Patent ID: 8048526

Claim:
A capped particle comprising: (i) one or more core particles wherein the core particle is an inorganic particle having a dimension of about 5 μm or less; and (ii) one or more multi-block copolymers attached to the inorganic particles, wherein the multi-block copolymer comprises a) at least one nonpolar polymer block having a Hildebrand solubility parameter less than 17.2 MPa 1/2 ; b) at least one first polar polymer block having a Hildebrand solubility parameter greater than 17.3 MPa 1/2 ; and c) at least one second polar polymer block having a Hildebrand solubility parameter greater than 17.3 MPa 1/2 ; wherein the nonpolar polymer block is interposed between the first polar polymer block and the second polar polymer block, the first polar polymer block is attached to the core particle, and at least a portion of the second polar polymer block is not directly attached to the core particle; so that when used in a lubricant to lubricate a metallic surface of a workpiece, the capped particle adheres to the metallic surface of the workpiece.