| In order to overcome the disadvantages of the long synthesis route,high cost and poor compatibility with polymers of the magnesium hydroxide in the traditional preparation techniques,magnesium hydroxide nanowhiskers were synthesized by alkaline mixture injected into magnesium chloride solution in the presence of surfactant.The influence of different surfactant on dispersity and morphology was investigated.Magnesium hydroxide nanowhiskers had better dispersity using acrylic acid as surfactant by SEM analysis.Under atmospheric pressure,the influences of dosage of acrylic acid,reaction temperature and concentration of sodium hydroxide on dispersity,crystal shape and yield of magnesium hydroxide nanowhiskers were studied.The product was analyzed by the SEM,EDS,TEM, XRD and FT-IR.Optimum conditions for synthesis of Mg(OH)2 were obtained as followings:the concentrations of magnesium chloride and sodium hydroxide are 2mol/L and 2.2 mol/L respectively,the dosage of acrylic acid is 3%(mass ratio to magnesium chloride) and the reaction temperature is 10℃.The magnesium hydroxide nanowhiskers so prepared have the length of 50～150nm and the diameter of 8～15nm,which are well-crystallized and have uniform size distribution with high purity up to 98.91%.The preparation technology shows the advantages of low cost,simple production process and low energy consumption,thus overcoming the disadvantages of high equipment requirement,great technical difficulties,high cost and lack of safety in traditional hydrothermal method.To improve the compatibility between magnesium hydroxide nanowhiskers and polymers,in this research emulsion polymerization method was used to prepare the inorganic-organic core-shell composite.Acrylic acid-modified magnesium hydroxide nanowhiskers were encapsulated by using acrylic acid-modified magnesium hydroxide nanowhiskers as seeds and MMA or St as monomer.Polymerization process between acrylic acid-modified magnesium hydroxide nanowhiskers and monomer(MMA and St) was preliminarily explored.The influences of dosage of acrylic acid-modified magnesium hydroxide nanowhiskers,initiator,monomer and reaction temperature on the monomer conversion rate were systematically studied.The Orthogonal experiment shows the reaction temperature affects the diameter of composite particles most and the dosage of initiator affects the monomer conversion rate most.PMMA/AA-Mg(OH)2 and PS/AA-Mg(OH)2 nanocomposite were characterized by FT-IR,SEM and TEM.The result indicates MMA and St reacted with AA-Mg(OH)2 and the composite particle has a core-shell structure with the diameter of 100-500nm.After polymerization,the morphology of the composite has turned into spherical.
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