Linking Silica Support Morphology to the Dynamics of Aminopolymers in Composites

Journal Article · Thu May 11 00:00:00 EDT 2017 · Langmuir

DOI:https://doi.org/10.1021/acs.langmuir.7b00283· OSTI ID:1376602

Carrillo, Jan-Michael Y. ^[1]; Potter, Matthew E. ^[2]; Sakwa-Novak, Miles A. ^[2]; Pang, Simon H. ^[2]; Jones, Christopher W. ^[2]; Sumpter, Bobby G. ^[1]

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1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
2. Georgia Inst. of Technology, Atlanta, GA (United States)

A combined computational and experimental approach is used to elucidate the effect of silica support morphology on polymer dynamics and CO₂ adsorption capacities in aminopolymer/silica composites. Furthermore, simulations are based on coarse-grained molecular dynamics simulations of aminopolymer composites where a branched aminopolymer, representing poly(ethylenimine) (PEI), is impregnated into different silica mesoporous supports. The morphology of the mesoporous supports varies from hexagonally packed cylindrical pores representing SBA-15, double gyroids representing KIT-6 and MCM-48, and cagelike structures representing SBA-16. In parallel, composites of PEI and the silica supports SBA-15, KIT-6, MCM-48, and SBA-16 are synthesized and characterized, including measuring their CO₂ uptake. Simulations predict that a 3D pore morphology, such as those of KIT-6, MCM-48, and SBA-16, will have faster segmental mobility and have lower probability of primary amine and surface silanol associations, which should translate to higher CO₂ uptake in comparison to a 2D pore morphology such as that of SBA-15. We found that KIT-6 has higher CO₂ uptake than SBA-15 at equivalent PEI loading, even though both supports have similar surface area and pore volume. But, this is not the case for the MCM-48 support, which has smaller pores, and SBA-16, whose pore structure rapidly degrades after PEI impregnation.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States). Oak Ridge Leadership Computing Facility (OLCF); Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Energy Frontier Research Centers (EFRC) (United States). Center for Understanding and Control of Acid Gas-induced Evolution of Materials for Energy (UNCAGE-ME)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
• DOE Contract Number: AC05-00OR22725; SC0012577
• OSTI ID: 1376602
• Journal Information: Langmuir, Journal Name: Langmuir Journal Issue: 22 Vol. 33; ISSN 0743-7463
• Publisher: American Chemical Society
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY