Thermal degradation and pyrolysis behavior of aluminum alginate investigated by TG-FTIR-MS and Py-GC-MS

The pyrolysis behavior of aluminum alginate is compared with that of alginic acid. The thermal degradation and pyrolysis behavior of aluminum alginate have been studied using a thermogravimetric analyzer coupled with Fourier transform infrared analysis and mass spectrometry (TG-FTIR-MS) and a pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS), respectively. TG-FTIR-MS and Py-GC-MS results indicated that the aluminum ions influenced the devolatilization gas products upon pyrolysis process. The pyrolysis of alginic acid was found to yield much more kinds of products than aluminum alginate was. And it suggested that the aluminum ions could strongly catalyze the fragments formed in the pyrolysis process of aluminum alginate to produce the less molecular weight and more stable products, such as carbon dioxide and furfural. The results indicated that the aluminum ions had the catalysis effect on the pyrolysis process of aluminum alginate. The possible thermal degradation mechanism of aluminum alginate was proposed according to the results of Py-GC-MS of aluminum alginate. The results of our study provide useful information for understanding the flame retardant mechanism of alginates.