PRODUCCIÓN DE POLÍMEROS BIODEGRADABLES MEDIANTE LA MODIFICACIÓN DEL PET CON APL Y QUITOSANO

Abstract

In order to reduce the PET degradation time in this work, virgin and recycled Polyethyleneterephthalate (PET)-based blends are presented; polylactic acid (PLA) and chitosan, biodegradable polymeric materials, are added to PET (matrix), and an insertion polymeric in the main chain of PET is expected. The structural interaction and miscibility were investigated by infrared analysis (FTIR), Diferential Scanning calorimetry (DSC), X-Ray diffraction (XRD) and Scanning Electron Microscopy (SEM). The polymeric degradation of the blends was carried out in an accelerated weathering chamber and by burying in compost. The degradation characteristics and the structurals changes, weight loss percent and the superficial damages were determinated. Subsequent, PET/chitosan and PET/PLA blends were obtained by ball milling technique with the purpose of studying the interaction between phases and evaluated particle size and the structural and thermal behavior by the characterization using FTIR, DSC, XRD and SEM. Miscible polymer blends with physical interactions were obtained by the extrusion process. Biopolymers does not affect the crystalline structure of the conventional matrix, however there is a shift in the melting point at higher temperatures with the addition of APL and chitosan. The blends with APL (85/15) and chitosan (95/5) with PET virgin and recycled have the best properties of degradation. The results of mechanical milling suggest that the energy generated in the system is not sufficient to generate new bonds, however, the milling influences in the crystalline structure and the thermal behavior of the blends. From SEM was achieved to detect the welding and the fracture induced by mechanical milling.