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In this paper, two phosphate functionalized acrylic binders are formulated to yield direct-to-metal paints without using corrosion inhibitors. The difference between both binders is the addition of polystearylacrylate crystalline nanodomains in one of them, and an amorphous methyl methacylate-co-butyl acrylate copolymer in the other. The water sensitivity, mechanical stability, adhesion, and the performance of the paints against corrosion (high humidity resistance, accelerated weathering, and salt-spray tests) are assessed and compared with a DTM paint formulated from a commercial binder. The performance of both phosphate functionalized paints formulated without corrosion inhibitors in high humidity and weathering tests is superior to the commercial DTM paint formulated without corrosion inhibitors and similar to the DTM paint formulated with them. Furthermore, the paint based on the amorphous copolymer binder provides significantly good performance in the salt spray test (even superior to that of the DTM paint formulated with corrosion inhibitors).

[EN] Four strategies to incorporate a fluorinated monomer (perfluoro octyl acrylate, POA) into a waterborne polymeric dispersion are investigated. Due to the very low water solubility of the POA monomer, three of the strategies use miniemulsion droplets containing the whole POA monomer in the initial charge. The rest of the comonomers of the formulation (methyl methacrylate, MMA, and n-butyl acrylate, BA) are partially incorporated in the initial miniemulsion or fed to the reactor as a preemulsion. In the fourth strategy, a conventional seeded semibatch emulsion polymerization is carried out using cyclodextrin in the seed and feeding the POA/MMA/BA preemulsion to the reactor. Each process strategy led to a distinct particle morphology and hence a particular film morphology. We found that the strategy that produced core-shell particles with the core composed by pure polyPOA yielded the films that showed the best corrosion protection as measured in salt-spray test (1200 h standing without damage).

286 p., The design of thin and multifunctional waterborne latexes for anticorrosion application has been carried out in this thesis. Poly(MMA-co-BA) waterborne latex (MB) with phosphated functionalities (provided by using a polymerizable phosphate surfactant) was synthetized in order to trigger the formation of a passive thin iron phosphate layer at the metal-coating surface during its application. In fact it was found that phosphate waterborne latex was able to phosphatize the steel surface when cast onto low carbon steel and dried under slow drying rate (T=23 °C and RH= 60%) leading to excellent anticorrosion protection in harsh conditions of salt spray chamber. In an attempt to increase the barrier properties of this initial waterborne phosphate containing latex, the incorporation of high hydrophobic perfluorooctyl acrylate (POA) into the polymer composition was targeted. However, despite the enhanced hydrophobicity and the presence of iron phosphate layer at the coating-substrate interface, the coating cast from PMB was not able to protect the metal substrate against corrosion in the harsh conditions present in the salt spray chamber. In order to overcome the poor anticorrosive performance of POA nanohybrid latexes containing ZnO nanoparticles and phosphate functionalities was prepared. Unfortunately, the encapsulation of ZnO nanoparticles produced just a slight enhancement of the corrosion protection and these results indicate that the incorporation of ZnO nanoparticles is not enough to overcome the problem of the lack of coalescence of polymer particles observed for film cast from PMB latexes. The incorporation of hydrophobic Stearyl Acrylate into the latex composition was implemented as alternative and the synergic effect of enhanced barrier properties and substrate phosphatization allowed an enhancement of the corrosion protection with respect to the initial system based on MB. Finally, the incorporation of phosphated waterborne latexes (MB, SA40 and SA50) into comm

In the present work a thin, stand-alone waterborne coating with excellent anticorrosion performance was successfully designed thanks to a built-in ability to in-situ phosphatize low carbon steel substrates. During film formation, the phosphate functionalities, incorporated by using a phosphate functional surfmer, were able to interact with steel leading to a thin iron phosphate passive layer at the coating-metal interface, as proven by SEM-EDX, FTIR and XPS. The phosphatization layer that plays a key role on the excellent anticorrosion properties obtained (measured by EIS analysis of coated sample immersed in 3.5 wt% NaCl solution and in an aggressive salt spray chamber), strongly depends on the humidity at which the waterborne dispersion is applied; at relative humidity above 60%, optimum performance is achieved.

MicroRNAs (miRNAs) are important regulators of biology and disease. Recent animal efficacy studies validate the therapeutic benefit of miRNA modulation and underscore the therapeutic value of miRNA-targeting oligonucleotides. However, whether disease conditions (stress) influence the pharmacological effects of an anti-miR is currently unknown. To study the effect of disease on target regulation after anti-miR treatment, we injected animals with anti-miR-208a, a synthetic oligonucleotide that inhibits the cardiomyocyte-specific miR-208a. Our data indicate that the presence of stress increases the number of regulated miR-208a targets, and that higher stress levels correlate with stronger target derepression. Additionally, the type of stress also influences which targets are regulated upon miR-208a inhibition. Studies in a large animal model indicate a similar stress-dependent anti-miR effect. Subsequent in vitro studies suggest that the influence of stress on anti-miR efficacy depends at least in part on increased cellular anti-miR uptake. These data indicate that the pharmacological effect of anti-miRs is stronger under disease conditions, and that both the type and severity of disease determine the therapeutic outcome. These facts will be important for assessing the therapeutic dose and predicting the therapeutic outcome when applying anti-miRs in a clinical setting.