Adaptable thermal conductivity characterization of microporous membranes based on freestanding sensor-based 3ω technique

Adaptable thermal conductivity measurements of microporous membranes based on freestanding sensor-based 3 omega technique is proposed. The adaptability and flexibility of the freestanding sensor enable microporous membranes with various mechanical and thermal properties to be easily sandwiched between the freestanding sensor and a semi-infinite thermally conductive substrate, assembling into a five-layer substrate-membrane-sensor-membrane-substrate configuration. A theoretical model for the calculation of membrane's thermal conductivity is provided by comparing the temperature difference between the five-layer configuration and a three-layer substrate-sensor-substrate configuration. The well agreed experimental results with the theoretically calculated values indicate that the present strategy can be widely applied to the thermal properties characterization of microporous membranes in membrane distillation. (C) 2014 Elsevier Masson SAS. All rights reserved.