Preparation and properties of waterborne polyurethane with star-shaped hyperbranched structure

The second-generation hydroxyl-terminated hyperbranched polyester (HB-20) was used as the core, and perfluorooctylethanol (PFOE), monohydroxypolyoxyethylene ether (MPEG) and n-octadecyl alcohol (C18) were grafted to the periphery of HB-20, coupled by isophorone diisocyanate (IPDI) to synthesize four star hyperbranched polymers (SHPs). The structures of the four synthesized typical SHPs were characterized by FT-IR, 1H NMR and 19F NMR. The SHPs obtained were introduced into anionic waterborne polyurethane (WPU) and waterborne polyurethanes (FWPUs) with good storage stability modified by SHPs were prepared. The particle size and morphology of FWPUs were characterized by dynamic laser light scattering and TEM. The surface chemical composition and surface hydrophilic and hydrophobic regions of FWPU film were characterized by XPS and AFM. The surface energy, mechanical properties and thermal properties of FWPU film were determined. The water absorption and moisture permeability of FWPU film were also discussed.