Detection and Indentification of Volatiles in Oil Base Paintsby Headspace GC with On Column Cryo-Trapping


John J. Manura, Scientific Instrument Services, 1027 Old York Rd, Ringoes, NJ 08551

Poster Number - 381P

Large headspace gas volumes can be introduced into a capillary GC column for subsequent analysis. This is accomplished via the use of a small on column cryo-trap which permits the concentration and focusing of volatiles at the head of the GC capillary column.

One gram to 0.1 gram sample sizes of oil base paints were weighed into a 10 mL headspace sample vial and sealed. The vials were heated to 90 °C and agitated for 10 minutes. Headspace volumes from 0.1 to 5.0 mL were injected into the GC injection port slowly (1.5 mL/min) utilizing the LEAP Headspace autosampler and the volatiles cryo-focused at the front of the GC column at -100 °C using the GC Cryo-Trap. After injection was complete the injection port was flushed of all volatiles, the cryo-trap was heated to 200 °C to release the trapped organics, and the GC oven was temperature programmed to elute the organics. The resulting peaks were identified via a H.P. 5989A mass spectrometer. A large number of oil base paints from various manufacturers were studied to demonstrate the versatility of the technique for the identification of the volatiles in oil base paints and to show the reproducibility of the technique for use as a quality control technique. Each of the paints studied produced characteristic fingerprints of more than 50 peaks. The technique has proven useful for the identification of volatile organics in paints, for use as a quality control technique and for the comparison of paints from different manufacturers.