Antifouling activity of novel polyisoprene-based coatings made from photocurable natural rubber derived oligomers

摘要

Natural rubber is a renewable resource with a potential as precursor of a very wide range of novelpolymers, including polyisoprene-based surfaces with antifouling (AF) activity. In this work, new ionicand non-ionic coatings were prepared by the photocrosslinking reaction of photosensitive cis-1,4-oligoisoprenes, bearing a variable number of ammonium groups. The photochemical crosslinking wasachieved using radical (via acrylate groups) or cationic (via epoxy groups) processes. Surface propertiesof these coatings were studied by static contact angle measurements and AFM imaging. Assessment ofbioactivity demonstrated that most of the resulting coatings showed AF potential against fouling organisms:growth inhibition of marine bacteria (Pseudoalteromonas elyakovii, Shewanella putrefaciens, Cobetiamarina, Polaribacter irgensii, Vibrio aestuarianus) and fungi (Halosphaeriopsis mediosetigera, Asteromycescruciatus, Lulworthia uniseptata, Zalerion sp., Monodictys pelagica); decreased adhesion of microalgae(Navicula jeffreyi, Cylindrotheca closterium, Chlorarachnion globosum, Pleurochrysis roscoffensis, Exanthemachrysisgayraliae, Amphora coffeaeformis); inhibition of attachment and/or germination of sporesof Ulva intestinalis. The best AF activity was obtained with the ionic surfaces. These new coatings preparedfrom precursors obtained from natural rubber are in essence active by contact. As the biocidalfunctions are fixed covalently to the polymer chain, detectable release of biocidal products in the marineecosystem is prevented so that a valuable environment-friendly alternative for new AF coatings is herebyproposed.