自干型水性醇酸树脂的合成研究

Study on the synthesis of air dry water- based alkyd resin

采用偏苯三酸酐（TMA）制备了水性醇酸树脂,通过涂膜性能测试及红外光谱分析研究了反应中各项因素对水性醇酸树脂性能的影响。结果表明,最佳的反应条件如下：采用亚麻油、甘油、邻苯二甲酸酐（PA）、TMA为原料,油与甘油物质的量比1∶2.07,油度45%~50%,醇超量7%,最终酸值（KOH）50~55 mg/g。醇解催化剂选用LiOH,添加质量分数为油量0.04%。PA的酯化温度从180℃开始以20℃/h的速度升温至235℃,TMA的酯化温度为170~180℃。助溶剂选用丙二醇甲醚,中和剂选用N,N’-二甲基乙醇胺,中和度控制在100%,pH约在7.5~8左右。最终得到了棕色透明的水性醇酸树脂,其干燥性能、光泽、硬度、柔韧性等性能较好。

The trimellitic anhydride（ TMA） was used to synthesis the water- based alkyd resins. The effect of each factor on the properties of product resin was investigated by the testings of film properties and FT- IR analysis. The results showed that the optimum synthesis conditions were as followed： using linseed oil,glycerol,phthalic anhydride and TMA as raw materials,molar ratio of oil and glycerol 1∶ 2. 07,oil length 45%- 50%,excessive polyalcohol 7%,final acid value（ KOH） 50- 55 mg /g and 0. 04wt% LiOH as alcoholysis catalyst. The esterification temperature of PA was 180 ℃ at first and then was heated to 235 ℃ at the rate of 20 ℃ /h. The esterification temperature of TMA was 170- 180 ℃. The propylene glycol monomethyl ether and N,N’- dimethyl ethanolamine were usd as cosolvent and neutralizer,respectively. The neutralization was controlled at 100% and the pH value of product was about 7. 5- 8. A transparent brown water- based alkyd resin was finally obtained and its drying properties,gloss,hardness,flexibility and other properties were very well.