4. Conclusions
A
designing and screening strategy for novel bio-inspired zwitterionic
polymer for rapid underwater adhesion and long-term antifouling
stability was proposed. The polymer molecules are divided into three
parts to fulfill the different functions of the antifouling material and
connect the different modules. In the process of the design of
zwitterionic polymer, different head groups, tail chains, scaffolds, and
degrees of branching are considered and compared.
The
adsorption capacity, fouling resistance, adsorption configuration, and
surface properties of molecules on the hydroxylation silicon wafer are
compared through multi-scale molecular simulation. By continuously
screening different molecules of each module, Dopa, TREN, and PSBMA are
the optimal molecules for the head group, scaffold, and tail chain in
this system, respectively. All the calculation results are consistent
and prove that tri-Dopa-PSBMA may become a target molecule with
excellent properties.
In
addition, tri-Dopa-PSBMA and sin-Dopa-PSBMA were successfully
synthesized by an ATRP method to be used to compare the surface
adsorption properties. From XPS characterization, surface adsorption
kinetics of Dopa-PSBMA was monitored to show that tri-DOPA-PSBMA adheres
to the substrate much faster than sin-Dopa-PSBMA in aqueous solutions.
The facile dip-coating method under an ambient environment has important
practical significance. At the same time, the LSCM image of FITC-BSA
adhered substrates indicated that tri-Dopa-PSBMA has excellent
anti-protein adsorption ability and long-term stability on the silica
surface at 4 ºC and 37 ºC. More importantly, the adhesion time of the
tri-Dopa-PSBMA to the target substrate underwater by the solution
dip-coating method is less than ten minutes, and there are no relevant
reports of surface modification of the polymer within ten minutes.
Finally, tri-Dopa-PSBMA is applied to modify the commonly used
hydrophobic PVDF membrane. The tri-Dopa-PSBMA can be efficiently grafted
on the PVDF membrane surface to fabricate surfaces with good surface
antifouling and self-cleaning ability.
In
summary, all calculations and experimental characterizations corroborate
each other, indicating a successful combination of theory and experiment
for the rational design of antifouling material. The mode of theoretical
design and screen, experimental synthesis, and practical application
greatly enhance new functional materials’ design efficiency. Our general
molecular engineering strategy offers a rapid way to design and
synthesize functional polymers for specific environments.