Textile functionalization by combination of twin polymerization and polyalkoxysiloxane‐based sol–gel chemistry

Abstract

The surface modification of textile fibers by coating with nanostructured organic–inorganic hybrid materials is presented. The hydrophobic, solvent resistant and mechanically robust coatings were produced by combining the twin monomer 2,2′‐spirobi[benzo‐4H‐1,3,2‐dioxasiline] (TM) and polyalkoxysiloxanes (silica precursor polymers) in a catalyzed polymerization process. For the application in textile finishing, both aqueous emulsions and ethanolic solutions of mixtures were developed. The precisely adjusted ratio of TM and polyalkoxysiloxanes enabled controlling of the organic and inorganic portions in the hybrid layer. The polymerization process can be advantageously combined with the ring‐opening polymerization of hexamethylcyclotrisiloxane (HMCTS). The resulting ethanolic twin prepolymer solutions and the polyethoxysiloxane emulsions were easy to handle and thus represent a novel and attractive binder for PET surfaces. The coated fabrics were analyzed by means of scanning electron microscopy and X‐ray photoelectron spectroscopy showing hybrid material formation as a homogeneous, sealed surface layer. Improved hydrophobicity as well as resistance to mechanical stress was proven by water droplet‐ and Martindale tests.

Twin Polymerization: A Unique Strategy towards Versatile Functional Materials

“…[87] SEM studies (Figure 1) confirmed that 10 containing polymers seem to raise a higher adhesion towards the reinforcement fibers involving an enhanced fiber/matrix interaction. [87] Recently, also textile functionalization by the combination of TP with 1 and polyalkoxysiloxane-based sol-gel chemistry to achieve improved adhesion and permanence and hydrophobicity was published by Kaßner et al [88] When 1 was polymerized Scheme 4. Procedure for the preparation of urethane-based twin prepolymers 8 a,b (top) and their STP with 1 to obtain hybrid materials consisting of phenolic resin, silica and dialkylsiloxane-crosslinked polyurethane (PPG = polypropylene glycol, PTMEG = polytetramethylene ether glycol, MDI = methylendi(phenylisocyanate)) (middle).…”

“…[88] Abrasion testing on polyester fabrics were carried out. [88] Furthermore, the authors state that the corresponding organic-inorganic hybrid coatings may open up new perspectives for the finishing of diverse textile materials and can be combined modularly with other chemically reactive reagents, for example, UV resistant additives, amino and epoxy groups to admix and fix nanoparticles, or dyestuffs. [88] Based on earlier studies on TP on hard templates, [18] Spange and coworkers used in 2017 TP for the fabrication of hierarchically structured carbon/carbon nanocomposites with adjustable porosity by applying consecutive surface polymerization of twin monomers on carbon black and silica particles, respectively.…”

“…[88] Furthermore, the authors state that the corresponding organic-inorganic hybrid coatings may open up new perspectives for the finishing of diverse textile materials and can be combined modularly with other chemically reactive reagents, for example, UV resistant additives, amino and epoxy groups to admix and fix nanoparticles, or dyestuffs. [88] Based on earlier studies on TP on hard templates, [18] Spange and coworkers used in 2017 TP for the fabrication of hierarchically structured carbon/carbon nanocomposites with adjustable porosity by applying consecutive surface polymerization of twin monomers on carbon black and silica particles, respectively. [89] As twin monomers they used 1 and tetrafurfuryloxysilane (14), which have been polymerized in a single step to produce an organic-inorganic hybrid material, containing nanostructured silica and phenolic resin or poly(furfuryl alcohol) as organic polymer, which after carbonization and SiO 2 removal produced a porous carbon shell with well-defined porosity (Scheme 6, top).…”

“…Postulated structure formation during the TP process of 1 in presence of variable amounts of polyethoxysiloxane (followed by hydrolysis) and hexamethylcyclotrisiloxane. [88] shell and double-shelled carbon hollow spheres. The use of these materials as host for sulfur in lithium-sulfur batteries was envisaged (see below).…”

“…[89] For NPloaded materials NPs can be easily integrated either directly from the twin monomer or using TP in presence of metal carboxylates. [73] Moreover, TP is not just a competing methodology to the sol-gel process [8,88,112] but can also be integrated into it, which opens an extensive field of research for future studies.…”