VOC-Induced Flexing of Single and Multilayer Polyethylene Films As Gas Sensors
2016 (English)In: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 8, no 15, 9946-9953 p.Article in journal (Refereed) PublishedText
The differential swelling and bending of multilayer polymeric films due to the dissimilar uptake of volatile organic compounds (VOCs; n-hexane, limonene) in the different layers was studied. Motions of thin polyethylene films triggered by the penetrant were investigated to learn more about how their deformation is related to VOC absorption. Single layers of metallocene or low-density polyethylene, and multilayers (2-288-layers) of these in alternating positions were considered. Single-, 24-, and 288 layer films displayed no motion when uniformly subjected to VOCs, but they could display simple curving modes when only one side of the film was wetted with a liquid VOC. Two-layer films displayed simple bending when uniformly subjected to VOCs due to the different swelling in the two layers, but when the VOC was applied to only one side of the film, more complex modes of motion as well as dynamic oscillations were observed (e.g., constant amplitude wagging at 2 Hz for ca. 50 s until all the VOC had evaporated). Diffusion modeling was used to study the transport behavior of VOCs inside the films and the different bending modes. Finally a prototype VOC sensor was developed, where the reproducible curving of the two-layer film was calibrated with n-hexane. The sensor is simple, cost-efficient, and nondestructive and requires no electricity.
Place, publisher, year, edition, pages
American Chemical Society (ACS), 2016. Vol. 8, no 15, 9946-9953 p.
VOC sensor, multilayer films, modeling, flexing, polyethylene
IdentifiersURN: urn:nbn:se:kth:diva-187820DOI: 10.1021/acsami.6b01178ISI: 000374812000047ScopusID: 2-s2.0-84966293370OAI: oai:DiVA.org:kth-187820DiVA: diva2:931976
QC 201605312016-05-312016-05-302016-05-31Bibliographically approved