A new strategy for preparing high oil content PAO40@HMCs microcapsules for improving tribological properties of PA6 composites

Enhancing the tribological characteristics of polyamide 6 (PA6) represents an effective strategy for extending the service life of self-lubricating PA6 composites. In this investigation, hollow mesoporous carbon spheres (HMCs) with an average diameter of 10 μm were synthesized using the template method, and the crucial factors influencing HMCs preparation were thoroughly examined. Successful synthesis of polyalphaolefin oil-containing microcapsules (PAO40@HMCs) was achieved, utilizing HMCs as microcontainers and PAO40 lubricant as the core material. The self-lubricating PAO40@HMCs microcapsules exhibited a notable oil content of 76.0 wt%. The tribological properties of the prepared self-lubricating PA6 composites were significantly better than those of pure PA6. When the content of PAO40@HMCs microcapsules in the composite reached 7 wt%, the coefficient of friction (COF) for the PA6 composite decreased by 87.9% (from 0.420 to 0.051), and the wear loss was reduced by 80% (from 0.115 to 0.023 g/0.5h). Through an analysis of the morphology and transfer film of the wear surface and friction pair, it was evident that microcapsules played a pivotal role in enhancing the self-lubricating properties of PA6 composites.