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Hopkinson, David

Publications and source records attributed to Hopkinson, David.

84 records · Page 5

Polymers of Intrinsic Microporosity Chemical Sorbents Utilizing Primary Amine Appendance Through Acid–Base and Hydrogen-Bonding Interactions

In this work, we introduce novel chemical sorbents based on polymers with intrinsic microporosity (PIMs). For the first time, alkylamines were incorporated in PIMs through an acid–base interaction to create a chemisorbent. The amine-appended PIMs not only showed a nearly four-fold enhancement in CO 2 loading capacity (36.4 cc/g at 0.15 bar and 298 K) and very high CO 2 /N 2 selectivity compared to neat PIM -1 but moreover proved to have stable performance when cycled between adsorption and desorption isotherms under both dry and humid conditions that are typical for postcombustion CO 2 capture.

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The effect of Poly(Ethylene oxide) cross-linking structure on the mechanical properties and CO 2 separation performance of an ion gel membrane

Ionic liquid gels of 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide plasticizing a cross-linked poly(ethylene oxide) are high performance CO 2 separation membranes. Here, the effect of polymer cross-link density on the ionic liquid stability, on the mechanical properties of the resulting films, and on the gas separation properties were studied. Cross-link density was modified by changing the chain length of ethoxylated diacrylate and triacrylate monomers, and by incorporating small amounts of short, multifunctional acrylate monomers. Without the ionic liquid acting as permanent plasticizer, higher cross-link density is associated with higher yield strength but lower strain at break, as expected. In a plasticized network, however, the loss in flexibility is not accompanied by higher yield strength, leaving ion gels made from highly cross-linked network more fragile than those having longer, more flexible chains. In conclusion, lowering cross-link density also allowed more ionic liquids to be incorporated as a phase stable gel and led to better CO 2 separation performance.

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Polymer for carbon dioxide capture and separation

One or more embodiments relate to providing substrate for separating a first gas component from a gaseous mixture, said substrate comprising a benzimidazole-linked polymer. Also provided is a method for synthesizing a substrate for separating a first gas component from a gaseous mixture, the method comprising performing a free condensation reaction between an aryl-o-diamine and an aryl-aldehyde to yield a benzimidazole-linked polymer. Other embodiments related to providing a CO2 separation membrane comprising benzimidazole-linked polymer residing within a matrix.

Hopkinson, David↗

Effect of Molecular Structure on the CO 2 Separation Properties of Hydrophobic Solvents Consisting of Grafted Poly Ethylene Glycol and Poly Dimethylsiloxane Units

This work describes the preparation of a set of nine new novel hydrophobic PEG-substituted solvents. These solvents include linear, T-shaped, and disubstituted conformations of the PEG grafted with PDMS molecule. The effect of changing both the molecular conformation and length of PEG side arm on the physical properties and CO 2 absorption capacity was studied. These solvents are intended for separation of CO 2 and H 2 in precombustion CO 2 capture and are intended to replace the current-state-of-the-art glycol-based solvents and operate at a higher temperature. In conclusion, the properties of the disubstituted solvents are exceptionally well suited for precombustion CO 2 capture applications because of their hydrophobicity, high CO 2 solubility, low evaporation rate, and lack of foaming.

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