生物基甘油酯类增塑剂的合成及增塑性能

Synthesis and properties of bio-based glyceryl ester plasticizers

摘要:

以甘油和不同结构脂肪酸（辛酸、2-乙基己酸、戊酸和2-甲基丁酸）为原料，采用直接酯化法制备得到4种不同结构的甘油衍生脂肪酸酯，作为增塑剂用于聚氯乙烯（PVC）。利用FTIR和1HNMR分析增塑剂的结构与纯度，将4种增塑剂塑化的PVC试片与邻苯二甲酸二（2-乙基己）酯（DEHP）塑化的PVC试片进行对比研究。结果表明，与DEHP塑化的PVC试片比，甘油三戊酸酯PVC试片的断裂伸长率提高了151%；甘油三辛酸酯PVC试片的初始降解温度提高了12.3 ℃；甘油三（2-甲基丁酸）酯PVC试片的耐挥发性更好，均具有替代DEHP的潜力。另外，分析增塑剂的构效关系，发现分子结构中支链多的增塑剂与PVC之间的相容性和耐抽出性更好，但热稳定性和耐挥发性降低。

Abstract:

Using glycerol and fatty acid with different structures (octoic acid, 2-ethylhexic acid, pentic acid and 2-methylbutyric acid) as raw materials, four glyceride-derived fatty acid esters with different structures were prepared by direct esterification method, and were applied as plasticizers for PVC. The structure and purity of the plasticizers were analyzed by FTIR and 1HNMR. The PVC films plasticized by the four plasticizers were studied and compared with the PVC film plasticized by bis(2-ethylhexyl) phthalate (DEHP). The results showed that, compared with the PVC film plasticized by DEHP, the percentage of breaking elongation of glycerol trivalerate was increased by 151% in the plastic PVC film, the initial degradation temperature of the glycerin tricaprylate plasticized PVC film was 12.3 ℃ higher, the extraction resistance of glyceryl tri(2-methylbutyl) ester plasticized PVC film was better, indicating the potential to replace DEHP. Furthermore, the analysis of the relationship between the structure and performance of the plasticizers found that the PVC plasticized by plasticizers with more branches had better compatibility and extraction resistance, but the thermal stability and volatility resistance were weaker.