Inorganic-organic hybrid polymers

The sol-gel technique allows the wet-chemical synthesis of purely inorganic thin layers. Inorganic coatings e.g. made if silica (SiO2) or alumina (Al2O3) can be applied to different surfaces. By simultaneously using organically modified compounds in the synthesis of such materials hybrid materials can be prepared that, on a molecular level, consist of both inorganic as well as organic domains. The mentioned domains are covalently linked. The share of organic and inorganic can be varied – theoretically between 100% inorganic and 100% organic. In many cases characteristics of such hybrids combine as well properties know from organic polymers as properties known from inorganic materials. Hybrids can be flexible as organic polymers but nevertheless exhibit a hardness which is rather attributed to glass. Materials often show excellent transparency and durability and can be processed at temperatures far lower compared to the annealing temperatures needed for “conventional” inorganic materials.

Sol-gel technique allows preparation of hybrid polymers employing various precursors. Additionally the systems can e.g. also be modified with nanoparticles or nano-clays. Following this approach, materials with a variety of properties as well as combination of properties can be synthesised - many authors speak of the possibility to “tailor” properties.

Certain properties that can be achieved as e.g. water and oil repellence, antistatic properties, abrasion resistance, chemical resistance, antibacterial activity, UV-protection, UV-stabilisation, or magnetic properties are of interest not only for textile materials. Probably the most interesting aspect is that the approach promises that different materials properties can be combined.