Structure-Property Relationships of Silicone Biofouling-Release Coatings: Effect of Silicone Network Architecture on Pseudobarnacle Attachment Strengths

Abstract

Model silicone foul-release coatings with controlled molecular architecture were evaluated to determine the effect of compositional variables such as filler loading and crosslink density on pseudobarnacle attachment strength. Pseudobarnacle adhesion values correlated with filler loadings in both condensation and hydrosilylation-cured silicones. Variation of crosslink density of hydrosilylationcured silicones had an insignificant effect on attachment strength. X-ray photoelectron spectroscopy (XPS) indicated that the mode of failure upon detachment of the pseudobarnacle was dependent upon the crosslink density; samples with high crosslink density failed cohesively within the silicone.

Whole cell adhesion strength of morphotypes and isolates of Phaeodactylum tricornutum (Bacillariophyceae)

“…The basis of this preference is not known but it provides an interesting contrast with the adhesion characteristics of other fouling organisms such as barnacles and seaweeds that adhere more strongly to hydrophilic surfaces and weakly to hydrophobic silicones (e.g. Swain, 1999;Kavanagh et al, 2001;Stein et al, 2003;Finlay et al, 2005;Sun et al, 2005). The availability of a good model system in P. tricornutum, with publication of its complete genome sequence, and the development of microarrays (Scala et al, 2002;Montsant et al, 2005), now facilitates the analysis of surface preferences for adhesion through molecular genetic and gene expression studies.…”

Fouling release nanostructured coatings based on PDMS-polyurea segmented copolymers

“…On the other hand, neat silicones display exceptionally poor mechanical properties (raising concerns about their long term durability), and are therefore typically reinforced with large quantities of inorganic particles or by chemical cross-linking. However, such strategies have detrimental effects on toughness, processability, and chain mobility, which, in turn, adversely affect fouling release behavior [13,14].…”

Temperature Affects Adhesion of the Acorn Barnacle (Balanus amphitrite)

“…Silastic, produced by Dow Corning, has been used in studies (Stein et al 2003;Sun et al 2004;Kavanagh et al 2005;Holm et al 2006) as a good model system for the study of foul-release properties against marine organisms. Its chemical properties and structure is well known, it does not leach any toxins, and it is fairly inexpensive.…”

“…When the plaque was analyzed with atomic force microscopy (AFM), the image showed that the layer closest to the basal plate was a closely packed granular structure compared to the continuous film-like appearance of the rubbery cement removed from poly(methylmethacrylate) (PMMA). PDMS technology is promising in that it has been proven to significantly reduce barnacle attachment to hard substrata (>1.0 x 10 6 N/m 2 ) to levels that enable easy removal (1.0 x 10 5 N/m 2 ) (e.g., Kavanagh et al 2001;Stein et al 2003;Kavanagh et al 2005)). (Watermann et al 1997) Figure 5.…”