Preparation of Water-Resistant Antifog Hard Coatings on Plastic Substrate

Abstract

A novel water resistant antifog (AF) coating for plastic substrates was developed, which has a special hydrophilic/hydrophobic bilayer structure. The bottom layer, acting both as a mechanical support and a hydrophobic barrier against water penetration, is an organic-inorganic composite comprising colloidal silica embedded in a cross-linked network of dipentaethritol hexaacrylate (DPHA). Atop this layer, an AF coating is applied, which incorporates a superhydrophilic species synthesized from Tween-20 (surfactant), isophorone diisocyanate (coupling agent), and 2-hydroxyethyl methacrylate (monomer). Various methods, e.g., FTIR, SEM, AFM, contact angle, and steam test, were employed to characterize the prepared AF coatings. The results indicated that the size and the continuity of the hydrophilic domains on the top surface increased with increasing added amount of T20, however, at the expense of hardness, adhesiveness, and water resistivity. The optimal T20 content was found to be 10 wt %, at which capacity the resultant AF coating was transparent and wearable (5H, hardness) and could be soaked in water for 7 days at 25 °C without downgrading of its AF capability.

Zwitterionic polymer brush coatings with excellent anti-fog and anti-frost properties

“…[1][2][3][4] Over the last few decades, an extensive research studies have been reported to prevent the formation of fog and frost on solid surfaces by different approaches including superhydrophobic coatings, 5-7 superhydrophilic coatings 8,9 and combinations of both hydrophilic and hydrophobic properties in the coating. [10][11][12][13][14][15] Hydrophilic surfaces that have a water contact angle of less than 5 o exhibit excellent anti-fog properties because they allow water droplets to spread uniformly to form a thin water film, which reduces light scattering. 9,16,17 In general, superhydrophilicity can be obtained by various chemical and physical methods.…”

Preparation of superhydrophilic nanosilica/polyacrylate hard coatings on plastic substrate for antifogging and frost‐resistant applications

“…25 for details. The water contact angle of the AFF surface was measured by a contact angle/surface tension analyzer (FTA 125, First Ten Angstroms) at 25 C. A 6 μL drop of water deposited on the sample surface was imaged and shape-analyzed to obtain the contact angle.…”

“…Fogging/frosting occurs frequently in our daily life. 1,2,[19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34] There is great demand for effective AFF surfaces to maintain visibility and transparency in relatively moist environments. To avoid its formation, it is useful to apply an antifog/frost resistant (termed AFF, hereinafter) layer on the surface of use, particularly when the surface is hydrophobic and susceptible to deposition of moisture droplets.…”

“…25 The bottom layer, serving as a binder, mechanical support, and water-resisting barrier, was an inorganic-organic composite of silica and crosslinked polyacrylate. Previously, we have demonstrated the preparation of a water-resistant antifogging coating with a bilayer configuration.…”

Red photoluminescent PMMA nanohybrid films for modifying the spectral distribution of solar radiation inside greenhouses

“…These nanohybrids will generally provide more diffuse light than traditional fluorescent PMMA films due to its translucent nature. In addition, the use of nanotechnology in polymer science have introduced several advantages in different areas such as flammability resistance, optical properties, weathering stability, mechanical strength and antifogging effect [18].…”