The combination of liquid chromatography and mass spectrometry techniques for the characterization of aliphatic polyesters
Aliphatic polyesters are industrially implemented in high performance coatings, paints and varnishes, however it is typically difficult to correlate the resulting properties with the synthesis parameters as these polymers vary in reactivity and application properties. Due to the stepwise polymerization mechanism, it is often assumed that copolyester synthesis by direct polyesterification will lead to randomized products. The formation of cyclic products by transesterification allows even further randomization, enabling a highly complex system. The different methods of polymer chromatography in combination with sophisticated spectroscopic techniques are useful tools for enabling the full description of the molecular heterogeneity of these complex polyesters. Through the use of SEC, HPLC, MALDI-TOF and ESI-MS information was obtained on the extent of heterogeneity found during the synthesis of model polyesters based on maleic anhydride and phthalic anhydride with propylene glycol which serve as building blocks for the more complex industrial variety. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.