Síntese e caracterização da resina poliéster obtido a partir do produto natural norbixina, glicerol e anidrido ftálico

Abstract

Historically, polymers have Always been widely used, the first reports date back to the mid-century XIX. Currently, polymers are used for specific purposes and technical, however the monomers used in the synthesis of the polymer are important because they are determinants of the properties of the same. In this context polyesters based natural products attract attention by making possible the synthesis of polymers with different properties, such as the character of the hydrophobic, biocompatibility, biodegradability etc. The research aims to synthesize and characterize new polymeric material, a polyester obtained from the natural product norbixin, a substance extracted from annatto (Bixa Orellana L.), Glycerol a triálcool much used in organic syntheses and anadrido phthalic that function as plasticizers in synthetic resins, such as glyptal, alkyd resins and polyester resins. The synthesis was carried out by means of a reaction to the classic poliesterificação, performed in an open system under heating and agitation. After about 50 minutes and a temperature of 130 ° c, was added, as catalyst, the cobalt acetate. Keeping the temperature constant and equal to about 5 hours, the reaction mixture began to change phase, presenting the characteristics of plastic with a certain degree of viscosity. The completion of the polymerization, the material was cooled naturally to room temperature. Was executed all preparation required of the polymeric material for the study of its structural properties and thermal properties through the characterization techniques: Infrared Spectroscopy with Fourier transform (FTIR) spectroscopy, ultraviolet-visible (UV-vis), X-ray Diffraction (DRX), Frorescência of rays-X(FRX), Thermogravimetric Analysis (TGA) and Calorimetry Exploratory Differential (DSC). The analysis of the structural composition of the Spectroscopy FTIR showed the appearance of bands typical of carbonyl of ester (1720 cm–1) and reduction of the intensity of absorption of stretching O–H, which demonstrates a decrease of the character of hydroxyl groups, eliminated in the polycondensation reaction. The curves characterizing the thermal (TGA and DSC) showed that the material synthesized had values of phase transitions appreciable for polymeric materials, especially amorphous polymers with trends in thermoplastic.