Nonfluorinated Multifunctional Superhydrophobic Cellulose Sheet with Polysaccharide B Biopolymer-Based Hierarchical Rough Composite Structure

By virtue of the mixed-color effect between the oligochitosan (OCS)/aminopropyltriethoxysilane (APTES) aminated yellow pulp and reactive dyes, the 1,4-conjugate addition reaction of amino groups and acrylate groups was carried out onto the mixed-color amino-pulp surface to form a hierarchical rough polymeric structure; an oily pen writable polychrome cellulose sheet was fabricated via a squeezing–drying method and exhibited water-repellency, self-cleaning, antifouling, and good color stability. Based on the construction principle from cellulose pulp to the cellulose sheet, squeezing the hydrophilic colored cellulose filter cake covered on an undried superhydrophobic yellow cellulose sheet could form a Janus membrane with asymmetric wettability and color, which could be used for on-demand oil–water separation. Furthermore, after chitosan (CS) cooperating with APTES proceeded with the amination modification of cellulose pulp, the cellulose sheet with both superhydrophobicity and fluorescence produced from UV excitation was prepared via a biopolymer-based rough structure onto the aminated pulp caused by the above-mentioned 1,4-conjugate addition reaction and then the treatment of squeezing–drying. Meanwhile, this antiwetting cellulose sheet with UV photoluminescence exhibited a strong fluorescence intensity and outstanding resistance to fluorescence quenching, thus revealing good application prospects in durable fluorescence-labeled detection and fluorescent antifalse fiber. We believe that the as-prepared nonfluorinated multifunctional superhydrophobic cellulose sheet based on a simple room-temperature reaction and biomass materials, cellulose and polysaccharide biopolymer, as reaction units is conducive to the realization of cleaning production with a high-efficiency shortened process, which is promising in fundamental research and practical applications.