脲醛树脂固化体系对树脂固化特性的影响

采用不同固化体系,对6种脲醛树脂的pH值、粘度、固化时间、适用期的变化情况进行研究的结果表明,一元固化体系中,以过硫酸铵为固化剂的树脂,pH值下降速度最快,固化时间短,适用期长,能满足上光工艺的要求.二元固化体系中,氯化铵与过硫酸铵组成的固化体系,树脂的pH值下降速度最快,固化时间短,适用期长,但不能满足上光工艺的要求.三元固化体系中,氯化铵、过硫酸铵与甲酸组成的固化体系固化速度稍快一些,适用期相对较短,不能满足上光工艺的要求.

Effect of UF Resins Curing System on Resins Curing Character

pH value, viscosity, curing time and the changes in the applicable period of six kinds of UF resins in different curing systems were studied. The results showed that the descent speed of pH value is the most quickly for ammonium persulfate that in one - component curing system, and the curing time was short. But the applicable period was long , fitting the demand of polishing. In binary curing system of ammonium persulfate and ammonium chloride , the curing time was very short, and pH value droped quickly, the applicable period was long . But not fitting the demand of polishing . In ternary curing system of ammonium chloride, ammonium persulfate and methanoic acid , the speed of curing is more quick , but the applicable period was shorter , not fitting the demand of polishing .