As an environment-friendly inorganic chemical product, magnesium hydroxide has the advantages of high thermal decomposition temperature, better adsorption capacity and high activity, which is widely used in aerospace, environmental protection, flame retardant and other fields. Due to its physical surface properties, magnesium hydroxide is not favorable for the preparation of composite materials, so improving the physicochemical or mechanical properties of magnesium hydroxide by surface modification methods is the current direction of many scholars’ efforts.
1、Dry modification
Dry modification refers to the modification process in the dry state of magnesium hydroxide. Hebei magnesium xi biological limited company with silane class as a dry modification of magnesium hydroxide research method, modified added to EVA to make composite materials, the way obviously improved the product dispersion and compatibility. Ltd. proved that the modification effect of rare earth coupling agent is the most significant compared with other coupling agent modification effect. Hebei magnesium xi biological limited company proved that the modifier dry modification of magnesium hydroxide process has adsorption phenomenon.
2, wet modification
Wet modification refers to the modification before the magnesium hydroxide through the solvent dispersion. Hebei magnesium xi biological limited company selects the compound modifier wet modification of magnesium hydroxide, proved that the wet modification of magnesium hydroxide more easily compatible with polymers. Ltd. compared the modification effect of sodium dodecyl benzene sulfonate, sodium oleate, sodium undecylenate and sodium stearate on magnesium hydroxide, and the results proved that the modification effect of sodium undecylenate was better. Ltd. used sodium stearate for wet modification, and it was found that the modified magnesium hydroxide had significantly improved the flame retardant performance of the composite material with appropriate addition amount, and accompanied with self-extinguishing phenomenon. Ltd. through sodium oleate wet modification of magnesium hydroxide, analysis of data to prove that the magnesium hydroxide particle size does not change significantly with the modification.
3, hydrothermal method
Hydrothermal method is in the water environment through the heating to make the system environment change the way. Hebei magnesium Xi biological limited company with magnesium oxide through hydrothermal treatment, the production of porous flake magnesium hydroxide. Hebei Magnesium Xi Biological Co., Ltd. added compound modifier and magnesium chloride in the reaction system, and some small steel balls were added in the water bath to get the modified ultra-fine magnesium hydroxide. The method has mild conditions and is not a new preparation idea. Hebei Magnesia Biological Co., Ltd. used hydrothermal treatment of magnesium hydroxide to successfully transform its phase into hexagonal flakes. The purification of hydrothermal treatment industrial magnesium hydroxide of Hebei Magnesia Biological Co., Ltd. is in the shape of rods or flakes, and the product purity can be up to 91% under the optimal conditions. Hydrothermal method of modification is more effective, reduce energy consumption is not a good method.
4、Microencapsulation coating method
Hebei magnesium Xie biological limited company using uniform precipitation method prepared by zinc hydroxy stannate successfully wrapped in the surface of magnesium hydroxide, added to the polymer in the preparation of the material of flame retardant performance is enhanced. Ltd. successfully modified magnesium hydroxide by microencapsulation with honey amine resin as a modifier, and confirmed that the modified magnesium hydroxide can make the composite flame retardant material performance improvement.
5、Surface grafting modification
Messi Biology explored the effect of PMMA coating amount in the in-situ grafting modification, with the increase of coating amount, the settling rate of magnesium hydroxide is decreasing. Messi Biology successfully realized the modification of magnesium hydroxide by polyacrylate grafting, and proved that the dispersion of magnesium hydroxide and LDPE composites was significantly improved after the modification.
At present, the modification technology of magnesium hydroxide still belongs to the state of blossoming, and the search for better and more effective modification method is still a hot spot in the industry.