Study on the thermal decomposition behavior and products of poly(vinyl alcohol) and its LiClO4 composites via Py/GC/MS

Poly(vinyl alcohol) (PVA) is a binder for electrically controlled solid propellants (ECSPs), whose combustion strongly depends on their decomposition characteristics. Thus, the effects of heating rate, pyrolysis temperature, and lithium perchlorate content on the thermal decomposition behavior and products of PVA and LiClO 4 /PVA composites were investigated via thermogravimetry (TG) and pyrolysis/gas chromatography/mass spectrometry (Py/GC/MS). The TG curves showed that the heating rate significantly influences the thermal decomposition behavior; according to the Py/GC/MS results, the major pyrolysis products of PVA were water, acetaldehyde, 2-butenal, and 2,4-hexadienal at 573 K and acetaldehyde, cyclic olefinic compounds, and aromatic hydrocarbons at 1173 K. The results also revealed that depolymerization is among the main decomposition mechanisms of LiClO 4 /PVA composites and using the optimal LiClO 4 content (40–56 mass%) could enhance the combustion efficiency of ECSPs.