Vycor Porous Glass (Thirsty Glass) as a Reaction Medium for Optical Waveguide Based Chemical Vapor Detectors

Abstract

Vycor Porous Glass (Thirsty Glass) has been studied as a reaction medium for several model chemical vapor detection reactions. It was also compared with Celgard 2400 microporous propylene film as a reaction medium. Using Thirsty Glass as the reaction support for the detector reagent 2,6-dichloroquinone-4-cnloroimide, 1-butanethiol was detected at concentrations as low as 0.1 ppm. With either 4,4′-bis(diethytamino)benzophenone oxime or 1,3-diisonitrosoacetone as the detector reagent, methanesulfonyl chloride was detected at concentrations in air as low as 1 ppm. When 4-(p-nitrobenzyl)pyridine was the detector reagent, high detection sensitivities for 2-chloroethylethylsulfide and dimethylsulfate were achieved only when a two-step test procedure was used.

Key Words:

• VYCOR porous glass
• 1,3-diisonitrosoacetone
• 4,4-bis-(diethylarpino)benzophenone oxime
• 2,6-di-chloroquinone-4-chloroimide
• 4-(p-nitrobenzyl)-pyridine
• methanesulfonyl chloride
• 1-butanethioI
• 2-chloroethylethyIsulfide
• dimethylsulfate