The Effect of Surface Treatment of Bentonite on the Mechanical Properties of Polypropylene–Bentonite Composites

Bentonite filler was treated with different surface modifiers such as cetyl trimethyl ammonium bromide (CTAB), polyoxyethylene sorbitan monooleate (Tween 60), and compared with oleic acid. Polypropylene (PP) composites were prepared by blending with untreated and treated bentonite. The mechanical properties of the prepared composites were evaluated. It was found that the treatment with CTAB caused more deterioration to the mechanical properties relative to oleic acid, while the treatment with Tween 60 helped to keep the tensile yield unaffected (at 1% w/w) and to delay the loss in the elongation up to 10pph loading of the filler (at 0.1% w/w), in comparison with the oleic acid treatment.