A fluorine gas monitoring system for the direct oxy‐fluorination of polyethylene sheets

Abstract

ABSTRACT:A new technique is presented to measure the concentration of fluorine in a reaction gas consisting of fluorine, nitrogen, and oxygen in a reaction chamber. The method is described as follows: The gas is directly taken from the chamber using a peristaltic pump and dissolved in a TISAB (total ionic strength adjusted buffer) solution. The concentration of fluorine ion is measured using the selected fluorine ion electrode, the output voltage of which is monitored. The concentration of the fluorine ion and the output voltage follow the Nernst relation so that the measurement of the output voltage of the system enables us to know the concentration of fluorine gas. This technique was applied to monitor the concentration of fluorine gas in the chamber in which a sheet of polyethylene nonwoven fabric was continuously oxy-fluorinated. The monitored concentration of the fluorine gas as a function of time coincided with the variation of the incorporated fluorine in the sheet measured by X-ray fluorescence (XRF) spectroscopy after the treatment. This technique can be best used for process control of the continuous oxy-fluorination of polymeric materials. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 684 -691, 2002

Atomic spectrometry update. Industrial analysis: metals, chemicals and advanced materials

“…An on-line process monitoring system for the determination of F incorporation into polyethylene sheets has been described by Kasai et al 284 The gaseous contents of a reaction chamber containing F, N and O, as well as the polyethylene sheet, were sampled via a peristaltic pump. After mixing with TISAB buffer, the F content was determined using an ion selective electrode.…”