Fabrication of Hydrophobic and Breathable Protective Textiles based on Non-Fluorinated Organic and Inorganic Materials

Abstract

The demands for the functional textile having balanced and optimized properties is increasing by the day for their winning advantages like protection from severe environmental conditions in various technical applications. Protective textile refers to fabric-related items designed to protect the objectives environmental effects. However, their low wear resistance, complicated fabrication procedures, and high health risk limit their outdoor use. Based on the above considerations, we have studied the structure-dependent properties of organic and inorganic materials based protective textiles for wearable and functional applications. First, Waterproof breathable (WB) polyurethane (PU) porous membrane was fabricated for a membrane outside/fabric inside (MOFI) wearable fabric through an effective and facile dry process, called; Evaporation induced phase separation (EIPS). The matrix of the PU membrane was mainly modified by tiny water droplets and diisocyanate crosslinking agents, which allow the resultant membrane to be highly porous and durable. The WB porous membrane sustains a tensile load of 35 MPa with an abrasion resistance of 15,000 cycles, a high hydrostatic pressure of 3,500 mmH2O and good breathability of 3,000 g/m2day. These promising results show that WB membrane can compete with commercially available protective membranes and coating because of its porosity, facile synthesis, low cost, non-swelling behavior, high stability, and commercial-scale production. Second, this polymeric functional porous membrane was laminated to fabric to use in wearable textile applications. The lamination of the membrane to textiles without affecting its properties is a great challenge. Final membrane performance is dependent on fundamental parameters including membrane thickness, aging temperature, and adhesive aging temperature and time. This study aims to investigate the influence of these parameters on porous membrane morphology and performance. We analyzed membrane thickness impacts on morphology, pore size and physical performance such as water pressure, water vapor permeability, and resistance to evaporating heat transfer (RET). Kawabata evaluation system was used to evaluate the hand values based on quality according to customer choice. In optimized product, good mechanical, physical, and aesthetic performance of laminated textile suggest it as a promising substitute for numerous potential applications, especially as outdoor functional protective clothing. Non-wettable fabric surfaces fabricated with inorganic nanostructures having excellent mechanochemical robustness for practical applications have attracted much attention from researchers in recent years. However, such surfaces suffer from stability issues when exposed to harsh environments because of the weak bonding of the functional materials. Third, a unique facile approach is proposed to enhance the adhesion strength and hydrophobicity by improving the hierarchal roughness and opposite charge attraction using alkali and cationized bovine serum albumin (cBSA) respectively. Alkaline etching generated the microroughness and functional groups which facilitated the enhanced coupling of material on fiber surfaces. The etched fabrics were further treated with cBSA to introduce the positive charged functional groups which enabled the attachment of silica nanoparticles with the fiber surfaces through strong electrostatic attraction. Benefitting from this novel approach, the improved properties of the samples were confirmed through the water contact angle (WCA), self-cleaning effect, chemical/mechanical stability, and selective absorption of organic solvents. Forth, a robust super-hydrophobic surface was fabricated through the construction of a coral-reef like fibrous structure, followed by adhesive-assisted dip coating. Wrinkled fibrous nano-silica (WFNS) having a hierarchal surface and enhanced surface area was modified by silane agents and by coated on various substrates. This fibrous structure aids to minimize the water/solid interface resulted to achieve the super-hydrophobic surface with a water contact angle of 167°. To impart mechanical and chemical robustness, an adhesive-assisted approach was used. The combination of liquid repellency and exceptional robustness exhibited indicates the WFNS as a promising candidate for super-hydrophobic and self-cleaning applications. These novel organic and inorganic based functional textiles offer high functional performance and exceptional stability which make this promising substitute for numerous potential protective and other functional applications. These novel organic and inorganic based functional textiles offer high functional performance and exceptional stability which make this promising substitute for numerous potential applications.