Gas chromatography is used to test the volatile organic compound content of solvent polyurethane waterproofing coatings,and the influence of two internal standard substances,i.e.toluene and diethylene glycol dimethyl ether,on the testing results is studied.The results show that the volatile organic compound content of the coating which takes diethylene glycol dimethyl ether as an internal standard is nearly three times higher than that of the coating with toluene as an internal standard.The volatile organic compound of solvent polyurethane waterproofing coating is mainly a mixture of trimethylbenzene and tetramethylbenzene.Due to the difficulty in obtaining their calibration substances,their relative correction factors are set to 1.0 according to relevant standards.The molecular structures of toluene and diethylene glycol dimethyl ether differ greatly,resulting in significant differences in test results.Therefore,it is more reasonable to choose toluene,which has a similar molecular structure to trimethylbenzene and tetramethylbenzene,as the internal standard.
维普
万方数据