Abstract
Vapor detectors formed from composites of conductors and insulating organic polymers have been tailored to produce increased sensitivity toward specific classes of analyte vapors. Upon exposure to acetic acid at 1% of its vapor pressure, detectors consisting of linear poly(ethylenimine) (1-PEI)-carbon black composites showed an ∼103 increase in signal/noise relative to the performance of typical insulating organic polymer-carbon black composite vapor detectors. Compositional diversity in an array of such vapor detectors was obtained by varying the degree of plasticization of the 1-PEI films. The resulting vapor detector array produced sensitive detection of, and robust discrimination between, various volatile organic acids and relatively little response from nonacidic organic vapors or from water vapor. Measurements of the mass uptake, thickness change, and electrical conductivity of such composites indicate that swelling of the polymer film, and thus its normalized resistance response, is beyond that expected by mass uptake alone upon exposure to acetic acid vapor. This additional thickness increase is attributed to charge-induced polymer swelling occurring from polymer-analyte interactions. Electrical percolation also plays a significant role in producing the large increase in normalized resistance response of these composites upon exposure to acetic acid vapor.
| Original language | English |
|---|---|
| Pages (from-to) | 1748-1753 |
| Number of pages | 6 |
| Journal | Analytical Chemistry |
| Volume | 75 |
| Issue number | 7 |
| DOIs | |
| Publication status | Published - Apr 1 2003 |
Fingerprint
ASJC Scopus subject areas
- Analytical Chemistry
Cite this
Enhanced sensitivity to and classification of volatile carboxylic acids using arrays of linear poly(ethylenimine)-carbon black composite vapor detectors. / Tillman, Eric S.; Koscho, Michael E.; Grubbs, Robert H.; Lewis, Nathan S.
In: Analytical Chemistry, Vol. 75, No. 7, 01.04.2003, p. 1748-1753.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Enhanced sensitivity to and classification of volatile carboxylic acids using arrays of linear poly(ethylenimine)-carbon black composite vapor detectors
AU - Tillman, Eric S.
AU - Koscho, Michael E.
AU - Grubbs, Robert H.
AU - Lewis, Nathan S
PY - 2003/4/1
Y1 - 2003/4/1
N2 - Vapor detectors formed from composites of conductors and insulating organic polymers have been tailored to produce increased sensitivity toward specific classes of analyte vapors. Upon exposure to acetic acid at 1% of its vapor pressure, detectors consisting of linear poly(ethylenimine) (1-PEI)-carbon black composites showed an ∼103 increase in signal/noise relative to the performance of typical insulating organic polymer-carbon black composite vapor detectors. Compositional diversity in an array of such vapor detectors was obtained by varying the degree of plasticization of the 1-PEI films. The resulting vapor detector array produced sensitive detection of, and robust discrimination between, various volatile organic acids and relatively little response from nonacidic organic vapors or from water vapor. Measurements of the mass uptake, thickness change, and electrical conductivity of such composites indicate that swelling of the polymer film, and thus its normalized resistance response, is beyond that expected by mass uptake alone upon exposure to acetic acid vapor. This additional thickness increase is attributed to charge-induced polymer swelling occurring from polymer-analyte interactions. Electrical percolation also plays a significant role in producing the large increase in normalized resistance response of these composites upon exposure to acetic acid vapor.
AB - Vapor detectors formed from composites of conductors and insulating organic polymers have been tailored to produce increased sensitivity toward specific classes of analyte vapors. Upon exposure to acetic acid at 1% of its vapor pressure, detectors consisting of linear poly(ethylenimine) (1-PEI)-carbon black composites showed an ∼103 increase in signal/noise relative to the performance of typical insulating organic polymer-carbon black composite vapor detectors. Compositional diversity in an array of such vapor detectors was obtained by varying the degree of plasticization of the 1-PEI films. The resulting vapor detector array produced sensitive detection of, and robust discrimination between, various volatile organic acids and relatively little response from nonacidic organic vapors or from water vapor. Measurements of the mass uptake, thickness change, and electrical conductivity of such composites indicate that swelling of the polymer film, and thus its normalized resistance response, is beyond that expected by mass uptake alone upon exposure to acetic acid vapor. This additional thickness increase is attributed to charge-induced polymer swelling occurring from polymer-analyte interactions. Electrical percolation also plays a significant role in producing the large increase in normalized resistance response of these composites upon exposure to acetic acid vapor.
UR - http://www.scopus.com/inward/record.url?scp=0037374833&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0037374833&partnerID=8YFLogxK
U2 - 10.1021/ac020412l
DO - 10.1021/ac020412l
M3 - Article
VL - 75
SP - 1748
EP - 1753
JO - Analytical Chemistry
JF - Analytical Chemistry
SN - 0003-2700
IS - 7
ER -