Multi-end-functionalized polymers: additives to modify polymer properties at surfaces and interfaces

An ongoing challenge in polymer science is the preparation of materials with specific surface properties which differ from that of the bulk, for example, hydrophobicity, wettability, chemical resistance, adhesion, or biocompatibility, while retaining the advantageous mechanical properties of the bulk polymer. We have explored the use of multi-end-functionalized polymer additives which undergo rapid adsorption to a surface or interface as an efficient method of modifying surface properties. Aryl ether moieties bearing up to four C8F17 groups have been used as initiators in the copper-mediated living radical polymerization of both styrene and methyl methacrylate, and the resulting polymers have been used as additives to render the surfaces of the corresponding bulk polymers hydrophobic and oleophobic. When such an additive consisting of a polystyrene chain with a molecular weight of ~10,000 g mol-1 end-capped with four C8F17 groups is present (in a matrix of polystyrene) at levels between 5 and 10 wt %, near PTFE-like surface properties result.