By using headspace gas chromatography, the ASTM D4443 test technique includes the detection of residual vinyl chloride monomer content in the PPB Range in vinyl chloride homo- and copolymers. Vinyl chloride-containing polymers are widely used to package a variety of materials, including foods.
The ASTM D4443 test technique can be used to determine the residual vinyl chloride monomer (RVM) content of vinyl chloride homopolymers and copolymers down to a concentration of 5 ppb. This test method can be used with any polymer that can be dissolved in a suitable solvent, such as resin, compound, film, bottle walls, and so on. The residual vinyl chloride monomer content in vinyl chloride-containing polymers is important to plastic manufacturers, food packers, government agencies, and others.
For ASTM D4443, samples of vinyl chloride-containing polymers are dissolved in a suitable solvent in a closed system. At a high temperature, the polymer solution and headspace are equilibrated. The vinyl chloride monomer is isolated using aliquots of headspace gas injected into a gas chromatograph. One of several proposed detectors is used to measure the reaction of vinyl chloride monomer. Vinyl chloride monomer in nitrogen gas standards, standard solutions having known amounts of vinyl chloride monomer, or a method of standard addition have all been used for calibration.
For ASTM D4443 test procedure, a neat and clean vinyl chloride monomer is used as a test specimen.
The vinyl chloride monomer (VCM) content is reported in parts per billion.