Systematic investigation of the sorption properties of polyurethane foams for organic vapors.

Anal Chem

Department of Biogeochemistry and Pollutant Dynamics, ETH Zurich, Universitätsstrasse 16, 8092 Zurich, Switzerland.

Published: June 2007

Polyurethane foams (PUFs) have long been used for the sampling of airborne organic pollutants. However, a comprehensive investigation of their sorption properties for various organic compounds is still lacking. Here we present a systematic sorption study for a diverse set of up to 100 compounds at temperatures between 15 and 95 degrees C, at various humidities, and for various types of PUFs. The results can be summarized as follows: The performance of PU-ethers is not susceptible to the humidity of the sampled air. Variability between different types of PU-ethers is small, and the compound variability in the sorption constants as well as the enthalpies of sorption can accurately be described with linear free energy relationships (LFERs) presented in the text. PU-esters revealed an inferior sorbent behavior as compared to PU-ethers: sorption was kinetically hindered and was affected by humidity. Sorption varied between different types of esters and prediction with LFERs was less accurate than for the ethers.

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http://dx.doi.org/10.1021/ac070265xDOI Listing

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