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Title: Quartz Crystal Microbalance: A tool for analyzing loss of volatile compounds, gas sorption, and curing kinetics

Abstract

Los Alamos National Laboratory (LANL) has recently procured a quartz crystal microbalance (QCM). Current popular uses are biological sensors, surface chemistry, and vapor detection. LANL has projects related to analyzing curing kinetics, measuring gas sorption on polymers, and analyzing the loss of volatile compounds in polymer materials. The QCM has yet to be employed; however, this review will cover the use of the QCM in these applications and its potential.

Authors:
 [1]
  1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1351175
Report Number(s):
LA-UR-17-22231
DOE Contract Number:
AC52-06NA25396
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; Material Science

Citation Formats

Bajric, Sendin. Quartz Crystal Microbalance: A tool for analyzing loss of volatile compounds, gas sorption, and curing kinetics. United States: N. p., 2017. Web. doi:10.2172/1351175.
Bajric, Sendin. Quartz Crystal Microbalance: A tool for analyzing loss of volatile compounds, gas sorption, and curing kinetics. United States. doi:10.2172/1351175.
Bajric, Sendin. Thu . "Quartz Crystal Microbalance: A tool for analyzing loss of volatile compounds, gas sorption, and curing kinetics". United States. doi:10.2172/1351175. https://www.osti.gov/servlets/purl/1351175.
@article{osti_1351175,
title = {Quartz Crystal Microbalance: A tool for analyzing loss of volatile compounds, gas sorption, and curing kinetics},
author = {Bajric, Sendin},
abstractNote = {Los Alamos National Laboratory (LANL) has recently procured a quartz crystal microbalance (QCM). Current popular uses are biological sensors, surface chemistry, and vapor detection. LANL has projects related to analyzing curing kinetics, measuring gas sorption on polymers, and analyzing the loss of volatile compounds in polymer materials. The QCM has yet to be employed; however, this review will cover the use of the QCM in these applications and its potential.},
doi = {10.2172/1351175},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Thu Mar 16 00:00:00 EDT 2017},
month = {Thu Mar 16 00:00:00 EDT 2017}
}

Technical Report:

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  • Quartz crystal microbalances (QCMs) are piezoelectric thickness-shear-mode resonators where the resonant frequency has long been known to vary linearly with the mass of rigid layers on the surface when the device is in contact with air. This reports summarizes the results from a Laboratory Directed Research and Development effort to use an array of QCMs to measure and identify volatile organic compounds (VOCs) in water solutions. A total of nine polymer-coated QCMs were tested with varying concentrations of twelve VOCs while frequency and damping voltage were measured. Results from these experiments were analyzed using a Sandia-developed pattern recognition technique calledmore » visually empirical region of influence (VERI) developed at Sandia. The VERI analyses of data with up to 16% and 50% sensitivity drifts were carried out on an array with six signals obtained from five sensors. The results indicate that better than 98% and 88% correct chemical recognition is maintained for the 16% and 50% drifts, respectively. These results indicate a good degree of robustness for these sensor films.« less
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  • This CRADA continued the commercialization of the dual quartz crystal microbalance (DQCM) begun in 1994 as a Staff Exchange (CRADA PNL-070). The completion of PNL-070 resulted in NISI possessing the technology for the DQCM chemical sensor precursor, that is, the device that will sensitively detect mass changes and which becomes a chemical sensor with the addition of a chemically sensitive film. NISI also owned prototype DQCM probes and accompanying data measuring organics in water to show DOE/Westinghouse/Bechtel. The follow-on CRADA supported the instrumentation and manufacturing development at a low level but primarily provided funds for developing the active films. Asmore » a result of this research, NISI received PNNL specifications for particular polymer films, and characterizations of the chemical response of DQCM probes prepared with these films. Construction and performance of a dual quartz crystal microbalance is described.« less
  • We are using a Qpod quartz crystal microbalance (manufactured by Inficon) for use as a low-volume non-volatile residue analysis tool. Inficon has agreed to help troubleshoot some of our measurements and are requesting to view some sample data, which are attached. The basic principle of an NVR analysis is to evaporate a known volume of solvent, and weigh the remaining residue to determine the purity of the solvent. A typical NVR analysis uses 60 g of solvent and can measure residue with an accuracy of +/- 0.01 mg. The detection limit is thus (0.01 mg)/(60 g) = 0.17 ppm. Wemore » are attempting to use a quartz crystal microbalance (QCM) to make a similar measurement. The attached data show the response of the QCM as a 5-20 mg drop of solvent evaporates on its surface. The change in mass registered by the QCM after the drop evaporates is the residue that deposits on the crystal. On some measurements, the change in mass in less than zero, which is aphysical since the drop will leave behind {>=}0 mass of residue. The vendor, Inficon, has agreed to look at these data as a means to help troubleshoot the cause.« less