Aging of rigid polyurethane foams: Thermal conductivity of N-2 and cyclopentane gas mixtures

authors	Marrucho, IM; Santos, F; Oliveira, NS; Dohrn, R
nationality	International
journal	JOURNAL OF CELLULAR PLASTICS
author keywords	blowing agents; nitrogen; cyclopentane; thermal conductivity; transient hot wire method
keywords	HOT-WIRE METHOD; R365MFC
abstract	The thermal conductivity of three mixtures of nitrogen and cyclopentane is measured using a transient hot wire method, at temperatures between 315.14 and 395.89 K, and pressures up to 0.53 MPa. These mixtures are important in the evaluation of the evolution of the thermal insulation capacity of closed-cell polyurethane foams considering their aging during the respective applications' total life time. The experimental thermal conductivity data are correlated with the Wassiljewa mixing rules as modified by Mason and Saxena, and predicted using extended corresponding states theory (ECST), with an average absolute deviation of 1.1 and 8.9%, respectively. The increase of the nitrogen fraction in cyclopentane-nitrogen mixtures leads to higher thermal conductivity values than has been predicted by ECST using only pure component thermal conductivity data for all measurements.
publisher	SAGE PUBLICATIONS LTD
issn	0021-955X
year published	2005
volume	41
issue	3
beginning page	207
ending page	224
digital object identifier (doi)	10.1177/0021955X05053520
web of science category	Chemistry, Applied; Polymer Science
subject category	Chemistry; Polymer Science
unique article identifier	WOS:000238078400001