Synthesis and Relaxation Properties of bis(5-Hydroxypenthyl)Phthalate - the Model Oligoester to Study the Relaxation Properties of Polyesters

The description of polymer relaxation proprieties is the way to characterize the influence of polymer structure on its useful proprieties of stability and resistance. To perform physicochemical profiles of polymers the synthesis and investigation of model compounds was required. The instrumental methods such as NMR, FTIR, dielectric spectroscopy were used. The results of the experiments allowed us to improve the technology of the synthesis processes and the extension of the range of their usage. Moreover the obtained polymers were more stable and more resistant to degradation. To acquire the profile of the relaxation properties of the linear, hyperbranched and dendrite unsaturated polyester resins, the synthesis of the oligoesters as the model compounds was performed. Pentane‐1,5‐diol phthalic anhydride was used as substrate of the process. The structures of the obtained model compound were confirmed by elemental analysis and 1H NMR and FTIR spectroscopy. Measurements of the relaxation processes of the model compound were also done. The determination of the α, β and β′ relaxation processes for model oligoesters allow us to describe the practical properties of commercial compounds. The description of model relation of the relaxation process may facilitate the interpretation of the dependence between useful properties of polyesters and their molecular structure.