一种性能良好的自干型水性醇酸树脂的制备

Preparation of a high-performance air-drying waterborne alkyd resin

以亚麻油、季戊四醇、三羟甲基丙烷、氢氧化锂、邻苯二甲酸酐、苯甲酸、偏苯三酸酐、乙二醇丁醚和三乙胺为主要原料,采用成盐法合成了一种自干型水性醇酸树脂。考察了油度、中和前树脂酸值、pH、助溶剂种类和醇超量对水性醇酸树脂及以其所制面漆性能的影响,得到最优制备条件为:pH控制在8左右,中和前树脂的酸值(以KOH计)为50～60 mg/g,油度为50%,乙二醇丁醚(助溶剂)10%(相对于树脂质量),醇超量6%。用自制树脂配制的面漆具有以下突出性能:表干时间20 min,实干时间6 h,60°光泽94,铅笔硬度H,耐水性超过360 h。

An air-drying waterborne alkyd resin was synthesized from linseed oil, pentaerythritol, trimethylolpropane,lithium hydroxide, phthalic anhydride, benzoic acid, trimellitic anhydride, ethylene glycol butyl ether, and triethylamine by salt formation method. The effects of oil content, acid value prior to neutralization, pH value, type of cosolvent, and alcohol excess on the properties of waterborne alkyd resin and the topcoat prepared therefrom were studied. The optimal preparation conditions were obtained as follows: pH value 8, acid value 50-60 mg KOH per gram, oil content 50%, ethylene glycol butyl ether 10%(with respect to the mass of resin) as cosolvent, and alcohol excess 6%. The topcoat prepared with the home-made resin had the following properties: tack-free time 20 min, practical drying time 6 h, 60° glossiness 94, pencil hardness H, and water resistance over 360 hours.