Surface Modification of Hydrophobic Powder by Plasma-Initiated Graft Polymerization

Abstract

For the purpose of uniform modification of hydrophobic powder surface, plasma-initiated graft polymerization of water-soluble monomers on polystyrene powder was studied and the influences of the amount of the powder, monomer concentration, and plasma irradiation were investigated.
It was found that a proper combination of the monomer concentration, the amount of monomer aqueous solution, and the powder amount that showed suspension state before and after graft polymerization seemed to be favorable to attain uniform surface modification. The powder irradiated by argon plasma showed hydrophobic property, so that the aggregation of the powder remained after graft polymerization. On the other hand, water vapor plasma was effective to give a good affinity to the powder surface for monomer aqueous solution, so that graft polymerization occurred under good dispersion state. From the results of SEM observation, powder particles were completely and uniformly covered by the grafted polymer when HEMA was used as a monomer.