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Polyolefin such as polyethylene material properties as people attach great importance to environmental protection, in the evaluation of, in addition to considering its flame retardant properties, low toxicity, low smoke polyolefin materials essential indicators. Environmentally friendly inorganic flame retardant magnesium hydroxide is a non-toxic, low smoke, thermal stability, good, because its surface is hydrophilic, while the polyethylene surface is hydrophobic, magnesium hydroxide surface modified in order to improve the surface physical and chemical properties, to enhance its compatibility with the polyethylene material, but also the need to improve the mechanical properties of the composite materials, such as flame-retardant polyethylene. The process of dry surface modification effects of modified temperature, the amount of modifier and modified time activation index of magnesium hydroxide, magnesium hydroxide results show that increasing the temperature of the modifier increased modified The dosage can be improved and modified time activation index of magnesium hydroxide. The optimal conditions for determining the magnesium hydroxide modified: modified temperature control at 80 ℃, magnesium stearate and KH570 in an amount of modifying agent, respectively, of 2.5% of the mass of the magnesium hydroxide powder to be modified, and 0.5%, change sex time to reach 3h. FTIR, XRD and SEM results showed that the activation of the magnesium hydroxide modified index up to the particle polarity is reduced more than 98%, significantly improved dispersion. The preliminary study also modified magnesium hydroxide / zinc borate complex system. Made under optimal conditions before and after modification of magnesium hydroxide and polyethylene blends,, magnesium hydroxide / polyethylene blend the tensile strength decreased with the increase in the amount of magnesium hydroxide to be added, after adding amount of 20% when compared with pure polyethylene material, modified before and after the magnesium hydroxide / polyethylene blend system tensile strength decreased by 8.22%, 1.98%, respectively. LOI values ??of the magnesium hydroxide / polyethylene blend system with the increase of the added amount of the magnesium hydroxide is gradually increased, an addition amount of 35%, the modified magnesium hydroxide / polyethylene the LOI values ??Blends were 26.0 , 24.6. DSC, TGA and SEM results show that the modified magnesium hydroxide / polyethylene blend system compared to non-modified magnesium hydroxide / polyethylene blend system has better thermal stability, processing properties and better with the polyethylene base compatibility. Under optimal conditions modified magnesium hydroxide / zinc borate composite system with polyethylene prepared Blends, in the case of the flame retardant added in an amount of 35%, changing the ratio of magnesium hydroxide and zinc borate flame retardant a tensile strength of the polyethylene material is maintained at between 19.0-20.6MPa; appropriate adjustment the proportion of the zinc borate, the oxygen index of the flame-retardant polyethylene, is still maintained at about 25.0 and the improved processing properties and thermal stability of the flame-retardant polyethylene, SEM The results show that the modified magnesium hydroxide / zinc borate composite system with the polyethylene base body having a good compatibility.
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