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Preparation of mechanically durable superwetting surfaces is imperative, yet challenging for the wide range of real applications where high durability is required. Mechanical wear on superwetting surfaces usually degrades weak roughness, leading to loss of functions. In this study, wear-resistant superhydrophilic/underwater superoleophobic and superhydrophobic surfaces are prepared by anchoring reinforced coatings via adhesive-swelling and adhesive-bonding processes, respectively. The results of the sandpaper abrasion (grit no. 600, 24 kPa) show that superhydrophilic nylon/SiO coatings and superhydrophobic polyurethane/TiO coatings retain their functions after suffering the abrasion distances of 70 cm and more than 1000 cm, respectively. Reinforced coatings formed by consecutive roughness and improved adhesion between coatings and substrates are responsible for repeatedly generated superwettability after exposure to mechanical stresses and demonstrated to be feasible for designing wear-resistant superwetting surfaces. Furthermore, this novel architecture of "reinforced coating with consecutive roughness + high adhesion" may demand desired coating materials and reliable coating-fixing techniques for sustaining sufficient roughness and is superior to currently existing technologies in advancing wear-resistance of superwetting surfaces.

Bagasse flour (BF) was liquefied using bi-component polyhydric alcohol (PA) as a solvent and phosphoric acid as a catalyst in a microwave reactor. The effect of BF to solvent ratio and reaction temperatures on the liquefaction extent and characteristics of liquefied products were evaluated. The results revealed that almost 75% of the raw bagasse was converted into liquid products within 9 min at 150 °C with a BF to solvent ratio of 1/4. The hydroxyl and acid values of the liquefied bagasse (LB) varied with the liquefied conditions. High reaction temperature combining with low BF to solvent ratio resulted in a low hydroxyl number for the LB. The molecular weight and polydispersity of the LB from reactions of 150 °C was lower compared to that from 125 °C. Rigid polyurethane (PU) foams were prepared from LB and methylene diphenyl diisocyanate (MDI), and the structural, mechanical and thermal properties of the PU foam were evaluated. The PU foams prepared using the LB from high reaction temperature showed better physical and mechanical performance in comparison to those from low reaction temperature. The amount of PA in the LB has the ability of increasing thermal stability of LB-PU foams. The results in this study may provide fundamental information on integrated utilizations of sugarcane bagasse via microwave liquefaction process.

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Visible light photoredox catalysis was combined with immersion particle lithography to prepare polynitrophenylene organic films on Au(111) surfaces, forming a periodic arrangement of nanopores. Surfaces masked with mesospheres were immersed in solutions of p-nitrobenzenediazonium tetrafluoroborate and irradiated with blue LEDs in the presence of the photoredox catalyst Ru(bpy)3(PF6)2 to produce p-nitrophenyl radicals that graft onto gold substrates. Surface masks of silica mesospheres were used to protect small, discrete regions of the Au(111) surface from grafting. Nanopores were formed where the silica mesospheres touched the surface; the mask effectively protected nanoscopic local areas from the photocatalysis grafting reaction. Further reaction of the grafted arenes with aryl radicals resulted in polymerization to form polynitrophenylene structures with thicknesses that were dependent on both the initial concentration of diazonium salt and the duration of irradiation. Photoredox catalysis with visible light provides mild, user-friendly conditions for the reproducible generation of multilayers with thicknesses ranging from 2 to 100 nm. Images acquired with atomic force microscopy (AFM) disclose the film morphology and periodicity of the polymer nanostructures. The exposed sites of the nanopores provide a baseline to enable local measurements of film thickness with AFM. The resulting films of polynitrophenylene punctuated with nanopores provide a robust foundation for further chemical steps. Spatially selective binding of mercaptoundecanoic acid to exposed sites of Au(111) was demonstrated, producing a periodic arrangement of thiol-based nanopatterns within a matrix of polynitrophenylene.