Development of hydrophobic paper substrates using silane and sol–gel based processes and deriving the best coating technique using machine learning strategies

Abstract

Low energy surface coatings have found wide range of applications for generating hydrophobic and superhydrophobic surfaces. Most of the studies have been related to use of a single coating material over a single substrate or using a single technique. The degree of hydrophobicity is highly dependent on fabrication processes as well as materials being coated and as such warrants a high-level study using experimental optimization leading to the evaluation of the parametric behavior of coatings and their application techniques. Also, a single platform or system which can predict the required set of parameters for generating hydrophobic surface of required nature for given substrate is of requirement. This work applies the powerful machine learning algorithms (Levenberg Marquardt using Gauss Newton and Gradient methods) to evaluate the various processes affecting the anti-wetting behavior of coated printable paper substrates with the capability to predict the most optimized method of coating and materials that may lead to a desirable surface contact angle. The major application techniques used for this study pertain to dip coating, spray coating, spin coating and inkjet printing and silane and sol–gel base coating materials.

Disposable paper-based microfluidics for fertility testing

“… Requires multiple steps, uses hazardous organic solvents. ( Yang et al., 2017 ; Abe et al., 2010 ; Li et al., 2010 ; Wang et al., 2014 ; Manoharan et al., 2021 ; Henares et al., 2017 ) Inkjet Etching Modified inkjet printer, polystyrene, toluene. Requires only one device to be fabricated.…”

“…In this method, the printer can be damaged due to the use of hazardous organic solvents. However, other safe alternatives such as hydrophobic sol-gels, including methyl silsesquioxane ( Wang et al., 2014 ), tetraethyl-orthosilicate ( Manoharan et al., 2021 ), and UV-curable acrylate ink where the paper is cured with UV after patterning are available for use as ink ( Henares et al., 2017 ). In addition to the described methods which were additive, meaning that the hydrophobic walls are added to the hydrophilic paper, inkjet etching is another alternative option that operates in a subtractive way.…”