Abstract:
Microorganisms attachment to the surfaces located in the marine water has
become a significant problem. Historically, the antifouling properties of the
coatings were achieved by using biocides, which had a negative consequence
to the marine environment. Currently, alternative environmental friendly
methods are required. This thesis aimed to investigate and produce the
antifouling coatings that can be used as potential candidates in the marine
industry. In this study, a range of novel polymer nanocomposite coatings was
fabricated via the method of solvent and tested based on the strategy of
microbial adhesion. The composition of the coatings mainly contains
polidimethylsiloxane (PDMS) and different nanomaterials. The coatings applied
on glass substrate were characterised using X-ray spectroscopy (XRD),
scanning electron microscopy (SEM), contact angle measurements, inductively
coupled plasma mass spectroscopy (ICP-MS) and atomic force microscopy
(AFM).
In biofouling assays, attachment of bacteria B. Subtilis and three marine
microalgae (Skeletonema sp., Amphora sp., D. Salina) was investigated in
laboratory scale. The obtained results suggested that small amount of
nanoparticles in the polymer matrix can improve the antifouling settlement
behaviour of the coatings. All microalgae attached more on PDMS/SiO2 and
control surfaces (glass and PDMS) compared to the coatings containing
multiwall carbon nanotubes (MWCNT) and sodium bismuth titanate (NBT).
The influence of contact time, surface roughness and surface wettability was
also studied. The microbial attachment varied significantly with respect to
contact time and surface properties. There was no obvious evidence showing
that the wetting properties and the roughness of the coatings have an effect on
growth ... [cont.].