Hybrid Organic/Inorganic Coatings Through Dual-Cure Processes: State of the Art and Perspectives

Abstract

This paper reviews the current state of the art related to the synthesis and characterization of hybrid organic-inorganic (O/I) coatings obtained through the exploitation of dual-cure processes, which involve a photo-induced polymerization followed by a thermal treatment: this latter allows the occurrence of sol-gel reactions of suitable alkoxy precursors already embedded in the UV-curable system. After a brief introduction on hybrid organic-inorganic coatings, the first part of the review is focused on the design and feasibility issues provided by the dual-cure method, emphasizing the possibility of tuning the structure of the final hybrid network on the basis of the composition of the starting liquid mixture. Then, some recent examples of hybrid organic-inorganic networks are thoroughly described, showing their potential advances and the application fields to which they can be addressed.

Surface-Engineered Fire Protective Coatings for Fabrics through Sol-Gel and Layer-by-Layer Methods: An Overview

“…Some examples considering the exploitability of dual-cure processes, i.e., a photo-induced polymerization followed by a thermal treatment for performing sol-gel processes, for the obtainment of hybrid organic-inorganic coatings on fabrics, are reported in the literature [36,37]. These hybrid coatings are able to behave as thermal insulators, inhibiting the fabric combustion and hence providing enhanced flame-retardant features.…”

“…These latter can be attained by combining the sol-gel coatings with other flame-retardant active species, such as phosphorus-and/or nitrogen-containing compounds, as will be discussed in the next paragraphs. Furthermore, the evolution of the sol-gel approach has led to the design of dual-cure processes, which can be utilized for obtaining hybrid organic-inorganic protective coatings [36], exploiting a photo-induced polymerization process followed by a thermal treatment for promoting the formation of sol-gel derived oxidic phases [37].…”

Sol-Gel and Layer-by-Layer Coatings for Flame-Retardant Cotton Fabrics: Recent Advances

“…As a consequence, the formation of a hybrid organic-inorganic coating is obtained on the cellulosic substrate. This coating usually exhibits flexibility and washing fastness according to the structure of the organic monomers/oligomers employed; besides, the in-situ formed ceramic phases are responsible for an increased thermal stability, as well as for the flame-retardant features provided to the cellulosic substrate [40][41][42], which are not significantly affected by the presence of the organic part of the designed coatings.…”

Insulating Thermal and Water-Resistant Hybrid Coating for Fabrics

“…Hybrid organic-inorganic compounds have the possibility to overcome these limitations joining thermal appealing properties of ceramics (inorganic phase) and of organic functional groups, providing a platform for a tailored functionalization of thermally active textile coatings [25][26][27][28]. It has been observed, in fact, that the continuous ceramic network of hybrid coatings, based on Si-O-Si linkages in the matrix, acts as a thermal insulator and mass transfer barrier for volatile compounds generated during thermal degradation [29][30][31][32][33][34][35][36][37][38], adding another reason for the interest in existing applications in optical, mechanical, biomedical, and electronic fields [2,[39][40][41][42].…”