Comb-like poly(dodecyl methacrylate) modified SiO2 nanoparticles as nanohybrid coatings: Electron beam grafting and tuning superhydrophobic/water-repellent surface studies

The current research focuses on tailoring silica nanoparticles (SiO2NPs) with comb-like poly(dodecyl methacrylate) (PDMA) brushes and tuning coating parameters based on roller coating process for confining surface morphology towards hydrophobic and superhydrophobic including water-repellent surface. Electron beam (EB) induced a simultaneous "graft-from" polymerization of DMA monomer onto vinyl modified SiO2NPs (SiO2NPs-V) was established in an inventive castor oil/ethanol mixed solvent. Functional surface chemistry of SiO2NPs and nanorough surface topography controlled by NPs content and coating thickness mainly influences the hydrophobic/superhydrophobic, water-repellent, and water absorption properties including gloss values, whiteness and yellowness index of coated papers. The papers coated with SiO2NPs-V-PDMA/PVA of 6–10 wt% with the thickness of ~10–14 μm exhibited matt surface and provided superhydrophobic and water-repellent properties. The coated paper has a desirable and stable water contact angle of 152°, low droplet adhesion with lower dynamic tilting angle (<5°), and 5.3-folds reduced water absorption. Our investigation provides compelling evidence that the SiO2NPs-V-PDMA obtained from EB modification and the developed coating formula for roller-based coating process are realistic approaches for hydrophobic/superhydrophobic coatings and printing inks for paper-based industries.