Comparative analysis of two isocyanate-free urethane-based gels for antifouling applications

Abstract

Amphiphilic gels consisting of acrylamide (AAM)/2-hydroxyethyl methacrylate (HEMA), hexafluorobutyl methacrylate (HFBMA) and non-isocyanate urethane dimethacrylate (NIUDMA) of varying molecular weights were compared. A three-level Taguchi analysis was performed using the amount of AAM/HEMA, HFBMA, NIUDMA and reaction time as dependent variables to determine the optimal formulation of the gels with maximized toughness and elastic modulus. The results were compared with commercial AF/FR Intersleek® coatings (IS 700, IS 900 and IS 1100SR) for their antifouling performance against a marine microalga (Navicula incerta), a marine bacterium (Cellulophaga lytica) and adult barnacles (Amphibalanus amphitrite). The toughness, elastic modulus and strain at break of the optimized AAM gels ranged from 3 to7 MPa, 25 to 72 MPa and 80% to 170%, respectively, whereas those of the optimized HEMA gels ranged from 1 to 3 MPa, 13 to 23 MPa and 76% to 160%, respectively. The gels, particularly AHN(E9) and HHN(E12), showed reductions of attachment compared with IS700 of up to 93% and 58%, respectively.

Graphical Abstract

Keywords:

• Antifouling
• amphiphilic
• Taguchi
• non-isocyanate
• gels

Acknowledgements

The authors thank Daniel Rittschof and Beatriz Orihuela at the Duke University Marine Laboratory for providing adult barnacles for the reattachment studies. This work was written and researched with the tools available in Dr. Anthony Brennan’s lab at the University of Florida Materials Science and Engineering Department.

Disclosure statement

There are no conflicts of interest to declare.

Additional information

Funding

The authors of this article would like to acknowledge the Office of Naval Research for funding this effort (N00014-16-1-3120 and N00014-17-1-2153).