ОПТИМИЗАЦИЯ УСЛОВИЙ СИНТЕЗА ПОЛИЭТИЛЕНТЕРЕФТАЛАТА И ВЛИЯНИЕ КАТАЛИЗАТОРОВ НА ЕГО СВОЙСТВА

Abstract

In order to study the influence of the nature of the catalyst on the production process and the physicochemical properties of polyethylene terephthalate, samples were synthesized using catalysts based on antimony and titanium. Optimal catalyst concentrations were established for the production of polyethylene terephthalate with values close to those of industrial designs EKOPET samples: the characteristic viscosity (0.55-0.75 dl/g), melting temperature (max. 256°С), color number (L* ≥ 82.0; b * -1.5 ± 2.0) and acetaldehyde content (max. 1.0 ppm). The structure and properties of synthesized polyethylene terephthalate samples were studied using the methods of infrared spectroscopy and differential scanning calorimetry; transparency (L*) and color (b*) indicators, intrinsic viscosity, the amount of diethylene glycol, acetaldehyde and the content of terminal carboxyl groups were determined. Questions about the influence of nature, as well as the quantitative ratio of the catalyst on the indicators of color, transparency, intrinsic viscosity and the content of terminal carboxyl groups were discussed. It was revealed that titanium-containing compounds, in comparison with antimony catalysts, increase catalytic activity, which helps reduce the duration of the production process and produce polyethylene terephthalate with high molecular weight characteristics.