Thermal Field-Flow Fractionation of Acrylic Copolymers

A new thermal field-flow fractionation (ThFFF) method has been developed for the separation and analysis of polyacrylates and acrylic-styrene copolymers. This important class of polymers is commonly used as pressure sensitive adhesives, in coatings and paintings, and as the basis for polyelectrolyte materials. The structure and chemical composition of these polymers play a vital role in the end use of these materials. It is important to accurately analyze and characterize these materials to better understand their structure-property relationships. These polymers have not previously been investigated by ThFFF. Size exclusion chromatography is commonly used to separate these materials. However, SEC is a size based separation and will not differentiate between copolymers of different chemical composition, or between polymers of different architectures if they are the same size. Thermal FFF, on the other hand, separates analytes according to differences in their thermal diffusion (DT) and normal diffusion (D) as expressed in the retention parameter (λ) equation below.