COLORIMETRIC POLYMER FILM SENSORS FOR DISSOLVED CARBON-DIOXIDE

Andrew Mills, Q. Chang

Research output: Contribution to journalArticlepeer-review

27 Citations (Scopus)

Abstract

Plasticized and unplasticized polymer colorimetric film sensors for gaseous CO2, containing the dye m-cresol purple, are tested as sensors for dissolved CO2. The plasticized polymer m-cresol purple film sensor develops a measurable degree of opacity when exposed to aqueous solution, especially in neutral, compared with alkaline, solution. However, it is shown that a presoaked, fogged plasticized polymer m-cresol purple film does function as a quantitative sensor for dissolved CO2 over the range 0-4% CO2. An unplasticized polymer m-cresol purple film remains largely dear upon exposure to aqueous solution and also functions as a quantitative sensor for dissolved CO2 over the range 0-4% CO2. However, in both types of films the dye interacts with electrolytes present in solution; invariably the dye appears to be converted from its initial deprotonated form (blue) to its protonated form (yellow) and the rate of this process appears to increase with increasing ionic strength, anionic charge and decreasing pH. The 90% response and recovery times for an unplasticized film are determined as 19 s(CO2:0-->5%) and 21 s (CO2:5-->3.6%), respectively.
Original languageEnglish
Pages (from-to)83-89
Number of pages7
JournalSENSORS AND ACTUATORS B-CHEMICAL
Volume21
Publication statusPublished - 1994

Fingerprint

Dive into the research topics of 'COLORIMETRIC POLYMER FILM SENSORS FOR DISSOLVED CARBON-DIOXIDE'. Together they form a unique fingerprint.

Cite this