Preparation of an environmentally friendly antifouling degradable polyurethane coating material based on medium-length fluorinated diols

Synthesis, Structure, Properties, and Applications of Fluorinated Polyurethane

Fluorinated polyurethane (FPU) is a new kind of polyurethane (PU) material with great applicational potential, which is attributed to its high bond energy C-F bonds. Its unique low surface energy, excellent thermal stability, and chemical stability have attracted considerable research attention. FPU with targeted performance can be precisely synthesized through designing fluorochemicals as hard segments, soft segments, or additives and changes to the production process to satisfy the needs of coatings, clothing textiles, and the aerospace and biomedical industries for materials that are hydrophobic and that are resistant to weathering, heat, and flames and that have good biocompatibility. Here, the synthesis, structure, properties, and applications of FPU are comprehensively reviewed. The aims of this research are to shed light on the design scheme, synthesis method, structure, and properties of FPU synthesized from different kinds of fluorochemicals and their applications in different fields and the prospects for the future development of FPU.

Improving environmental protection of waterborne polyurethane coating by adding TiO2/polyaniline/HNT/CNT nanocomposite

Nanostructures of titanium dioxide, polyaniline, halloysite, and carbon nanotubes have an excellent effect to improve environmental protection and surface properties of coatings like anticorrosion and self-cleaning attributes. In this research, we studied the individual effect of adding each nanostructure within the polyurethane matrix and also all nanostructure combinations with each other on the mentioned properties. To reach this aim, the polyurethane nanocomposites were prepared; then, anticorrosion and self-cleaning tests were carried out on the samples. FTIR spectroscopy and FESEM images were used to characterize the nanocomposite additives and coating influence. According to the obtained results, the polyurethane coating modified with titanium dioxide/polyaniline/halloysite nanotube/carbon nanotube nanocomposite showed very higher corrosion potential and resistance and lower corrosion current in the comparison with other coatings. Also, the mentioned polyurethane nanocomposite coating showed good hydrophilicity and it decolorized a dye contaminant with high efficiency which makes them appropriate candidate for the protection of the substrate against environmental destructive factors.

A New Strategy for the Synthesis of Fluorinated Polyurethane

An alternating fluorinated copolymer based on chlorotrifluoroethylene (CTFE) and butyl vinyl ether (BVE) was synthesized by RAFT/MADIX living/controlled polymerization in the presence of S-benzyl O-ethyl dithiocarbonate (BEDTC). Then, using the obtained poly(CTFE-alt-BVE) as a macro chain transfer agent (macro-CTA), a block copolymer was prepared by chain extension polymerization of vinyl acetate (VAc). After a basic methanolysis process, the poly(vinyl acetate) (PVAc) block was transferred into poly(vinyl alcohol) (PVA). Finally, a novel fluorinated polyurethane with good surface properties due to the mobility of the flexible fluorinated polymer chains linked to the network was obtained via reaction of the copolymer bearing the blocks of PVA with isophorone diisocyanate (IPDI) as a cross-linking agent.