Transparent omniphobic polyurethane coatings containing partially acetylated β–cyclodextrin as the polyol

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Vol. 380; p. 122554
• Main Authors: Lei, Lei, Buddingh, Jasmine, Wang, Jiandong, Liu, Guojun
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.01.2020
• Subjects: Anti-smudge coatings; NP-GLIDE coatings; Polyurethane; β-cyclodextrin; NP-GLIDE coatings; Anti-smudge coatings; β-cyclodextrin; Polyurethane
• ISSN: 1385-8947; 1873-3212
• DOI: 10.1016/j.cej.2019.122554

[Display omitted] •Bio-renewable β-cyclodextrin is used as the polyol for an anti-smudge polyurethane coating.•The in-situ polyol-g-PDMS production simplifies coating preparation.•This coating is greener than the traditional anti-smudge coatings.•The transparent and wear-resistant coating repels liquids and contracts inks and paint. Polyurethane is currently prepared from a polyisocyanate and a polyol derived from depletable and non-sustainable petroleum precursors. This paper reports the partial acetylation of β-cyclodextrin (CD), derived from the renewable starch by enzymatic conversion, and the subsequent use of the acetylated CD as the polyol to produce a greener polyurethane. More importantly, a method for incorporating the low-surface-tension liquid poly(dimethyl siloxane), PDMS, into the new polyurethane formulation is reported. The final polyurethane coating bearing a liquid-like PDMS monolayer on its surface and nanometer-sized PDMS pools in its matrix is transparent and exhibits superior oil and water repellency. On the coating, various test liquids with surface tensions above ~22 mN/m cleanly glide at low substrate tilt angles and complex fluids such as ink and paint samples readily contract. While the green polyurethane coating and its omniphobic or anti-smudge counterpart are promising candidates for practical applications, the approaches used in this study should be adaptable for modifying other biomass-based precursors such as sugars or even possibly starch for preparing green polyurethanes and omniphobic polyureathanes.