Split‐phase alcoholysis of flexible polyurethane (PU) foam yields an apolar phase containing the recycled polyether polyol, and a lower, polar phase of the alcoholyzing agent and aromatic compounds. However, multiple purification steps are required to render the polyether polyol suitable for synthesis of new flexible PU foams; the unfavorable mass balance limits industrial applications. In this work, 2‐pyrrolidone was identified as a performant additive for accelerating the dissolution and depolymerization process. By applying a lactam to PU foam in a weight ratio of 0.1:1, the glycol to PU foam weight ratio can be decreased from 1.5:1 to only 0.5:1, without loss of purity or yield of the recycled polyether polyol. Diglycerol was discovered as a novel, promising alcoholyzing agent; it allows the recycling of the polyether polyol in high purity (97 %) and excellent yields (98 %), and after a single washing with diglycerol, a sufficiently low hydroxyl value (61 mg_KOH g⁻¹) is reached. The recycled polyether polyol can replace the virgin polyether polyol (48 mg_KOH g⁻¹) for up to 50 % in the synthesis of new flexible PU foams with effects on the foam quality that stay within the limits of generally accepted specifications. A first step towards the valorization of the lower phase was also taken by applying hydrolysis of the newly formed carbamates to toluenediamines, which are readily reintegrated in new PU foams.

中文翻译：

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通过分相醇解回收软质聚氨酯泡沫：识别添加剂和醇解剂以达到更高的效率。

软质聚氨酯 (PU) 泡沫的分相醇解产生含有回收聚醚多元醇的非极性相，以及醇解剂和芳香族化合物的低极性相。然而，需要多个纯化步骤才能使聚醚多元醇适合合成新型软质聚氨酯泡沫；不利的质量平衡限制了工业应用。在这项工作中，2-吡咯烷酮被确定为一种加速溶解和解聚过程的高性能添加剂。通过以 0.1:1 的重量比应用内酰胺与 PU 泡沫，乙二醇与 PU 泡沫的重量比可以从 1.5:1 降至仅 0.5:1，而不会损失回收聚醚多元醇的纯度或收率。二甘油被发现是一种新型、有前途的醇解剂；它允许以高纯度（97％）和优异的收率（98％）回收聚醚多元醇，并且在用二甘油单次洗涤后，达到足够低的羟值（61mg _KOH  g ^{-1 ）。}在新型软质聚氨酯泡沫的合成中，回收的聚醚多元醇可以取代原始聚醚多元醇（48 mg _KOH  g ^-1）高达 50%，对泡沫质量的影响保持在普遍接受的规格范围内。通过将新形成的氨基甲酸酯水解成甲苯二胺，还迈出了实现下相增值的第一步，甲苯二胺很容易重新整合到新的聚氨酯泡沫中。