- Author
-
Zarr, R. R.
|
Nguyen, T.
- Title
- Effects of Humidity and Elevated Temperature on the Density and Thermal Conductivity of a Rigid Polyisocyanurate Foam Co-Blown With CCI₃F and CO₂.
- Coporate
- National Institute of Standards and Technology, Gaithersburg, MD
- Journal
-
Journal of Thermal Insulation and Building Environments,
Vol. 17,
330-350,
April 1994
- Book or Conf
- Society of the Plastics Industry of Canada's. Workshop on Long-Term Performance of Cellular Plastics, 3rd International. October 4-6, 1993,
Ontario, Canada,
1-21 p.,
['1993', '1994']
- Keywords
-
polyisocyanurate foam
|
humidity
|
temperature
|
density effects
|
thermal conductivity
|
rigid foam
|
trichlorofluoromethane
|
carbon dioxide
- Abstract
- Measurements of density and apparent thermal conductivity are presented for specimens of rigid polyisocyanurate (PIR) foam cut from a commercial insulation co-blown with trichlorofluoromethane (CCI₃F) and carbon dioxide (CO₂). Eight specimens, nominally 580 by 580 mm, were prepared from two boards (1.2 by 2.4 m by 50 mm) of foam laminated with permeable facers. Facers and excess foam were removed by sanding the specimens to a thickness of about 27 mm. Four specimens were placed in ambient conditions of 22 deg C and 40% relative humidity (RH). The other four specimens were each placed in one of the following environments: [1] 60 deg C and <10% RH; [2] 60 deg C and 40% RH; [3] 60 deg C and 60% RH; and, [4] 60 deg C and 75% RH. Measurements of apparent thermal conductivity were conducted at 24 deg C and a temperature difference of 22 deg C using a heat-flow-meter apparatus. Measurements were conducted over a period of 372 days at approximately 50-day intervals. Curves of specimen mass, volume, density, and thermal conductivity versus time are presented and the implications of changes in these properties are discussed.