A method for preparing an aqueous polyurethane dispersion includes the following steps. The method characterized in that it introduces an ethoxy group to sodium ethylenediamine sulfonate (H2N—CH2CH2NHCH2CH2SO3Na) serving as an anionic chain extender to form sodium ethylenediamino ethoxyethyl sulfonate (H2NCH2CH2NHCH2CH2OCH2CH2SO3Na). Next, hydrophilic groups of sodium ethylenediamino ethoxyethyl sulfonate are used to prepare an aqueous polyurethane to improve the flowability of the resin, in which the polyurethane prepolymer has an isocyanate group at its end. More than one acrylate monomer is used for dilution and reduction of viscosity, and hydrophilic and amine groups containing sulfonate is used for water dispersion and to carry out a chain extension reaction. After that, an initiator is added for acrylic polymerization, so as to modify polyurethane with graft acrylic.
一种制备聚
氨酯
水性分散体的方法包括以下步骤。该方法的特点是在作为阴离子扩链剂的
乙二胺磺酸钠(
H2N-CH2C HCH2CH2SO3Na)中引入乙氧基,形成
乙二胺乙氧基
乙基磺酸钠( CH2C HCH2CH2OCH2CH2SO3Na)。接着,用
乙二胺乙氧基
乙基磺酸钠的亲
水基团制备
水性聚
氨酯,以改善
树脂的流动性,其中聚
氨酯预聚物的末端带有
异氰酸酯基团。使用一种以上的
丙烯酸酯单体来稀释和降低粘度,使用含
磺酸盐的亲
水基团和胺基团来进行
水分散和链延伸反应。然后加入
引发剂进行
丙烯酸聚合,从而用接枝
丙烯酸对聚
氨酯进行改性。