Some factors governing the coating of organic polymers by sol-gel derived hybrid materials

Organic-inorganic hybrid materials can exhibit some properties of organic polymers, such as toughness and elasticity, and/or that of ceramics, such as chemical stability and hardness. In this review, we discuss the main factors that should be considered when coating a polymeric substrate with a sol-gel derived organic-inorganic hybrid material. The effects of the solution characteristics, the polymer substrate chemistry and preparation, the application process and materials characteristics are considered. Examples of commercial and published systems are discussed. We find that due to the wide diversity of the systems investigated, it is difficult to be specific in recommending guidelines applicable to all systems. However, some general considerations can be made that should be useful in the design of functional hybrid coatings aimed at improving the characteristics of polymeric surfaces.