磷酸酯改性丙烯酸水性防锈漆的制备

Preparation of waterborne antirust phosphate ester-modified acrylic varnish

以五氧化二磷与甲基丙烯酸羟丙酯自制了功能性磷酸酯单体,并与丙烯酸、甲基丙烯酸甲酯、丙烯酸丁酯、丙烯酸羟丙酯等单体,以偶氮二异丁腈为引发剂,在乙二醇丁醚中进行聚合,合成了改性丙烯酸树脂。将其与固化剂氨基树脂混合即得一种水性防锈漆。考察了原料用量对漆膜性能的影响,得到最优制备条件为:甲基丙烯酸羟丙酯与五氧化二磷的摩尔比为2.0,磷酸酯用量(占单体总质量,后同)5%,丙烯酸用量20%,甲基丙烯酸甲酯用量35%。所得漆膜可耐5%Na Cl溶液浸泡30 d,冲击强度50 kg·cm,附着力0级,柔韧性3 mm,铅笔硬度HB。

A functional phosphate ester monomer was prepared from phosphorus pentoxide and 2-hydroxypropyl methacrylate, and then polymerized with other monomers such as acrylic acid, methyl methacrylate, butyl acrylate, and hydroxypropyl acrylate, using azobisisobutyronitrile as initiator in ethylene glycol butyl ether, forming a modified acrylic resin. A waterborne antirust varnish was obtained by mixing the modified acrylic resin with amino resin as a curing agent. The effects of the contents of raw materials on properties of the cured film obtained therefrom were studied. The optimal preparation parameters were obtained as follows： the molar ratio of 2-hydroxypropyl methacrylate to phosphorus pentoxide is 2.0, and the amount（with respect to the total mass of monomers） is 5 wt.% for phosphate ester, 20 wt.% for acrylic acid, and 35 wt.% for methyl methacrylate. The film obtained therefrom can endure a 30-day immersion in 5% Na Cl, and has an impact strength of 50 kg·cm, an adhesion strength of 0 grade, a flexibility of 3 mm, and a pencil hardness of HB.