium Hydroxide.

Finally, based on customer request, coarse precipitated Magnesium Hydroxide shall go through hydrothermal modification and milled into different particle sizes’ powder and coated with different additives. The entire production process is environmentally friendly and pollution-free. Ammonium water is recyclable, and no toxic matter is generated. That is what KMT industrial insisted on from the very beginning.

Table 1 PM Series MDH Technical Data








0.40% or ≤0.20%







Table 2 PM Series MDH Particle Sizes


Median Particle Sizes (D50)


PM3 Grades

2.5-3.5 μm


Low smoke zero halogen flame retardant materials

PM5 Grades

1-2 μm

Other customized Grades are also available

Table 3 PM Series MDH Coating



PM3, PM5



Single Silane or composite additives coated


Proprietary composite additive coated

Table 3 shows available additives for coating. It makes the powder easy to disperse in the polymer and provides better mechanical properties. Silane and stearic acid coated MDH can improve the dispersity, flame retardant performance, and by adding special additive, the processing rheology is also improved because the compound viscosity is lowered. KMT also developed proprietary coating such as SL, SN, SM. Compared with silane coated MDH, SL, SN, SM coated MDH has a better elongation, MFI, and better charing.

KMT Precipitated Magnesium Hydroxide---Comparison Test Data

To identify the performance of PM series MDH, the KMT R&D center conducted several tests by adding different grade MDH into the EVA-based formula. On the one hand, to see the performance of PM3SL, PM5SN, and PM5SM, on the other hand, to compare KMT PM series MDH with MDH made by American, Japanese, and Russian company.

The results show that:

1. In terms of MFI, PM3SL has better performance than PM5SN.

2. KMT PM series can be an alternative for American, Japanese, Russian MDH.

3. PM series can all pass the UL94 V-0 test (3.2mm), see table 5.

Table 4 Polyolefin Test Formulation

EVA 7470k


Compatilizer LR508

Antioxygen 1010






UL94 Combustion Test Report

Table 5 UL94 Combustion Test









American MDH




Japanese MDH





Russian MDH



Differences of Flame Retardant ATH & MDH

1. When being heated, MDH and ATH both generate water and metal oxide. Water absorbs heat, and metal oxide covers the surface of polymer. But MgO can absorb more acid than Al2O3.

2. Magnesium hydroxide (MDH) degrades at 340℃, 140℃ higher than Aluminum Hydroxide (ATH) does, so MDH is better for plastics required high processing temperatures.

3. MDH dissociation energy is 1.37kJ/g; ATH dissociation energy is 1.05KJ/g, and the thermal capacity of MDH is 17% higher than ATH also. So MDH has higher flame retardant efficiency.

4. Magnesium hydroxide with more carbonization can reduce more smoke.

5. MDH particle is softer than ATH, so less abrasion will happen during the compounding process which is good for the compounding machine.

KMT Natural Brucite

Natural Brucite is the mineral form of magnesium hydroxide. With abundant Brucite Ore resources, Dandong KMT is committed to producing Brucite powder, and its annual capacity shall reach 100,000MT.

Compared with high purity magnesium hydroxide, Brucite powder is widely used as a high filling flame retardant in the wire and cable industry, such as filling compounds, bedding compounds, and sheathing compounds for PVC cable, low smoke zero halogen cable.

Table 6 shows the composition of Brucite powder.

Table 6 KMT Natural Brucite powder Technical Data















Table 7 B Series MDH Particle Sizes


B-3 series

B-3.5 series

B-10 series

Median Particle Sizes   (D50)





PVC compounds, polyolefin cable compounds, TPO and PVC roofing membranes…

Bedding compounds,  B1/A2 ACP…


Silane, Stearic acid, other customized additive



KMT® for XK-Brucite Series used in Aluminum-Composite Panel

KMT® for LSZH Flame Retardant Cable Industries

KMT® for Mineral Filler

KMT® for Thermoplastic PVC- and polyolefin-based Compound

KMT® XK-series MDH as ATH Substitute and Synergy

KMT® for Engineering plastics Compounds

KMT® for Flame Retardant Coating

Other Application

KMT Industry's Services Always Go Extra Mile

KMT Industry’s goal is to let you sit back and relax. We take care of all the dirty works, including trade stuff,  clearance and logistics, etc. Our consultant will keep you informed of the trade progress throughout.

Formular and polymer test Available

If you want a basic formula to compare with competitors grades, we can support it in our lab.

Lighting Fast Delivery

Normal grades have the inventory to support fast delivery.

Start With Low MOQ

If you want to have a trial test, we support a minimum order quantity of small kgs for the first order.

Arabic AR Dutch NL English EN French FR German DE Hindi HI Irish GA Italian IT Korean KO Persian FA Portuguese PT Russian RU Spanish ES