Surface modified microcapsules with improved interfacial adhesion and high thermal stability utilized for the tribological application of epoxy composites

Self-lubricating microcapsules embedded in the epoxy composites exhibit prominent friction-reduction and anti-wear effects. However, the inferior interfacial compatibility between the microcapsules and the matrix deteriorates mechanical properties of the composites greatly. In this study, DMS@PS-TMP-A microcapsules with a molecularly uniform organic-inorganic hybrid shell of styrene and methacryloxypropyltrimethoxysilane copolymer (PS-TMP) and dimethylsiloxane oil (DMS) as core were fabricated via one pot synthesis. The mechanical properties of DMS@PS-TMP-A/EP composites were improved by surface modification of the microcapsules with the tensile strength and modulus of the 15 wt%DMS@PS-TMP-A/EP composites increased by 46.04 % and 63.06 % with respect to the corresponding unmodified sample. Due to the high bond-energy Si-O motifs evenly distributed in the shell, the thermal decomposition temperature of the corresponding microcapsules was increased by 38.5 °C. Meanwhile, the 15 wt%DMS@PS-TMP-A composites showcase a reduction of 62.69 % and 95.48 % in friction coefficient and wear rate relative to pure EP samples and the wear mechanism of the composites varied from fatigue to adhesive wear.