Antibacterial GO@SiO2 nanofluids/natural rubber composite films with and simultaneously enhanced mechanical strength and elongation at break: A new strategy beyond nanofillers

Developing nonchemical cross-linked natural rubber (NR) latex gloves with antibacterial properties and simultaneously enhanced mechanical strength and elongation at break is challenging. In this study, liquid-like silica (SiO 2 ) nanofluids (SiO 2 nfs) with hard SiO 2 cores and soft organic molecule shells are synthesized and then self-assembled with graphene oxide (GO) via electrostatic interactions to create GO@SiO 2 nfs hybrids, which are blended with NR latex. Strong hydrogen bonding and electrostatic interactions between NR latex particles and GO@SiO 2 nfs hybrids form physically cross-linked GO@SiO 2 nfs/NR composite films. The rigid GO in the hybrids provided reinforcement, while the vicious SiO 2 nfs facilitated the energy dissipation during stretching. This synergy results in simultaneous improvements in the mechanical strength and elongation at break of the GO@SiO 2 nfs/NR composite films. Their tensile strength increased by 95.2% compared with pure NR films and by 20.6% compared with GO/NR composite films, and the elongation at break improved by 27.8% and 19.4%, respectively. Furthermore, the presence of quaternary ammonium cation in SiO 2 nfs conferred excellent antibacterial efficacy against Escherichia coli and Staphylococcus aureus to the GO@SiO 2 nfs/NR composite films. These results offer valuable insights for the development of high-performance, nonchemical cross-linked NR latex products.