Document OzJkN0x0JBzn5zozp1j3zBQy1

r> .t U.S. DEPARTMENT OF LABOR Occupations! S.ifeiv utul Health AJmimsmttion WASHINGTON',' D.C. 20:10 MEMORANDUM FOR RECIPIENTS OF THE DRAFT ENVIRONMENTAL IMPACT STATEMENT ON PROPOSED REGULATION VINYL CHLORIDE This is to inform you that the final date for submission of comments on the draft environmental impact statement on vinyl chloride, previously announced as July 17, 1974, has been extended to August 5, 1974. The increased time period for public comment allows 45 days from the Council on Environmental Quality's notice of receipt of the draft document in the Federal Register. Comments should be sent to David R. Bell, Office of Standards Development, Room 500, 1726 M Street, N-V?. , Washington, D.C. 20210, by August 5, 1974 to assure their consideration. Any inconvenience caused by the change in comment Daniel P. Boyd, Ph.D. Director Office of Standards Development RSV 0003068 DETEfLMixatioxOF residual vinyl chloride MONOMER IN VINYL RESINS PURPOSE A procedure for determining the amount of residual vinyl chloride present in vinyl resins is described. The resin is dissolved in a solvent and the vinyl chloride analyzed using a gas chroma tographic technique. The method is applicable for use with poly (vinyl chloride), vinyl chloride-vinyl acetate copolymers and other vinyl resins in which there are no volatiles which interfere in the determination. EQUIPMENT AND REAGENTS Gas Chromatograph, Hewlett-Packard (F and M) Model'5750 or equivalent, equipped with a hydrogen flame ionisation detector. Tetrahydrofuran, reagent grade. Balance with accuracy to 0.10 gram. SAMPLE PREPARATION Prepare the sample for chromatograph injection by dissolving the test resin in tetrahydrofuran (THF). Weigh 9 grams of TKF into a suitable vial. Add 1 gram of the resin to be tested to the THF. Resin addition should be made as quickly as possible. Cap the bottle and place it on a can-roller to attain complete solution. When complete solution has occurred, the sample is ready for injection into the chromatograph. INSTRUMENT PARAMETERS Instrument Hewlett-Packard(F/M) Model 5750 (or equivalent) equipped with hydrogen flame ionization detector. Column 6-ft by 1/8-in. stainless steel tubing packed with Chromosorb 102, 60/S0 mesh. Temperatures: Column Inj ector Detector 100C for 4 minutes, manually to 250C 100C (maximum) 300C (flame ionization) increased Sample Size 4 microliters Flows: Helium Carrier Hydrogen AH v Gas 25 cc/minute 20 psi at cylinder head an at. cvlindor head RSV 0003869 2- - Elution Tines Vinyl Chloride Tetrahydrofuran 2.8 minutes 6.3 minutes 5 CALIBRATION Prepare solution mixtures of varying amounts of vinyl chloride in tetrahydrofuran to cover the expected range of concentration. Obtain from the chromatograph scan the area per cent of vinyl chloride for each sample of known monomer content. Prepare a chart plotting the area per cent vinyl chloride versus the known weight per cent vinyl chloride to establish the relative detector response of the vinyl chloride with respect to tetrahydrofuran. 6 CALCULATION Determine the area per cent vinyl chloride from the chromatograph scan for the resin solution to be characterized. Multiply this figure by 10, which converts the data to area per cent vinyl chloride based on resin weight. Using the chart developed with the calibration samples, read off the corresponding weight per cent of vinyl chloride. RSV 0003870 TYPICAL CALIBRATION CURVE Residual Vinyl Chloride Monomer in Vinyl Resin Area Percent Conversion to -Weight -Percent...,, 0.0050 0.0040 0.0030 AREA PERCENT 0.0020 0.0010 WEIGHT PERCENT RSV 0003871 FIGURE 1 SYNTHETIC SAMPLE OF 1 PPM VINYL CHLORIDE IN THE SOLVENT (Sample Volume = 2 Microliters) i a r tc iiu a i.i t/n T etrahydrofuran RSV 0003872 1' Kiu ivo SYNTHETIC SAMPLE OF 10 PPM VINYL CHLORIDE IK THE SOLVENT (Sample Volume - 2 Microliters) o *oi-l uo> HuB OO CH d O >o xS c rl U o o .c cj +J o E-* 104x32 > A tte n u a tio n Retention Time, Minutes KSV 0003873 TYPICAL PVC RESIN IN THE SOLVENT SCAN (Sample Volume - 4 Microliters) 104x32 c C3 U V-4 o u o >* j=: es i .A tte n u a tio n Retention Time, Minutes 8 RSV 0003874