Swelling of Star Polymer Thin Films Exposed to Supercritical Carbon Dioxide

Published

March 14, 2024

Author(s)

Ayse Caglayan, Sushil Satija, David Uhrig, Kunlun Hong, Tadanori Koga, Bulent Akgun

Abstract

Impact of polymer chain architecture on the swelling of supported single-layer polymer thin films with thicknesses below 80 nm in the presence of supercritical CO2 (scCO2) is investigated using in-situ neutron reflectivity (NR) and exsitu x-ray reflectivity (XR). 4-arm star and 8-arm star deuterated polystyrene (dPS) having similar total molecular weights are used. NR results revealed that the magnitude of the swelling for star polymers increases proportionally with decreasing dry film thicknesses similar to linear polymers. For film thicknesses above 5Rg, architectural differences have no impact on the swelling behavior. However, below 5Rg as the branching increases from linear to 4-arm star and to 8-arm star, swelling decreases due to the presence of a relatively thicker adsorbed layer formed by more branched architectures. Ex-situ XR measurements verified that star architectures swell less than linear architecture and provided new information about the vitrification of the films through rapid quenching and its relation to the amount of CO2 retention.

Citation

Journal of Polymer Science

Volume

62

Issue

6

Pub Type

Journals

Download Paper

https://doi.org/10.1002/pol.20230720

Local Download

Citation

Caglayan, A. , Satija, S. , Uhrig, D. , Hong, K. , Koga, T. and Akgun, B. (2024), Swelling of Star Polymer Thin Films Exposed to Supercritical Carbon Dioxide, Journal of Polymer Science, [online], https://doi.org/10.1002/pol.20230720, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=959049 (Accessed November 23, 2024)