Experimental investigation and numerical modeling of oxidative pyrolysis mechanism of mining PVC cable sheath

作者：Jinlong Zhao, Hanchao Ma, Hong Huang, Jianping Zhang, Youliang Chen · 发表于：Journal of Thermal Analysis and Calorimetry · 年份：2022 · DOI：10.1007/s10973-022-11723-8 · 被引用次数：16 · 研究领域：Thermal and Kinetic Analysis、Polymer Science and PVC、Flame retardant materials and properties

Abstract Cables modified with flame retardants are widely used in the coal mining process to enhance their fire safety performance. This paper investigates experimentally and numerically the thermo-oxidative degradation process of PVC-based mining cable sheath, which consists of PVC resin and plasticizers (Phthalate esters), fillers (Calcium carbonate), and flame retardant (Antimony trioxide) as additives. Thermogravimetry coupled with Fourier transform infrared spectroscopy (TG-FTIR) experiments were performed at different heating rates in an air atmosphere. TG results showed that the decomposition processes of mining PVC cable sheath are more complicated than those of pure PVC with additional degradation steps, which was further confirmed by FTIR gas analysis. A deconvolution method was used to distinguish the independent reactions from the overlapped derivative thermogravimetric (DTG) peaks. It was found that the whole degradation process can be divided into seven steps, based on which an oxidative pyrolysis model was developed: pyrolysis of plasticizers (steps 1 and 2), dehydrogenation (step 3), emission and combustion of volatile fraction (step 4), carbon combustion (step 5), oxidative pyrolysis of complicated additives (step 6), and decomposition of residues (step 7). The kinetic triplets (activation energy, pre-exponential factor, and reaction model function) for each reaction were firstly calculated using three commonly used model-free methods and then further optimiz...