Composition and microstructure determination of a latex system by pyrolysis gas chromatography

摘要

The composition and microstructure of polymers in a latex system have been studied by pyrolysis gas chromatography (Py-GC). Traditionally, when latex systems have been analyzed, all polymeric materials have been assumed to be in the emulsion phase,and the aqueous phase contains some additives, surfactants, initiators, and chain-transfer agents. The polymeric materials in the aqueous phase will easily be overlooked because most analytical approaches do not perform any detailed polymer analysis of the aqueous phase. In addition to that, the polymer in the aqueous phase generally contains acid or alcohol functional groups in order to be dissolved/stabilized in the aqueous phase. Since monomers containing acid or alcohol functional groups are not readily detected in most pyrolysis experiments, the Py-GC study of these types of polymers always has some degree of difficulty. However, the composition and microstructure analysis can be accomplished by prepyrolysis derivatization with an appropriate derivatization reagent to convert the acid functional group to its ester. After prepyrolysis derivatization followed by Py-GC, the composition of polymer can be obtained from calculations based on relative monomer intensities. The microstructure can be explored by comparing the pure and hybrid trimer peak pattern with appropriate standards. [References: 16]