Dispersion of layered double hydroxides in poly(ethylene terephthalate) by in situ polymerization and mechanical grinding

An organic–inorganic hybrid compound constituted by a layered double hydroxide (LDH) with the hydrotalcite-type structure intercalated with dodecyl sulfate (LDH-DS), was dispersed in poly(ethylene terephthalate), PET, through chemical reaction or by mechanical treatment in an agate mortar or a ball mill. Exfoliation and dispersion of the inorganic-organic hybrid in the polymer phase was achieved by chemical processes. Mechanical grinding of the LDH-DS and PET mixtures only led to partial dispersion after long milling times, both for the PET-LDH composites and for the LDH-DS hybrid. In situ preparation of the polymer by chemical reactions yielded optimum exfoliation at low LDH-DS loadings. As a result, mechanical processes are not recommended for preparation of these composites.