Engineering the Surface Properties of Poly(dimethylsiloxane) Utilizing Aqueous RAFT Photografting of Acrylate/Methacrylate Monomers

Polymeric surface grafting offers a tunable way to control the interfacial interactions between a material's surface and its environment. The ability to tailor the surface properties of poly(dimethylsiloxane) elastomer (PDMSe) substrates with functional chemistry, wettability, and roughness can enhance the fields of biofouling, microfluidics, and medical implants. We developed a reversible addition–fragmentation chain transfer (RAFT) polymerization technique to synthesize a host of copolymers composed of acrylamide, acrylic acid, hydroxyethyl methacrylate, and (3-acrylamidopropyl)trimethylammonium chloride with targetable molecular weight from ∼5 to 80 kg/mol and low dispersity of Đ ≤ 1.13. This RAFT strategy was used in conjunction with photografting to chemically engineer the surface of PDMSe with hydrophilic, hydrophobic, and anionic groups. Varying grafting time and copolymer composition allowed for targetable molecular weight, chemical functionality, and water contact angles ranging from 112° to 14°. These new material surfaces will be evaluated for their antifouling and fouling release potential.