Preparation of ionic liquid@SiO2 nanocapsules for improving self-lubricating performance of PA6 composites

A novel high temperature resistance ionic liquid@SiO2 (IL@SiO2) nanocapsules were successfully prepared in order to meet the high temperature processing requirement. The average diameter and the loading capacity of as-obtained IL@SiO2 nanocapsules were about 420 nm and 44.7 wt% respectively. The IL@SiO2 nanocapsules showed excellent thermal stability with a 340 degrees C initial thermal degradation temperature. The frictional and wear properties of PA6 composites containing IL@SiO2 nanocapsules under different friction temperature were studied systemically. Self-lubricating PA6 composites with 3 wt% IL@SiO2 nanocapsules showed the optical tribological propertied. The corresponding friction coefficient of PA6 composites reduced by 38.9%, and the wear rate also showed a 60.7% decrease compared with pure PA6. Unlike most microcapsules, the addition of nanocapsuels did not cause an undesirable and obvious decrease in mechanical properties of PA6. Anti-wear and friction-reduction mechanism were depth analyzed, and results revealed that IL core and SiO2 wall in nano-capsules synergistically contribute to improve self-lubricating performance of PA6 composites.

Automated summary

A novel high temperature resistance IL@SiO2 nanocapsules were successfully prepared and their friction and wear properties in PA6 composites were studied. The addition of IL@SiO2 nanocapsules reduced the friction coefficient and wear rate without affecting the mechanical properties of PA6. The synergy between the IL core and SiO2 wall in the nanocapsules improved the self-lubricating performance of the PA6 composites.