Thermal Performance of Sprayed Polyurethane Foam Insulation with Alternative Blowing Agents

Abstract

/npsi/ctrl?lang=en http://nparc.cisti-icist.nrc-cnrc.gc.ca/npsi/ctrl?lang=fr Access and use of this website and the material on it are subject to the Terms and Conditions set forth at http://nparc.cisti-icist.nrc-cnrc.gc.ca/npsi/jsp/nparc_cp.jsp?lang=en NRC Publications Archive Archives des publications du CNRCThis publication could be one of several versions: author's original, accepted manuscript or the publisher's version. / La version de cette publication peut être l'une des suivantes : la version prépublication de l'auteur, la version acceptée du manuscrit ou la version de l'éditeur. Insulation, 14, July, pp. 43-57, 1990-07 ABSTRACT: A test methodology that uses thcrmal resistance-time curves determined on thin slices of the foam and the scaling technique to relate aging time to the specimen thickness, was applied to evaluate long-term thcrmal performancc of six polyurethane foams manufactured with the same polymer but different blowing agents. The blowing agents employed were: CFC-11 with 0, 0.5, 1.0 or 1.5% water and HCFC-123 or HCFC-14lb. Journal of ThermalExcept for foams manufactured with CFC-11 and 1.0% or 1.5% of water, for which material inhomogeneity was higher than can be tolerated by the proposed test methodology, polyurethane foams manufactured with CFC-11 and 0.5% water, HCFC-123 and HCFC-141b showed long-term thermal performance similar to that of CFC-11 blown materials.

Testing Long-Term Thermal Resistance of Sprayed Polyurethane Foam

“…Instead of analyzing the total energy loss (or gain in a cooling climate) integrated over the 20 year period, one may, however, select such a reference time at which the thermal resistance of the 50 mm thick foam is equal to the average of the 20 year period. Applying a model of aging [8] for sprayed polyurethane foams as tested at NRC [1,3,4,9] the reference time was found to be somewhat shorter than the five year period previously postulated by an expert group [10]. Thus, the reference time of 1825 days will be used in further analysis.…”

“…However, in practice this is not the case. Then, as shown elsewhere [9] different aging curves exhibited by individual specimens can be brought together by normalizing them with the initial thermal resistivity value. The aging factor represents one point on such a normalized aging curve.…”

Effect of Time and Temperature on R-Value of Rigid Polyurethane Foam Insulation Manufactured with Alternative Blowing Agents

“…While results shown in Figures 9(a) through 9(c) display the same character of the r = r(T) curves, they also illustrate that direct comparisons between curves generated on different batches are difficult. Therefore, as previously postulated [3,6], one should perform two different types of measurements:…”

Assessment of Energy Rating of Polyurethane Spray Foam Walls: Procedure and Interim Results

“…More than a decade ago, Canadian and American SPF industry worked to develop better procedures enabling the transfer of technology developed with the chlorofluorocarbon (CFC) blown foams to the second generation of blowing agents, namely HCFC. The research was performed jointly between the SPF industry and the National Research Council of Canada (NRC) using an arbitrarily developed foam system -Base 88‖ [1,2].…”