气相色谱法检测水性内墙涂料中水分含量

Determination of Water Content in Waterborne Interior Wall Coatings by Gas Chromatography

通过改善萃取试剂、优化相对校正因子、超声萃取时间、进样体积等影响因素,建立简便、准确的气相色谱法检测水性内墙涂料中水分含量的方法。实验方法最优的分析条件为:0.2 g样品加入2 mL异丙醇(0.1 g/mL)DMF内标溶液,恒温23℃超声萃取10 min,恒温23℃离心5 min,1.0μL上清液进气相色谱分析。采用内标法,应用校正曲线计算内墙涂料中水分含量。水分含量校准曲线方程为Y=2.43X+0.049,相关系数R2=0.999 8。相对标准偏差(RSD)为0.22%~0.68%(n=6),回收率为98%~108%。实验方法提高了萃取效率,缩短了分析时间,减少了实验误差,具有良好的重现性和准确性。

A simple and accurate method for the determination of water content in waterborne interior wall coatings was established by improving the extraction reagents, optimizing relative correction factors, ultrasonic extraction time, and injection volume. The optimal analysis conditions are: adding 2 mL of isopropanol(0.1 g/mL) DMF internal standard solution to a 0.2 g sample, ultrasonic extraction at 23 °C for 10 minutes, centrifugation at 23 °C for 5 minutes and 1.0 μL of supernatant analyzed by gas chromatography. Using the internal standard method, the calibration curve was used to calculate the water content of the interior wall coatings. The calibration curve equation is Y=2.43 X+0.049, and correlation coefficient R^2=0.999 8. The relative standard deviation(RSD) was 0.22%~0.68%(n=6), and the recovery was 98%~108%. The experimental method improves the extraction efficiency, shortens the analysis time, reduces the experimental error, and has good reproducibility and accuracy.