改性松香-缩合单宁酯的制备及性质

在微波辐照下,以吡啶作催化剂,通过缩合单宁与改性松香酰氯的O-酰化反应,以改性松香和不同级分或树种的缩合单宁为原料,合成了一系列改性松香-缩合单宁酯.利用UV、IR、TG-DTA和元素分析等方法对目标产物进行了分析和表征,并测试了它们的抗氧化性及其钠盐的表面活性.结果表明,改性松香-缩合单宁酯的油溶性普遍好于缩合单宁,在花生油中表现出良好的抗氧化性,且去氢枞酸-毛杨梅树皮缩合单宁酯的抗氧化性能最佳.改性松香-缩合单宁酯的钠盐比缩合单宁的钠盐具有更优良的表面活性,其降低表面张力能力强弱顺序为:HR-WT钠盐＞HR-ET钠盐＞DR-ET钠盐＞DR-WT钠盐＞DHA-WT钠盐≈DHA-MET钠盐＞DHA-ET钠盐＞ET钠盐;不同松香改性产物钠盐的表面张力和临界胶束浓度有一定差异,但差别不大,其中氢化松香改性产物钠盐的表面活性最好,歧化松香改性产物钠盐的表面活性次之,去氢枞酸改性产物钠盐的表面活性最差.改性松香-缩合单宁酯钠盐对苯的乳化力都超过了60min,具有很好的乳化能力.改性松香-缩合单宁酯钠盐起泡比顺序为:氢化松香-黑荆树树皮缩合单宁酯钠盐＞歧化松香-黑荆树树皮缩合单宁酯钠盐＞去氢枞酸-黑荆树树皮缩合单宁酯钠盐＞去氢枞酸-毛杨梅树皮缩合单宁酯钠盐＞毛杨梅树皮缩合单宁钠盐.

Preparation and Properties of Modified Rosin-condensed Tannins Esters

Under microwave irradiation and in the presence of pyridine as catalyst,a series of modified rosin-condensed tannins esters were synthesized by O-acylation reaction between condensed tannins and modified rosin chloride. The target products were analyzed and characterized by means of UV,IR,TG-DTA and elemental analysis. In addition,antioxidant activity and surface activity of the esters were determined. The test results showed that modified rosin-condensed tannins esters have better oil-solubility in peanut ...