High‐density polyethylene/attapulgite (ATP) nanocomposites: Effect of the organophilization of ATP on the structural, mechanical, and thermal properties

Abstract

Organic–inorganic nanocomposites have attracted great interest due to the remarkable improvement in mechanical properties when compared to neat polymers. The use of a low‐cost nanofiller added to good properties becomes attractive to the industry. Attapulgite (ATP) is a very interesting nanofiller alternative, especially when used with polyolefins, as in the case of high‐density polyethylene (HDPE). However, this system is not simple, as HDPE is a nonpolar polyolefin that can cause low dispersion of ATP. One way to increase the interaction between these phases is the surface modification of ATP. In this work, the surface of ATP was modified using trimethylamine hydrochloride. HDPE/ATP nanocomposites with 1 and 5 wt% of raw ATP (ATPr) or organophilic ATP (ATPo) were prepared by extrusion. The effectiveness of the organophilization process of ATP was evaluated by X‐ray diffraction, mechanical properties (Shore D hardness and tensile test), and thermal properties (thermogravimetric analysis and differential scanning calorimetry), contact angle, and scanning electron microscopy. In the HDPE/ATPo nanocomposites, it was possible to observe an improvement in mechanical and thermal properties when compared to HDPE/ATPr nanocomposites. The organophilization of ATP promoted a greater interaction between the phases, contributing to a better dispersion of ATP in the HDPE matrix.