Determination of acid and hydroxyl end-groups in endfunctionalized polystyrenes using 19F NMR

Abstract

Carboxyl-terminated polystyrene was esterified with 2,2,2-trifluoroethanol using a carbodiimide-mediated room temperature reaction, and hydroxyl-terminated polystyrene was fluoro-derivatized with trifluoroacetic anhydride. The soformed fluorine-containing esters were then quantitatively determined with 19F NMR, using α,α,α-trifluorotoluene as secondary standard. This provides a technique for the reliable determination of carboxylic acid and hydroxyl groups in small samples of polymers.