A series of bio-based diester plasticizers with various alkyl chain asymmetry and the same molecular weight were designed and synthesized, using renewable 5-hydroxymethyl-2-furancarboxylic acid (HFCA) as the raw material. The chemical structures of the HFCA-based plasticizers were characterized by Fourier transform infrared and nuclear magnetic resonance (¹H NMR and ¹³C NMR). Besides, the influence of alkyl chain asymmetry on plasticization properties of the HFCA-based plasticizers in poly(vinyl chloride) (PVC) blends was also investigated. It was found that increasing the alkyl chain asymmetry of the diester plasticizer and keeping the molecular weight unchanged simultaneously could further improve its plasticizing efficiency, without sacrificing its volatility resistance and exudation resistance. The results showed that this study provided a new approach for further optimizing the overall properties of the asymmetric diester plasticizers.

中文翻译：

---

聚氯乙烯不对称烷基链HFCA增塑剂的设计与合成

以可再生的5-羟甲基-2-呋喃甲酸（HFCA）为原料，设计合成了一系列具有不同烷基链不对称性和相同分子量的生物基二酯增塑剂。HFCA 基增塑剂的化学结构通过傅里叶变换红外和核磁共振（¹ H NMR 和¹³C核磁共振）。此外，还研究了烷基链不对称性对聚氯乙烯 (PVC) 共混物中基于 HFCA 的增塑剂的增塑性能的影响。研究发现，增加二酯增塑剂的烷基链不对称性，同时保持分子量不变，可以进一步提高其增塑效率，同时不牺牲其抗挥发和抗渗出性。结果表明，该研究为进一步优化不对称二酯增塑剂的整体性能提供了一种新方法。