Hybrid XNBR composites with carbon and aluminosilicate nanofillers

The objective of the work was to investigate the possibility of simultaneous application of different types of nanofillers: graphene oxide with carboxylic groups and modified bentonite nanoparticles to carboxylated acrylonitrile–butadiene rubber (XNBR), and to determine the effect on the structural, mechanical and barrier properties of the composites. The composites were designed for use in protective clothing and gloves. Rubber compounds were crosslinked by a hybrid set with simultaneous use of sulphur (1.5 phr) and magnesium oxide (2.5 phr). Graphene oxide and bentonite particles were characterised by BET test method. The XNBR composites with nanofillers were studied in terms of structure (WAXS) and types of chemical bonds (FTIR), barrier properties against chemical substances (mineral oil) and swelling properties, as well as mechanical properties (puncture resistance, tear resistance, cut resistance, abrasion resistance, tensile strength). Simultaneous incorporation into XNBR of two types of nanofillers, bentonite in the amount of 1.0–4.0 phr and graphene oxide with carboxylic groups in the amount of 1.0–2.0 phr, affected positively the mechanical parameters. The most significant improvement was noted for the parameter specifying the puncture resistance, almost threefold improvement from 34 ± 2 N for unfilled XNBR composite to 91 ± 5 N for XNBR composite filled with 2 phr of bentonite (XNBR Bent. 2), or one and a half to 56 ± 5 N for XNBR composite filled with 2 phr of bentonite and 2 phr of graphene oxide (XNBR Bent 2 GO 2). The composites showed equally high resistance to penetration of the selected test chemical—mineral oil. The breakthrough time for XNBR composites without the nanofiller and containing differential amounts of nanofillers was very long and similar to that obtained for the reference sample (480 min).