| A series of water-based polyurethane resin with high corrosion resistance were synthesized and characterized in this work. They can be used as protective coatings of aircraft cabin under marine climatic conditions. The overall performance of emulsion and coating was tested and investigated.Polyurethane modified by silicone (SiPU) emulsion and coating were successfully synthesized by using hydroxypropyl-terminated polydimethylsiloxane (PDMS), polyethylene glycol (PEG), dimethylolpropionic acid (DMPA) and diphenyl methane diisocyanate (MDI). The structure of SiPU was confirmed by FT-IR. It was in line with the theoretical design. The effects of PDMS content, DMPA content and R value on emulsion and coating were investigated. The optimum formula was achieved when R value was 0.9, PDMS content was 12% and DMPA content was 6%.On the basis of SiPU, a new material hydroxyl acrylic resin and acrylate monomers were introduced into the system to obtain silicone-containing polyurethane acrylate aqueous dispersion (SiPUA/PA). TEM results showed that the particle morphology of SiPUA/PMMA was regularly spherical and PMMA domained in the core region. FT-IR and DSC confirmed the presence of PMMA. The reinforcement of PMMA rigid particles in silicone-containing polyurethane-acrylic ternary copolymer were confirmed by measuring the dynamic rheological properties. The hydrophobicity is highly dependent on PDMS contents. The optimum formula was achieved when PDMS content was 10% and PMMA/SiPUA value was 0.5. Different acrylate monomers MMA, MMA and BA compounds, MMA, BA and EA compounds was introduced into the SiPUA composites. Those coatings were smooth and transparent. The coating could achieve high hydrophobicity when MMA, BA and EA were introduced into the system.A series of waterborne polyurthe modified by epoxy and acrylic resin (EPUA) was prepared. The effects of epoxy content, DMPA content, different epoxy resins, hydrophilic group, neutralization, solid content and coating process on EPUA emulsions and coatings wree investigated. FT-IR confirmed the structure and the reaction during the curing process. Particle size of EPUA emulsion showed a single peak distribution. The average particle diameter was 86nm. EPUA emulsions had the excellent dispersibility. The coating showed poor corrosion resistance when epoxy resin content was too low. The emulsion showed poor thermal stability when epoxy resin content was more than 12%. The The optimum formula was achieved when epoxy resin content was 10%, DMPA content was 9%, epoxy resin was E44, BPA was the chain extender, neutralization was 100% and solid content was 35%. Compared to the method that DMPA was directly added into the system for solid phase reaction, it carried out homogeneous reactions in the way that the hydrophilic groups were salt-forming first. The salt-forming method showed higher degree of reaction, pencil hardness and thermal stability. Swelling ratio increased with the increase of the heating time, when the heating temperature was constant. Swelling ratio increased with the increase of the heating temperature, when the heating time was constant. |
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