The majority of resins, adsorbents, ion-exchangers currently on the market are optimized for use in aqeuous matrices, ie water and water-rich solutions. However, no satisfactory resins are offered that retain their physical morphology in hydrophobic solvents. Conventional resins with their low cross-linkage suffer either collapse or non-compatibility in non-aqueous solutions.

Redstone has developed a set of highly rigid resins for use in non-aqueous solutions such as organic solvents, complex extracts, supercritical CO2, essential and natural oils and other hydrophobic matrices. These new resins are unique and offer performance and functionality in hydrophobic environments where conventional resins do not perform. The different resins offer a good variation of different surface chemistries and thus different selectivities.

Application areas

Polar RP resins are highly cross-linked and display a cooperation of hydrophobic and hydrophilic surface functional groups. Several different polar co-functionalities are available that allow for screening of selectivity and binding of the target compound. Both selective retention and fractionation can be envisaged.

Their mesoporous porosity is optimal for typical organic molecules and the resins predominantly exclude most larger molecules. Its unique polymeric structure allows effective binding of various types of molecules in different types of solutions. Unlike other conventional resins, they retain their accessible surface also in non-aqueous liquids such as supercritical carbon dioxide, organic solvents, or different types of oils (natural food oils, essential oils, etc) where conventional resins with their lower rigidity may collapse or fail to perform otherwise.

They can be used in batch and suspension mode, but also in flow-through mode in a column. The large particles are optimal for preparative applications and sediment quickly in suspensions.

Examples of potential application in oils / hydrophobic liquids:

• Removal of unwanted contaminants
• Retrieval of valuable compounds
• Fractionation of complex mixtures
• Solid Phase Extraction after Liquid-Liquid Extraction
• Work-up / Clean-up of organic synthetic reactions