Effect of Glycol Length on the Thermal Properties of Polyesters: PET, PTT, PBT Case Studies

Polyethylene terephtalate (PET), Polybutylene terephthalate (PBT) and Polypropylene terephthalate (PPT) were synthesized in two steps: direct esterification of ethylene glycol (EG), butane diol (BDO), propane diol (1,3-PDO) and terephthalic acid (TPA) followed by polycondensation. Synthesized polyesters were characterized by Fourier Transform Infrared Spectroscopy (FTIR). Intrinsic viscosity was measured by Ubbelhode viscometer as an indication of reaction progress. Thermal properties were investigated by differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA) and dynamic mechanical thermal analysis (DMTA). It was observed that PET had the highest Tg among the other polyesters and PBT had the lowest. The same result was seen for their Tm and initial degradation temperature. Finally prepared polymers evaluated from the view point of desired molecular weight and thermal properties.

کلیدواژه ها:

Synthesis ، Polyethylene terephtalate (PET) ، Polybutylene terephthalate (PBT) and Polypropylene terephthalate (PPT) ، Thermal analysis