Determination of Volatile Organic Compounds in Water-based Paints and Varnishes Using GC-MS

Significance of the Topic

Water based paint is widely used due to rapid drying ease of cleaning and reduced odor compared to solvent based systems. Volatile organic compounds are responsible for paint odor pose health risks for users and workers and impact environment. Regulatory trends and consumer demand drive development of low VOC and zero VOC formulations highlighting need for accurate quantitation in compliance and quality control.

Objectives and Study Overview

The study aims to establish a robust method for quantitation of 35 common volatile organic compounds in water based paints and varnishes via gas chromatography mass spectrometry following ISO 11890-2 guidelines. Two commercial paint samples for indoor and outdoor use were tested to demonstrate method performance and determine total VOC content.

Methodology and Instrumentation

A single quadrupole GC MS system was used. Analytical conditions included injection at 250 deg C split ratio 50 column temperature programming from 50 to 280 deg C and scan mode acquisition from 30 to 400 amu. Sample preparation applied a modified ISO 11890-2 workflow comprising paint weighing internal standard addition solvent extraction sonication centrifugation and filtration. Calibration standards from 10 to 2000 ppm were prepared in acetonitrile using diethyl adipate as boiling point marker. Instrumentation included:

• Shimadzu GCMS QP2010 Ultra gas chromatograph mass spectrometer
• AOC 5000 Plus auto injector
• Rxi 624 Sil MS column 30 m 0.25 mm 1.4 microm
• Helium carrier gas 99.9997 percent

Main Results and Discussion

The method achieved separation of 35 volatile organic compounds with linear calibration curves R2 above 0.997 and repeatability percent relative standard deviation below 5 percent for most analytes. Mass spectral analysis resolved overlapping peaks except for m xylenes and p xylenes reported together as total xylenes. Indoor and outdoor paint samples contained 1.05 percent and 2.58 percent VOC respectively. Peaks eluting after the boiling point marker were excluded from VOC calculation in line with ISO 11890-2. An uncalibrated compound identified as toluenol was quantified using assumed response factor of one.

Benefits and Practical Applications

The developed GC MS method provides:

• Comprehensive quantitation of a wide range of solvents in water based paints
• High sensitivity and precision suitable for regulatory compliance
• Efficient sample preparation workflow compatible with quality control
• Capability to detect unknown or emerging volatile compounds

Future Trends and Opportunities

Advances in low thermal mass chromatography and high resolution mass spectrometry will further reduce analysis time and improve detection limits. Development of automated data processing and multivariate screening may enable rapid compound identification and routine monitoring. Emerging regulations in Asia and other regions will increase demand for validated methods for VOC assessment in coatings and related products.

Conclusion

A reliable GC MS procedure was established for determination of 35 volatile organic compounds in water based paints and varnishes. The method achieves robust linear calibration good repeatability and complies with international guidelines. It is suitable for both routine quality control and regulatory testing.

Reference

1. Future is water based Standox retrieved 07 Mar 2014
2. Wieslander Norback Edling Occupational and Environmental Medicine 1994 51 181-186
3. Wieslander Norback Bjornsson International Archives of Occupational and Environmental Health 1997 69 115-124
4. ISO 11890-2 2013 Paints and varnishes Determination of volatile organic compound content Part 2 Gas chromatographic method