Synthesis and Characterization of Polyester Derived from Glycerol and Its Application as an Adhesive on Different Adherents

With the increase in the supply of glycerol and its economic devaluation, it is important to develop strategies that add value to this substance. Among the various alternatives, one application is its use as a precursor in the synthesis of new polyesters. Therefore, this work describes the condensation reaction of glycerol with valeric acid, obtaining functionalized glycerol, which was used in the polycondensation reaction with terephthalic acid. The samples were characterized by infrared spectroscopy, thermogravimetric analysis, hydrogen nuclear magnetic resonance and differential scanning calorimetry. Spectroscopic analyses confirmed the conversion of the reagents into esters and polyesters. The polyesters showed superior thermal stability than the individual components, a glass transition temperature of -3.8 degrees C and adhesive properties on glass, wood, paper and rigid polyvinyl chloride substrates. The adhesive capabilities of the samples were compared with those of commercial adhesives already established in the Brazilian market. Samples of polyesters synthesized through the reaction between functionalized glycerol and terephthalic acid showed adhesive behavior in the range of mechanical resistance observed in commercial adhesives, with an elastic modulus ranging from 60.9 +/- 36.0 MPa to 162.1 +/- 102.4 kPa, depending on the type of adhesive substrate, behaving either as an elastic and/or thermoplastic adhesive.