Changes in the composition and structure at PET-waste processing into building materials

Abstract

The results of studies of the composition and structure of polyethylene terephthalate in the process of thermomechanical processing of polymeric wastes as well as properties of waste products obtained on the basis of waste are presented. Methods of infrared spectroscopy, differential thermal analysis and thermogravimetry, as well as standard methods for manufacturing and testing the technical properties of samples of structural building products were used. As a result of thermomechanical processes during re-melting of polyethylene terephthalate waste, the number of hydroxyl groups in the polymer composition decreases, due to the possible cross-linking and polycondensation of macromolecules through terminal hydroxyl and unactivated carboxyl groups. In this case, conformational rearrangements take place in the structure of polyethylene terephthalate. When thermomechanical processing of secondary PET with rapid cooling of the melt, the temperature of the onset of subsequent melting decreases, which allows to reduce power consumption in melting-mixing units during the process of manufacturing construction products. Construction and technical properties of secondary PET as binder composite building materials allow to obtain potentially durable products with structural strength and high decorative.