Preparation of High Strength Zwitterionic Polymer Hydrogel Antifouling and Drag Reducing Coating

Polymethacrylate sulfonate Betaine (PSBMA) is a classic zwitterionic polymer. As a typical hydrogel, it has the characteristics of high water content, super hydrophilicity, low friction coefficient, low biological toxicity but poor mechanical properties. In this work, the natural and easily available kappa-carrageenan (kappa-CG) is employed to endow the preducor solution with good thixotropy. Then, the preducor solution is coated on the glass surface to form multicomponent double network hydrogel coating. In which, kappa-CG network is the first network, acrylamide (AM) and dimethylpropyl sulfonate ethyl methacrylate (SBMA) are the second network monomers, and N, N'-Methylene-bis(acrylamide) (MBAA) as crosslinkage agent. The kappa-CG network is further enhanced using zirconium ion (Zr4+) coordination crosslinking. Finally, we get the strong, tough and stable kappa-CG/AM/ SBMA multicomponent double network hydrogel coating. Benefitted by the double network structure, the mechanical properties of the zwitterion polyelectrolyte hydrogel are significantly strengthened. Its best fracture stress, fracture strain, and Young's modulus reaches 2.51 MPa, 1620.76% and 1.67 MPa, respectively, which basically meets the conditions for its use in the marine environment. The hydrogel coating swells weakly in different medium (water and seawater). Silane coupling agent KH-570 is used to modify the glass surface which help the hydrogel bond to glass surface. The adhesion energy of the hydrogel coating on glass surface obtained from the 90 degrees peel test reaches about 2500 J center dot m(-2). A series of experiments have shown that this kappa-CG/AM/SBMA ternary double network hydrogel has excellent hydrophilicity, high breaking strength, good toughness, high modulus and low swelling degree. At the same time, due to the existence of surface hydration layer, the hydrogel coating also behaves drag reduction and excellent performance in antifouling.