Fluorine-free mixed amphiphilic polymers based on PDMS and PEG side chains for fouling release applications

Abstract

Fluorine-free mixed amphiphilic block copolymers with mixtures of short side groups of polydimethyl siloxane (PDMS) and polyethylene glycol (PEG) were synthesized and studied for their ability to influence the surface properties and control the adhesion of marine organisms to coated surfaces. The settlement (attachment) and strength of adhesion of two different marine algae, the green seaweed Ulva and the diatom Navicula, were evaluated against the surfaces. It is known that hydrophobic coatings based on polydimethyl siloxane elastomers (PDMSe) are prone to protein adsorption and accumulation of strongly adherent diatom slimes, in contrast to PEG-based hydrophilic surfaces that inhibit protein adsorption and moderate only weak adhesion of diatoms. By incorporating both PDMS and PEG side chains into the polymers, the effect of incorporating both polar and non-polar groups on fouling-release could be studied. The dry surfaces were characterized by X-ray photoelectron spectroscopy (XPS) and near-edge X-ray absorption fine structure spectroscopy (NEXAFS). The ability of these mixed amphiphilic polymers to reconstruct in water was examined using underwater bubble contact angle and dynamic water contact angle experiments. To understand more about surface reconstruction behavior, protein adsorption experiments were carried out with fluorescein isothiocyanate-labeled bovine serum albumin (BSA-FITC) on both dry and pre-soaked surfaces.

Amphiphilic Polymer Platforms: Surface Engineering of Films for Marine Antibiofouling

“…This amphiphilic and dynamic nature resulted in AF and FR attributes against the attachment of U. linza zoospores and the release of U. linza sporelings and N. perminuta cells. In particular, surfaces coated with copolymers richer in PEG or possessing longer PEG chains showed higher efficacy in reducing cell attachment as well as reducing adhesion strength.…”

“…Several fluorine‐free surface‐active copolymers were also prepared by attaching to a P(S‐ b ‐(E/B)‐ b ‐PI) triblock copolymer precursor separately PDMS and PEG pendant chains, non‐ionic amphiphiles, including hydrocarbon‐PEGylated Brij‐type side chains, and PEGylated‐hydrocarbon side chains ( 3 , Figure ). All the fluorine‐free SEBS‐based coatings derived therefrom shared the ability to become more hydrophilic after immersion in water, due to a reconstruction process which involved the migration to the surface of the hydrophilic PEG chains, while the non‐polar segments became buried in the bulk.…”

Laboratory culture and evaluation of the tubewormFicopomatus enigmaticusfor biofouling studies

“…The third test surface, PDMSe, was chosen because it is used frequently as a standard in foulingrelease assays (Sundaram et al 2011;Wang et al 2011). The PDMSe was the same as the unpigmented PDMSe used by Mieszkin et al (2012).…”

Amphiphilic pentablock copolymers and their blends with PDMS for antibiofouling coatings

“…Overall the results indicate a higher protein adsorption on all the surfaces of the PDMS‐matrix coatings with or without fluorinated pentablock copolymer. This is possibly due to favourable interactions of proteins with hydrophobic PDMS, which is prone to protein adhesion . The pentablock copolymer alone had consistently higher protein‐resistance properties than the PDMS coatings, but much lower than the diblock copolymers not containing the siloxane block.…”