摘要
异氰酸酯基(NCO基)含量是聚氨酯工业中重要的指标,关系到异氰酸酯预聚体中的反应活性,直接影响聚氨酯产品性能。文章应用Mettler Toledo T90电位滴定仪进行等当点滴定,以ASTM D5155—14 Standard Test Methods for Polyurethane Raw Materials:Determination of the Isocyanate Content of Aromatic Isocyanates中方法A为指导,对比GB/T 12009.4—2016《塑料聚氨酯生产用芳香族异氰酸酯第4部分:异氰酸根含量的测定》(A)的优势与不同,筛选溶剂,最终确定了样品前处理方法与滴定参数。改进的滴定方法适合不同体系异氰酸酯中NCO基含量测定,满足精度(绝对误差<0.2%)要求同时降低废液产量。自动进样盘的配合使用降低了滴定过程耗时,是一种自动化程度高的化学分析法。
The concentration ofisocyanic acid(NCO)is an important index in polyurethane industry.It relates to the reactivity ofisocyanate prepolymer and directly affects the properties of polyurethane products.Mettler Toledo T90 potentiometric titrator was used for isocyanate EQP titration.Improved potentiometric titration method was established by using the ASTM D5155—14(Standard Test Methods for Polyurethane Raw Materials:Determination of the Isocyanate Content of Aromatic Isocyanates,Method A)as the guidance,compared with national standard method GB/T 12009.4—2016.The titrimetric solution,sample pretreatment method and titration parameter was established.The improved titration method is applied for the determination of NCO content in different polyurethane systems.It satisfies the requirement of accuracy(absolute error<0.2%)and reduces the output of waste liquid.The using of automatic sampling tray reduces the time-consuming of titration process and provides a standard value for establishing IR method.
作者
孔德婷
刘聪云
马琳鸽
张栋
李永龙
KONG De-ting;LIU Cong-yun;MA Lin-ge;ZHANG Dong;LI Yong-long(National Institute of Clean-and-Low-Carbon Energy,CHN Energy,Beijing 102209,China)
出处
《化工管理》
2021年第34期52-53,73,共3页
Chemical Engineering Management
关键词
电位滴定
等当点
异氰酸酯
NCO基
potentiometric titration
equivalence point
isocyanate
NCO group
