Rapid Assessment of the Thermal Conductivity Performance of Aerogel Blanket
Aerogels are a class of ultralight, porous materials which are extremely thermally insulative. They are the only class of materials with a typical thermal conductivity which is lower than that of dry air (which is typically on the order of 0.025 W/mK – air is a very good thermal insulator). Although traditional aerogels were rigid, brittle materials making them inappropriate for use in applications requiring compressibility – for example, in textiles – or in applications where a flexible insulator is an advantage, such as in piping insulation, modern aerogels may be formulated with compressibility and flexibility in mind. Aerogel blankets are one such class of flexible aerogel material, which see applications in as diverse industries as construction and textiles, in addition to the more traditional aerospace and pipeline applications.
Recent advances in the C-Therm TCi Thermal Conductivity Analyzer’s sensor calibration has made the rapid testing of aerogel samples possible. Previous results were presented on commercially-available solid and powder aerogels such as Marketech aerogel, Cabot Lumira aerogel and Cabot Enova aerogel. This work continues on the previous work, expanding to a flexible aerogel blanket material.
A sample of commercially-available aerogel blanket was obtained from Aspen Aerogels, an industrial supplier. Using the C-Therm Compression Test Accessory (CTA), 1000gf was applied to the sample to mimic the expected application compressive force. The sample was tested at room temperature using a C-Therm TCi Thermal Conductivity Analyzer. The advantage of the TCi’s application in testing such materials is that it offers a fast, 3-second test of the performance of the insulation material, making it potentially useful as a quality control tool in manufacturing, and of great utility in speeding research throughput. The results are illustrated in the chart below:
The C-Therm TCi Thermal Conductivity Analyzer determined the thermal conductivity of the aerogel blanket to be 0.0139 W/mK, compared with a specification of 0.0140 W/mK. The difference between the measured thermal conductivity and the specification was within 1%, illustrating that the tested sample was consistent with its expected performance.