Functionalization of cross-linked poly(styrene) in the preparation of a PET target material

In an effort to prepare an improved carbon-rich target material for the generation of [13N]ammonia for use in PET, styrene was polymerized and cross-linked with various percentages of divinylbenzene (DVB). The resulting copolymers were then sulfonated and nitrated and the degree of substitution was determined by elemental analysis. As expected, increased levels of DVB sterically hindered substitutions of the aromatic ring.