To facilitate the reuse and recycling of polyvinyl chloride (PVC) to achieve sustainable development and new industrialization, the composition and mechanism of formation of volatiles during the flash pyrolysis of PVC were studied by thermogravimetry-Fourier transform infrared (TG-FTIR) and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). TG and derivative thermogravimetry (DTG) analyses indicated two main degradation stages during flash pyrolysis of PVC, namely dehydrochlorination of PVC and decomposition of dechlorinated-PVC. Simultaneously, the FTIR results revealed that the main functional groups in the pyrolysis process were H–Cl, -C-Cl, C–H, CH, and aromatic groups. The relative content of main volatiles was determined by Py-GC/MS, and decreased in the following order: aromatics > alkenes > hydrogen chloride (HCl) > chlorinated hydrocarbons. Specifically, the relative content of aromatics was as high as 76.790–81.809%, while that of HCl was in the range of 3.016–3.096%. The carbon number distribution and the relative content of main products obtained from the flash pyrolysis of PVC at different final temperatures were also analysed. According to the experimental results, the mechanism of formation of the main volatiles based on free-radical reactions was deduced in detail. Therefore, this study provides further details for deepening the understanding of the PVC pyrolysis process.

为了促进聚氯乙烯（PVC）的再利用和再循环以实现可持续发展和新型工业化，通过热重分析-傅里叶变换红外光谱（TG-FTIR）和热解法研究了PVC的快速热解过程中挥发物的组成和形成机理。气相色谱/质谱（Py-GC / MS）。TG和微分热重分析（DTG）分析表明，在PVC的快速热解过程中有两个主要的降解阶段，即PVC的脱氯化氢和脱氯的PVC的分解。同时，FTIR结果表明，热解过程中的主要官能团为H–Cl，–C–Cl，CH–H，CH，和芳香族基团。主要挥发物的相对含量通过Py-GC / MS确定，并按以下顺序降低：芳烃>烯烃>氯化氢（HCl）>氯化烃。具体而言，芳烃的相对含量高达76.790–81.809％，而HCl的相对含量在3.016–3.096％的范围内。还分析了在不同的最终温度下，PVC的快速热解得到的主要产物的碳数分布和相对含量。根据实验结果，详细推导了基于自由基反应的主要挥发物形成机理。因此，本研究为加深对PVC热解过程的理解提供了更多细节。