Abstract：
Aminolysis is widely recognized as a valuable chemical route for depolymerizing polymeric materials containing ester, amide, or urethane functional groups, including polyurethane foams. Bio-based polyurethane foams, pristine and reinforced with 40 wt% of sustainable fillers, were depolymerized in the presence of bio-derived butane-1,4-diamine, BDA. A process comparison was made using fossil-derived ethane-1,2-diamine, EDA, by varying amine/polyurethane ratio (F/A, 1:1 and 1:0.6). The obtained depolymerized systems were analyzed by FTIR and NMR characterizations to understand the effect of both diamines on the degradation pathway. The use of bio-based BDA seemed to be more effective with respect to conventional EDA, owing to its stronger basicity (and thus higher nucleophilicity), corresponding to faster depolymerization rates. BDA-based depolymerized systems were then employed to prepare second-generation bio-based composite polyurethane foams by partial replacement of isocyanate components (20 wt%). The morphological, mechanical, and thermal conductivity properties of the second-generation polyurethane foams were evaluated. The best performances (σ10 %=71 ± 9 kPa, λ = 0.042 ± 0.015 W∙ m-1 ∙K-1) were attained by employing the lowest F/A ratio (1:0.6); this demonstrates their potential application in different sectors such as packaging or construction, fulfilling the paradigm of the circular economy.
摘要：
氨解被广泛认为是解聚含酯的聚合材料的有价值的化学途径，酰胺,或氨基甲酸酯官能团，包括聚氨酯泡沫。生物基聚氨酯泡沫，原始和用40重量%的可持续填料增强，在生物衍生的丁烷-1,4-二胺的存在下解聚，BDA.使用化石衍生的乙烷-1,2-二胺进行了工艺比较，EDA,通过改变胺/聚氨酯比(F/A，1：1和1：0.6）。通过FTIR和NMR表征分析获得的解聚体系,以了解两种二胺对降解途径的影响。与传统的EDA相比，生物基BDA的使用似乎更有效，由于其更强的碱性(因此更高的亲核性)，对应于更快的解聚速率。然后采用基于BDA的解聚体系，通过部分替代异氰酸酯组分（20wt％）来制备第二代生物基复合聚氨酯泡沫。形态学,机械,并对第二代聚氨酯泡沫塑料的导热性能进行了评价。最佳性能(σ10%=71±9kPa，λ=0.042±0.015W·m-1·K-1）通过采用最低的F/A比（1：0.6）获得；这表明它们在包装或建筑等不同领域的潜在应用，实现循环经济的范式。
