Coating technology: Determination of VOC content in coating by gas chromatography

It is suggested that gas chromatography is mainly to use the differences of boiling point, polarity and adsorption properties of substances to achieve the separation of paint mixture In the determination of VOC in low coating by gas chromatography, qualitative analysis can be carried out according to the retention value or quantitative analysis can be carried out by peak area The qualitative analysis of gas chromatography can be made by using the known pure substance control, relative retention value, retention index and other literature data, and can also be made by combining with other instruments Quantitative analysis of VOC content in coatings by gas chromatography, usually by peak area quantitative method Shenyang steel structure fireproof coating construction expert punde Building Fire Engineering Co., Ltd Recommended introduction: since its establishment, Shenyang punde Construction Fire Engineering Co., Ltd has cultivated a group of professional construction teams with excellent equipment, rich experience and serious responsibility with advanced and scientific management methods and strict engineering quality assurance and after-sales service system It has undertaken a number of fire system installation projects, which has been praised by customers Every idea and special requirement of you will be fully considered by us and fully realized in the construction technology, which will become the cornerstone of our successful long-term development We are looking forward to your invitation, to provide you with quality services and high-quality technical support! All construction coatings have passed ISO9001 Paint Home News: gas chromatography mainly uses the differences of boiling point, polarity and adsorption properties of substances to achieve the separation of paint mixture In the determination of VOC in low coating by gas chromatography, qualitative analysis can be carried out according to the retention value or quantitative analysis can be carried out by peak area The qualitative analysis of gas chromatography can be made by using the known pure substance control, relative retention value, retention index and other literature data, and can also be made by combining with other instruments The quantitative analysis of VOC content in coatings by gas chromatography usually uses peak area quantitative method The commonly used quantitative methods are: (1) external standard method (standard curve method), which has the advantages of simple operation, convenient calculation and high requirements for the stability of injection technology and chromatographic conditions; (2) internal standard method is to add a certain amount of pure substance as internal standard into accurately weighed samples, and calculate the content of components to be measured according to the quality of internal standard and sample and the peak area on the chromatogram The advantage of internal standard method is that it is quantitative and accurate, the operation conditions do not need to be strictly controlled, and the injection quantity does not need to be very accurate The disadvantage is that the sample and internal standard should be accurately weighed each time they are analyzed; (3) the advantage of normalization method is that the analysis results are independent of the accuracy of the injection, and the change of operation conditions has little impact on the results Normalization method requires all components in the sample to peak, and the correction factor of each component is known or measured However, the sample in coating analysis is relatively complex, and there may be unrecognized impurity peaks in the solvent, so it is not suitable for coating analysis; (4) The standard addition method (also known as peak area increasing technology) is to add pure components to be tested for sample analysis under the condition that the sample quantity, gas phase temperature, gas phase operation parameters are absolutely the same The content of the components to be measured in the original sample can be calculated by the increase of the peak area of the sample caused by the addition of the substance to be measured It should be noted that the addition of the substance to be tested can not change the matrix, otherwise it will affect the activity coefficient of the component to be tested, destroy its quantitative relationship, and get the wrong quantitative results The sample preparation process of standard addition method is similar to that of internal standard method, but the calculation principle is completely from external standard method The quantitative accuracy of standard addition method should be between internal standard method and external standard method For the complex multi-component VOC system in emulsion paint, the VOC in emulsion paint is divided into two parts: low boiling point VOC component and high boiling point VOC component The methods of qualitative and quantitative analysis are different Home of coatings is specialized in coatings, diatom mud, paint coating, coating technology, fire retardant coating news and coating, diatom mud, paint coating, coating technology, fire retardant coating decoration knowledge and decoration renderings,