| In this thesis, two kinds of polyurethane-acrylate coatings, waterbornepolyurethane-acrylate hybrid emulsionon and radiation curable polyurethane-acrylateoligomer, were prepared.Firstly, polyurethane prepolymer was obtained by using isophorone diisocyanate(IPDI),2,2-dimethylolpropionic acid (DMPA) or dimethylol butanoic acid(DMBA),poly(tetramethylene glycol)(PTMG) and polyether triol (MN-400) as raw materials.Polymethyl methacrylate emulsion and self-crosslinkable polymethyl methacrylateemulsion were synthesized by emulsion polymerization. Waterborne PU emulsion andwaterborne PA/PU hybrid emulsion were prepared by using water and self-madePMMA emulsion as dispersion medium. The effects of the molecular weight ofpolyether diols, types of hydrophilic chain-extending agent, content of MN-400andPMMA ratio on the properties of hybrid emulsions and films were investigated. Theoptimized formulation of waterborne PA/PU hybrid emulsion was obtained. Thehybrid emulsions and latex particles were characterized by FTIR, SEM.UV-curable PUA oligomer based on toluene diisocyanate(TDI), polypropyleneglycol of molecular weight1000(PPG1000),1,4-Cyclohexane dimethanol(CHDM)and2-hydroxyethyl methacrylate (HEMA) was prepared. The effect of content ofCHDM on properties of UV-cured PUA films was investigated. Radiation-curale PUAoligomers (γ radiation-curable and UV-curable) were synthesized with TDI, PPG1000,HEMA, pentaerythritol triacrylate (PETA) and trimethylolpropane trimethacrylate(TMPTMA). The structure of PUA was characterized by FT-IR. The influence of Rvalue, blocking agent (HEMA/PETA ratio) and radiation type on properties ofradiation-cured films were studied. The results showed that the PUA film cured by60γradition gave better comprehensive poperties than film cured by UV. The film curedby60γ radiation showed excellent flexibility, excellent wate-resistance andsolvent-resistance, strong adhesion, high hardness (the maximum pencil hardness of4H) and good thermal resistance. |
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