The conversion rate of 4-hydroxymethylcoumarin modified aliphatic isocyanates was tested using UV spectrophotometer,with linear range of 0-25 mg/L and R2=0.999 5 within this range.The detection limit of the method was 0.14 mg/L.At three spiking levels of low,high,and medium,the average recovery rate was 95.0%,with relative standard deviation of 1.4%,indicating that this method was accurate and simple.
维普
万方数据