In this work, a novel anti-smudge coating system was developed by using hydroxyl-terminated hyperbranched polyester as a coating precursor, mono-hydroxylterminated poly(dimethylsiloxane) (PDMS) as an antismudge agent, and hexamethylene diisocyanate trimer as a curing agent. The resultant coatings with 0.5 wt % PDMS content incorporated are highly transparent and liquid repellent. They exhibit striking repellency against various liquids and display remarkable self-cleaning performance. Water, hexadecane, salt solution, strong alkali solution, strong acid solution, pump oil, and crude oil could slide off the coated surface without leaving any traces, and the dirt on the coated surface could be readily removed by water or oil. Besides, these coatings show potential application for anti-fingerprint and anti-graffiti due to the exceptional repellency of coated surface against artificial fingerprint liquid, oil-based ink, paint, and water-based smudge. Furthermore, they also possess superb chemical shielding ability and thus endow substrates with remarkable protection against exposure to harsh chemical conditions. Moreover, these coatings are mechanically robust against extensive abrasion, impact, and bending without compromising antismudge properties, and they also exhibit excellent adhesion to various substrates. Therefore, these newly developed coatings have tremendous potential for widespread applications.

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Three kinds of nanoclays with different structure and morphology were modified by γ-amino­propyl­triethoxysilane (APTES) and then incorporated into Jatropha oil-based waterborne polyurethane (WPU) matrix via in situ polymerization. The effects of surface structure and morphology of nanoclay on the degree of silylation were characterized by Fourier transform infrared spectroscopy (FTIR) and thermogravimetry analysis (TGA). The results showed that the montmorillonite (MT) with abundant hydroxyl group structure and platelet-like morphology had the highest degree of silylation, while the modified halloysite nanotubes (HT) had the lowest grafting ratio. The effects of different silylated clays on the properties of WPU/clay nanocomposites were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), TGA, dynamic thermomechanical analysis (DMA) and tensile testing machine. SEM images showed that all silylated clays had good compatibility with WPU and were uniformly dispersed into the polymer matrix. WPU/SMT exhibited the best thermal properties owing to its intercalated structure. Dynamic thermomechanical analysis (DMA), atomic force microscope (AFM), and water contact angle results demonstrated that the silylated nanoclays enhanced the degree of microphase separation, surface roughness, and hydrophobicity of WPU/clay nanocomposites.