The Impact of Atmospheric Parameters on the Dielectric Permittivity Values of SikaBlock®-M150 and Other Rigid Polyurethane Foams Measured with a Capacitive One-Side Access Sensor
Sensors 2022
Sergejs Gaidukovs, Ilze Beverte, Jānis Andersons, Vilisa Skruls

A shortage of research on the impact of atmospheric parameters on the measured dielectric permittivity values of rigid polyurethane (PU) foams was identified. Therefore, the impact of temperature, pressure, and relative humidity of air in the test room on the measured values of dielectric permittivity of rigid PU foams of different densities as well as monolithic polyurethane was investigated in a year-long experimental research study with a capacitive one-side access sensor. It was shown that relative humidity has the highest correlation with the dielectric permittivity values of rigid PU materials. The detected values of parameters were linked to the water vapour mass in ambient air and its correlation with permittivity of the investigated materials was determined. The warm-up drift and warm-up time of the spectrometer were estimated experimentally. A novel methodology was demonstrated to determine the true permittivity spectrum of rigid PU foams without any involvement of the environmental chamber, desiccators, or saturated salt/water solutions. A relative increase in the measured dielectric permittivity value was estimated numerically for the entire density range of rigid PU foams, i.e., 33–1280 kg/m3 (including monolithic PU).


Keywords
polyurethane foams; capacitive sensor; one-side access; dielectric permittivity; measurements; relative humidity; temperature; absorption; warm-up drift
DOI
10.3390/s22207859
Hyperlink
https://www.mdpi.com/1424-8220/22/20/7859

Gaidukovs, S., Beverte, I., Andersons, J., Skruls, V. The Impact of Atmospheric Parameters on the Dielectric Permittivity Values of SikaBlock®-M150 and Other Rigid Polyurethane Foams Measured with a Capacitive One-Side Access Sensor. Sensors, 2022, Vol. 22, No. 20, pp.7859-7859. ISSN 1424-8220. Available from: doi:10.3390/s22207859

Publication language
English (en)
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