Abstract
The thermo-oxidative degradation of polyacetal resins and paraformaldehyde have been studied with non-isothermal thermogravimetric method. The evolved gases by the thermo-oxidative degradation of polyacetal resins and paraformaldehyde were identified by simultaneous thermogravimetry-differential thermal analysis-Fourier transform infrared spectroscopy (TG-DTA-FTIR). The polyacetal copolymer was more stable than the homopolymer since the DTG peak temperature of the copolymer was about 28 degrees higher than the peak of homopolymer. It was found that the activation energy (ΔE) for the thermal degradation of homopolymer, the copolymer and paraformaldehyde were 121.8kJ mol-1, 133.7kJ mol-1, and 79.8kJ mol-1, respectively. The value for the paraformaldehyde gives an agreement with the binding energy of OC-H bond. It was found that the thermo-oxidative degradation of polyacetal resin was accompainied by endothermic reaction and elimination of formaldehyde. In the case of the homopolymer, the desorption of formaldehyde gases was observed at the melting point.
