Wageningen Food and Biobased Research, Wageningen University and Research, P.O. Box 17, 6700 AA Wageningen, The Netherlands.
ACS Macro Lett. 2021 Dec 21;10(12):1616-1621. doi: 10.1021/acsmacrolett.1c00676. Epub 2021 Dec 9.
Poly(ethylene furanoate) (PEF) is widely advocated as a renewable alternative to the fossil-based polyester poly(ethylene terephthalate) (PET). Whereas the UV stability of PET is well-studied, little is known for PEF. Here, we compare the UV stability of both polyesters after 500 h of UV irradiation in a Q-SUN xenon arc chamber. Both the virgin and irradiated polyesters were characterized by FTIR, SEC, DSC, NMR, TGA, and MALDI-TOF MS. PET showed only minor signs of degradation under the applied test conditions, while PEF showed significant discoloration as well as evidence of both cross linking/chain extension and chain scission. Also, the thermal properties and the ability to crystallize of PEF were severely impacted by UV irradiation. Although a detailed study on the degradation mechanism is out of the scope of this work, we found indications that Norrish type I and II degradation reactions play an important role in the UV degradation of PEF.
聚呋喃二酸乙二酯（PEF）被广泛认为是一种可再生的聚酯替代品，可以替代基于化石的聚对苯二甲酸乙二醇酯（PET）。虽然 PET 的紫外线稳定性已经得到了很好的研究，但对于 PEF 却知之甚少。在这里，我们在 Q-SUN 氙弧室内对两种聚酯进行了 500 小时的紫外线照射，比较了它们的紫外线稳定性。对原始和辐照后的聚酯都进行了傅里叶变换红外光谱（FTIR）、凝胶渗透色谱（SEC）、差示扫描量热法（DSC）、核磁共振（NMR）、热重分析（TGA）和基质辅助激光解吸电离飞行时间质谱（MALDI-TOF MS）分析。在应用的测试条件下，PET 只显示出轻微的降解迹象，而 PEF 则表现出明显的变色，以及交联/链延伸和链断裂的证据。此外，PEF 的热性能和结晶能力也受到紫外线照射的严重影响。虽然详细的降解机制研究超出了本工作的范围，但我们发现表明 Norrish 型 I 和 II 降解反应在 PEF 的紫外线降解中起着重要作用。
