Fabrication of polybutadiene modified waterborne polyurethane coatings with excellent anti-smudge characteristics

Low cost and environmental friendly anti-smudge coatings are highly desirable because of their repel ability to numerous contaminants. Herein, a fluorine-free and transparent anti-smudge waterborne polyurethane coating (WPUH) was constructed via the copolymerization of hydroxyl-terminated polybutadienes (HTPB) into polyurethane backbones. The effect of HTPB content on the particle size and storage stability of the synthesized WPUH emulsions was studied using dynamic light scattering (DLS). The micro- and nano-structures of the resulting coatings were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). Furthermore, the surface of the resulted WPUH coatings showed excellent anti-smudge performance toward various liquids, such as water, ethanol, and mark pen oil, etc. In particular, the WPUH20 coating (with 20 wt% of HTPB) exhibited a water contact angle of 72 ± 3 ° and maintained its anti-smudge performance even after 100 abrasion cycles. This work provides an attractive strategy for preparation of cost-effective and environmental friendly WPU anti-smudge coatings, which is promising for widespread applications.