(88e) Surface Modification of Carbon Hard Sphere Via Surface Initiated Atom Transfer Radical Polymerization

Lubricants play an integral role in the operation of several technologies and in biology also, ranging from moving parts in machinery to the biolubrication of artificial joints. We have found that a colloidal dispersion consisting of easily synthesized highly spherical and uniform carbon particles coupled with surface grafting of polymers that result in a stable dispersion and provides low friction coefficients and excellent surface wear protection. The covalent functionalization with the polymer graft is achieved through the surface initiated atom transfer radical polymerization (SI-ATRP). We hypothesize that these particles would decrease the overall friction coefficient compared to ungrafted particles. These particles use a rolling mechanism similar to nano –or microscale ball bearing under confinement. The effect of several parameters of lubrication including the thickness of the grafted polymer layer, type of polymer grafted, along with the size of the carbon particles will be presented. These parameters listed would be optimized to generate the lowest frictional coefficient. Broader applications beyond just lubrication include adsorbents, and reinforcement in composite materials