Factors affecting the dispersion of organo-layered double hydroxides in a polyolefin matrix

The results reported in this work regard on nanocomposites based on low density polyethylene (LDPE) and layered double hydroxides (LDHs). The effect of processing parameters and type of LDH modifier on the organo-LDH dispersion in the LDPE matrix was investigated. It was found that the intercalation of polymer chains is hindered when surfactant molecules form a bilayer structure, like in the case of LDH-stearate, whereas mono layered organo-LDHs were successfully dispersed into the polymer matrix. Moreover, the addition of a compatibilizer (PE functionalized with maleic anhydride) promoted the polymer chain intercalation, but was also responsible of a partial particle aggregation. The optimization of processing parameters, in the case of LDPE/PEMAH/Perkalite F100 nanocomposites, favoured the intercalation of polymer chains between the double hydroxide layers as evidenced by XRD analysis and supported by TEM.