Method for simultaneously detecting volatile organic compounds in paint

Abstract

The invention relates to the field of analysis and detection, in particular to a method for simultaneously detecting volatile organic compounds in paint. In sampling operation, due to improvement of acomponent mixing operation process specified by a national standard method, uncertainty in sampling operation due to factors including nonuniform volatile speed, difficulty in mixing effect determination and the like in mixing of all components of paint is lowered. By sampling through a special quantitative capillary tube for thin-layer chromatographic spotting, simplicity, convenience and feasibility are achieved, and damaging of airtightness of a head-space bottle cap is avoided by placement of the capillary before sealing. Introduction quantity of samples in a head-space bottle is small due to almost complete volatilization, and inertia can be well kept under the condition that reusing of the head-space bottle is benefited. By gas sample introduction, introduction of nonvolatile matters into a gas chromatography system can be avoided, and prolonging a maintenance period of the chromatography system and service lives of consumables is benefited. A mass spectrometer is capable of effectively separating and recognizing methyl alcohol, benzenes, halohydrocarbon and the like from other volatile components in samples and meets quantitative detection requirements.

Description

technical field [0001] The invention relates to the field of analysis and detection, in particular to a method for simultaneously detecting volatile organic compounds in coatings. Background technique [0002] The current national standard GB18581-2009 "Limits of Hazardous Substances in Solvent-based Wood Coatings for Interior Decoration Materials" stipulates gas chromatography-related detection methods for the content of methanol, benzene series, and halogenated hydrocarbons in solvent-based wood coatings. The method adopts the internal standard method for methanol, benzene series and halogenated hydrocarbon content, but the practice of actual inspection shows that such detection method has the following deficiencies: 1. Gas chromatography detection lacks qualitative means of target objects except retention time, and also It often causes false positives or falsely increased test results; 2. Both halogenated hydrocarbons and benzene series are organic compounds with low boil...

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Problems solved by technology

The method adopts the internal standard method for methanol, benzene series and halogenated hydrocarbon content, but the practice of actual inspection shows that such detection method has the following deficiencies: 1. Gas chromatography detection lacks qualitative means of target objects except retention time, and also It often causes false positives or falsely increased test results; 2. Both halogenated hydrocarbons and benzene series are organic compounds with low boiling points. The test of the two items also needs to be separated by a relatively long time and low column temperature program. In principle, There is a possibility of combined detection; 3. Liquid sampling after paint dilution and dissolution will result in more non-volatiles remaining at the injection port, these non-volatiles are mainly resins and metal pigments, etc. The test causes adsorption, which leads to poor repeatability of sample detection; 4. The method of separate detection of different targets stipulated in the current standard greatly reduces the efficiency of detection work and increases the repeatability of operation. Reagent consumption does not conform to the development trend of the testing industry for environmental protection and energy saving

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