耐水煮水性聚酯氨基烤漆的制备及性能研究

Study on preparation and properties of water-boiling-resistant waterborne polyester amino baking paint

以二羟甲基丙酸为亲水单体,间苯二甲酸、1,4?环己烷二甲酸、二聚酸等为酸类单体,新戊二醇、1,4?环己烷二甲醇、二聚醇、三羟甲基丙烷等为醇类单体,在钛酸四丁酯的催化下,制备了水性聚酯树脂。再经过添加水性氨基树脂,制得耐水煮性好的水性氨基烤漆。研究了二聚酸和二聚醇的用量,不同氨基树脂,以及聚酯树脂与氨基树脂的质量比对烤漆性能的影响。结果表明,当二聚酸和二聚醇的质量分数分别为15%和12%时,所制备的水性聚酯树脂与Cymel 303氨基树脂以质量比3.0∶1配合,可以获得综合性能良好的氨基烤漆,其漆膜的附着力为0级,硬度大于H,60°光泽达到103,耐水煮时间超过3h,耐丁酮擦拭超过100次,正反耐冲击性(1kg)均大于50cm。

A waterborne polyester resin was prepared with 2,2-bis(hydroxymethyl)propionic acid as hydrophilic monomer,isophthalic acid,1,4-cyclohexanedicarboxylic acid,and dimer acid as acid monomers,and neopentanediol,1,4-cyclohexanedimethanol,dimer diol,and trimethylolpropane as alcohol monomers under catalysis of tetrabutyl titanate,and then mixed with waterborne amino resin to prepare a waterborne baking coating with good resistance to water boiling for metals.The effects of the amounts of dimer acid and dimer diol,different amino resins,as well as the mass ratio of polyester resin to amino resin on the properties of amino baking paint were studied.The results showed that an amino baking paint with good comprehensive performance could be obtained from the waterborne polyester resin prepared with 15wt.%dimer acid and 12wt.%dimer diol in combination with a Cymel 303 amino resin at a mass ratio of 3:1.The coating obtained therewith had the following properties:0-grade adhesion,pencil hardness higher than H,60°glossiness up to 103,anti-water boiling time longer than 3 hours,butanone rubbing resistance more than 100 times,and failure height at least 50 cm for an 1-kg impact on both sides of the test specimen.