Surface Modification of Poly(ether urethane) by Chemical Infusion and Graft Polymerization

Abstract

The surface of a commercially available poly(ether urethane), Tecoflex^R, has been modified by either chemical infusion or graft polymerization techniques. The chemical infusion technique involves the physical entrapment of polymer additives in the near surface region of the sample, while graft polymerization provides chemical attachment of a polymer to the surface of the sample. The additives investigated for chemical infusion include poly(vinylpyrrolidone) (PVP) and poly(ethylene glycol) (PEG) along with iodine and silver nitrate as antibacterial agents. Graft polymerization covalently bonds polymers to the surface of the poly(ether urethane). The polymerization is initiated by photolysis of Re₂(CO)₁₀ to generate radicals on the poly(ether urethane) surface. The monomers examined for graft polymerization include N-vinyl pyrrolidone (NVP) and 2-hydroxyethylmethacrylate (HEMA), along with sulfonate containing monomers such as sodium vinylsulfonate, 2-acrylamido-2-methyl-1-propane sulfonic acid (AMPS) and its sodium salt (NaAMPS). The surface energies of these surface modified poly(ether urethane) samples were examined by contact angle measurements in water using the Wilhelmy balance technique. An increase in surface energy was observed following surface modification by both techniques, resulting in more hydrophilic surfaces than the untreated samples.