Creation of Polymer Datasets with Targeted Backbones for Screening of High-Performance Membranes for Gas Separation.

A simple approach was developed to computationally construct a polymer dataset by combining simplified molecular-input line-entry system (SMILES) strings of a targeted polymer backbone and a variety of molecular fragments. This method was used to create 14 polymer datasets by combining seven polymer backbones and molecules from two large molecular datasets (MOSES and QM9). Polymer backbones that were studied include four polydimethylsiloxane (PDMS) based backbones, poly(ethylene oxide) (PEO), poly(allyl glycidyl ether) (PAGE), and polyphosphazene (PPZ).

Computational Screening of Physical Solvents for CO Pre-combustion Capture.

A computational scheme was used to screen physical solvents for CO pre-combustion capture by integrating the commercial NIST database, an in-house computational database, chem-informatics, and molecular modeling. A commercially available screened hydrophobic solvent, diethyl sebacate, was identified from the screening with favorable physical properties and promising absorption performance. The promising performance to use diethyl sebacate in CO pre-combustion capture has also been confirmed from experiments.

Scalable Polymeric Few-Nanometer Organosilica Membranes with Hydrothermal Stability for Selective Hydrogen Separation.

Nanoporous silica membranes exhibit excellent H/CO separation properties for sustainable H production and CO capture but are prepared via complicated thermal processes above 400 °C, which prevent their scalable production at a low cost. Here, we demonstrate the rapid fabrication (within 2 min) of ultrathin silica-like membranes (∼3 nm) via an oxygen plasma treatment of polydimethylsiloxane-based thin-film composite membranes at 20 °C. The resulting organosilica membranes unexpectedly exhibit H permeance of 280-930 GPU (1 GPU = 3.

Cross-Linked Polyphosphazene Blends as Robust CO Separation Membranes.

An effective cross-linking technique allows a viscous and highly gas-permeable hydrophilic polyphosphazene to be cast as solid membrane films. By judicious blending with other polyphosphazenes to improve the mechanical properties, a membrane exhibiting the highest CO permeability (610 barrer) among polyphosphazenes combined with a good CO/N selectivity (35) was synthesized and described here. The material demonstrates performance stability after 500 h of exposure to a coal-fired power plant flue gas, making it attractive for use in carbon capture applications.

Layer-by-layer assembly of metal-organic framework nanosheets with polymer.

Metal-organic framework (MOF) nanosheets are attracting more and more attention due to their tunable porous structure and two-dimensional shape. Adding MOF nanosheets into polymers can lead to improved properties, but the level of enhancement is usually thwarted by the difficulties in exfoliating and aligning these nanosheets within the polymer matrix. In order to establish a strategy for making polymer/MOF nanosheets composites with improved exfoliation and alignment, we combined MOF nanosheets and polymer using layer-by-layer (LbL) assembly for the first time.

Simple Fabrication Method for Mixed Matrix Membranes with in Situ MOF Growth for Gas Separation.

Metal organic framework (MOF)/polymer composite membranes are of interest for gas separations, as they often have performance that exceeds the neat polymer. However, traditional composite membranes, known as mixed matrix membranes (MMMs), can have complex and time-consuming preparation procedures. The MOF and polymer are traditionally prepared separately and require priming and mixing to ensure uniform distribution of particles and compatibility of the polymer-particle interface.

Continuous Flow Processing of ZIF-8 Membranes on Polymeric Porous Hollow Fiber Supports for CO Capture.

We have utilized an environmentally friendly synthesis approach for the accelerated growth of a selective inorganic membrane on a polymeric hollow fiber support for postcombustion carbon capture. Specifically, continuous defect-free ZIF-8 thin films were grown and anchored using continuous flow synthesis on the outer surface of porous supports using water as solvent. These membranes demonstrated CO permeance of 22 GPU and the highest reported CO/N selectivity of 52 for a continuous flow synthesized ZIF-8 membrane.