Surface modification of inorganic fillers

In general, surface modification of inorganic fillers can be carried out by utilizing physical or chemical interactions between the fillers and the modifiers. The resultant bonding is often a mixture of secondary and chemical bonds. There is no evident difference between the treatments of micro-particles and nanoparticles, except that it is quite difficult for the surface modifiers to penetrate into the tightly bonded nanoparticle agglomerates, especially in the case of physical treatments such as surfactant treatment and polymer encapsulation. 

There has been a growing interest in the surface modification of inorganic oxide substrates with covalently bonded polymer phases for a variety of practical applications, such as filler-polymer control in polymer composites, support packing for liquid and gas chromatography, biocompatible surfaces, colloid stability and modified inorganic membranes, and for fundamental studies of interfacial phenomena. 

The aim of the study was to assess the impact of surface modification of magnesium hydroxide on the flammability and mechanical properties of composites PE-HD/ MDH. The surface treatments can decrease the surface energy of inorganic fillers and improve the dispersion of an inorganic filler in a polymer matrix. The mechanical performance and flame retardancy of the PE-HD/MDH composites largely depend on the dispersion of fillers in the polymer matrix and the adhesion between the filler particles and polymer matrix. Different surface treatments of commercial magnesium hydroxide obviously affect interactions between fillers and the polymer matrix. 

The surface modification technique of inorganic fillers directly affects the filling modification. The common surface modification methods can be classified into three types inorganic filler pretreatment, blending, and masterbatch methods. 

However, the surface modification of the inorganic filler is at least as important as the aspect ratio. 

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