Uracil derivatives are potential nontoxic thermal stabilizers of poly(vinyl chloride) (PVC) and have a better stabilization effect. 5,6‐diamino‐1,3‐dimethyluracil (DDU) was investigated as a thermal stabilizer for PVC. The stabilization effect of DDU was measured by thermogravimetric analysis, thermal aging test, and recording the time of the color change of the Congo red paper (Congo red test). Meanwhile, the processability of PVC stabilized by DDU was investigated through dynamic performance test. The results showed a better stabilizing effect compared with calcium stearate (CaSt₂) and zinc stearate (ZnSt₂). To explain the stabilization of DDU, the probable mechanism was suggested that DDU absorbed and chemically bonded with hydrogen chloride. Therefore, DDU could be used as a thermal stabilizer of PVC.

中文翻译：

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5,6-二氨基-1,3-二甲基尿嘧啶可提高聚氯乙烯的加工性能和热稳定性

尿嘧啶衍生物是聚氯乙烯（PVC）潜在的无毒热稳定剂，具有更好的稳定作用。研究了5,6-二氨基-1,3-二甲基尿嘧啶（DDU）作为PVC的热稳定剂。通过热重分析，热老化试验并记录刚果红纸的变色时间（刚果红试验）来测量DDU的稳定作用。同时，通过动态性能测试研究了DDU稳定PVC的可加工性。结果表明更好的稳定化效果与硬脂酸钙（CAST相比₂）和硬脂酸锌（硬脂酸锌₂）。为解释DDU的稳定性，可能的机理被认为是DDU吸收并与氯化氢化学键合。因此，DDU可以用作PVC的热稳定剂。