Synthesis and characterization of a novel fluorinated waterborne polyurethane

A series of fluorine-containing water-based polyurethane (FWPU) were synthesized by using fluoro alcohol-terminated isocyanate trimer (F-HDIT) prepared from 3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluoro-1-octanol (TFO) and hexamethylene diisocyanate trimer (HDIT). The structure of F-HDIT and the wetting and spreading ability, hydrophobic and solvent-resistance properties of FWPU were investigated in detail. The results indicated that with the increase of F-HDIT, the latex particle size, the water/solvent resistance and elongation at break of FWPU increased. More interestingly, the wetting and spreading ability on non-polar substrates was enhanced with the introduction of F-HDIT and the surface tension of FWPU film/latex was decreased by 69.5%/17.3%. Meanwhile, the water/methylene iodide contact angles were increased from 54.0°/34.1° to 121.8°/90.7° respectively, showing good hydrophobic and solvent-repellence characteristics.