双氰胺甲醛缩聚物絮凝剂的制备

Preparation of Dicyandiamide-formaldehyde Flocculant

通过实验研究了双氰胺甲醛缩聚物絮凝剂合成最佳条件,分析了双氰胺甲醛缩聚物合成过程中的强放热现象并提出解决方法。研究了物料用量、温度及时间等因素对双氰胺甲醛缩聚反应的影响,得到双氰胺甲醛缩聚物絮凝剂最佳的制备工艺,即双氰胺、甲醛和氯化铵摩尔比为1:2.1:0.9投料,反应温度60℃,反应时间1.5 h。影响升温放热的因素是催化剂氯化铵而不是甲醛,分批加入氯化铵即可很好地控制反应温度。

In this paper, the optimum synthesis condition of dicyandiamide-formaldehyde condensation copolymer was explored, and the exothermic phenomenon in a short time was analyzed, the solution was put forward. Effect of material dosage, reaction temperature and time on the condensation polymerization was investigated, the best synthesis conditions were determined as follows： the mole ratio of dicyandiamide, formaldehyde and ammonium chloride 1：2.1：0.9, the reaction temperature 60℃ and the reaction time 1.5 h. The results show that the factor that affect the heat release and temperature rising is the catalyst instead of the formaldehyde, so the reaction temperature can be controlled by adding ammonium chloride in batches.