Molecular Crystals and Liquid Crystals, Vol.483, 155-162, 2008
Study of the cross-linking process of model oligoesters by DMTA method
Some oligoesters were synthesized in order to study changes of the useful properties of hyper-branched unsaturated polyesters. The determination of the polymer relaxation properties allows for characterization of their structure. Useful properties of the polymers such as stability and persistence depend on their structure. The aim of the investigation was to obtain model oligoesters with low molecular weight and to study their properties by spectroscopic and the dynamic mechanical thermal analysis (DMTA) methods. The synthesis was performed with the use of ethylene glycol and the mixture of maleic anhydride and phthalic acid which allowed us to obtain linear unsaturated polyesters. The cross-linking process of synthesized model oligoesters was performed using styrene as a cross-linking agent. The NMR and IR spectroscopy and elemental analysis were used for the description of purity and the structure of the obtained products. Relaxation properties of the synthesized oligoesters, course of their cross-linking and relaxation properties of the cross-linked products were studied by DMTA methods. In the synthesized oligoesters and cross-linked products alpha and beta-relaxation processes were observed.