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1.发明授权Process of preparing aqueous solutions of melamine-formaldehyde condensation products having anionic sulfo groups 失效制备具有阴离子磺基的三聚氰胺 - 甲醛缩合产物的水溶液的方法
公开(公告)号：US3985696A
公开(公告)日：1976-10-12
申请号：US523555
申请日：1974-11-14
摘要： Aqueous solutions of melamine-formaldehyde and melamine-urea-formaldehyde condensation products having anionic sulfo groups in concentrations as high as 50% by weight may be prepared in a three-stage process. In the first stage, melamine or a mixture of melamine with up to 40 mole-% urea, formaldehyde, and an alkali metal sulfite are condensed in aqueous solution at 60.degree.-80.degree.C and pH 10-13 until the solution is free from readily detectable amounts of sulfite. In the second stage, condensation is continued at pH 3.0-4.5 for 30 to 90 minutes. In the third stage, a temperature of 70.degree. to 95.degree.C and a pH of 7.5 to 9.0 are maintained until a sample of the solution, when diluted to 20% solids by weight, has a viscosity of 5 to 40 centipoises at 20.degree.C.
摘要翻译： 具有浓度高达50重量％的阴离子磺基的三聚氰胺 - 甲醛和三聚氰胺 - 脲 - 甲醛缩合产物的水溶液可以在三步法中制备。 在第一阶段，三聚氰胺或三聚氰胺与高达40摩尔％的尿素，甲醛和碱金属亚硫酸盐的混合物在60℃-80℃和pH 10-13的水溶液中冷凝直到溶液不含 容易检测量的亚硫酸盐。 在第二阶段，在pH3.0-4.5下继续冷凝30至90分钟。 在第三阶段中，保持70℃至95℃的温度和7.5至9.0的pH，直到溶液样品稀释至20重量％固体时，在20℃下的粘度为5至40厘泊 C。
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公开(公告)号：US3941734A
公开(公告)日：1976-03-02
申请号：US461614
申请日：1974-04-17
申请人： Alois Aignesberger , Paul Bornmann
发明人： Alois Aignesberger , Paul Bornmann
摘要： The aqueous melamine resin solutions prepared according to the process of U.S. Pat. No. 2,730,516 by sequential condensation of a sulfite bearing, aqueous solution of melamine and formaldehyde at alkaline and acid pH and subsequent neutralization is stabilized by preliminary condensation of the melamine and formaldehyde prior to addition of the sulfite and by refluxing the ultimate condensation mixture at pH 8.5 for 1 hour or more. Concrete mixtures prepared with the stabilized resin solutions cure more rapidly.
摘要翻译： 根据美国专利No.5,657,897的方法制备的三聚氰胺水溶液。 在亚硫酸盐和酸性pH下通过连续缩合亚硫酸盐，三聚氰胺和甲醛的水溶液并随后的中和在加入亚硫酸盐之前通过三聚氰胺和甲醛的初步缩合并通过在pH下回流最终的缩合混合物来稳定 8.5小时以上。 用稳定的树脂溶液制备的混凝土混合物更快地固化。
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