中文摘要：

针对热固性聚氨酯三维网状交联结构，提出了基于机械物理法的回收工艺流程。采用RNG k-ε双方程湍流模型，对回收过程中的高速流场进行了数值模拟，得出转速和时间对降解效果的影响最大。最后，通过回收实验研究了材料物理性质及化学结构的变化。红外分析表明，当设备转速为1500r／min，粉碎时间超过40min时，热固性聚氨酯中的氨基甲酸酯基团在C～O键处会发生断裂，交联结构受到破坏，材料发生降解；进而重新获得热塑性特性，并可以通过热压成型的方法制造出新的热固性聚氨酯产品。

英文摘要：

Recycling process of waste thermosetting polyurethane was proposed based on mechanical and physical methods, assuming the plastics had a three-dimensional reticular cross-linkage body structure. Using RNG k-ε dual equation turbulence model, a high speed flow field numerical simulation in the smashing recovery process was completed and optimal parameters of materials degradation process were obtained. The experiment showed speed and time factors had the greatest impact on the process. Finally, the physical properties and morphology structure during the recycling were studied. ATR-FTIR analysis proved that carbamate group would break at C--O bonding when the device speed exceeded 1500 r/min and the experimental time exceeded 120 min. It meant that crosslinked structure was destroyed and the material resumed a thermoplastic behavior.