脲醛树脂微胶囊包覆红磷阻燃剂制备工艺的研究 Ⅰ.预聚物合成工艺研究

研究了脲醛树脂的预聚物通过原位聚合对红磷进行包覆的一些影响因素。实验表明影响预聚物质量的主要因素是第一阶段尿醛比(F/U)1,第二阶段尿醛比(F/U)2,反应温度和pH值。制备预聚物的最佳条件为:第一阶段尿醛比为2.3∶1(摩尔比),第二阶段尿醛比为1.3∶1(摩尔比),pH值为5.1,反应温度为75℃。制备的预聚物来包覆红磷,颜色为白色;用微胶囊红磷阻燃聚乙烯,当含量为9%时,在500℃下残余物为4.85%。

Study on preparation technology of flame retardant of red phosphorus coated by urea-formaldehyde resin Ⅰ. Synthetic condition of preformed polymer

Some conditions of depositing urea-formaldehyde resin onto the surface of red phosphorus by in-situ polymerization were studied in this paper.Experiments proved the main factors influence the quality of preformed polymer are the first ratio of formaldehyde to urea,the second ratio of formaldehyde to urea,reaction temperature and pH value. The optimum conditions of preparing preformed polymer was obtained,that is : the first step mole ratio of formaldehyde to urea is 2.3∶1, the second step mole ratio of formaldehyde to urea is 1.3∶1, pH value is 5.1 and the reacting temperature is 75℃.When PE treated by red phosphorus encapsulated by urea formaldehyde resin, the remainder is 4.85% at 500℃ when its content is 9%.