SUPERCRITICAL-FLUID CHROMATOGRAPHY AND EXTRACTION IN SURFACE-COATINGS ANALYSIS - REVIEW OF REPRESENTATIVE APPLICATIONS

Supercritical fluid chromatography and extraction are investigated as techniques for analyzing surface coatings and many of the raw materials that go into their manufacture. Reactive oligomeric mixtures such as radiation curing coatings, polyisocyanate curing agents, and surface active agents are separated using capillary SFC with CO2. Polar oligomeric mixtures such as epoxy, vinyl, and phenol-formaldehyde resins can be separated with modified mobile phases on packed columns. Optimization of chromatographic separation through pressure composition and flow programming is highlighted. On-line supercritical fluid extraction-capillary supercritical fluid chromatography is used to extract and separate ultraviolet light stabilizers incorporated into a cured automotive clear coating. Optimization of conditions for the extraction of polymers is discussed.