William R. Dichtel’s research while affiliated with Northwestern University and other places

... Catenanes (i.e., from the latin word catena, which means chain) are chainlike molecules mechanically interlocked where the molecules forming the chain are interlocked by mechanical bonds [21][22][23] instead of covalent bonds. Therefore, are classified as MIMs 24,25 . To separate one of the mechanically interlocked components, it is necessary to cleave a chemical bond; thus, the whole interlocked structure can be considered a molecule 26 . ...

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Mechanical interlocking of metal organic cages

... This state of play requires immediate action, including the development of PFAS removal approaches [2][3][4] and responsible management of PFAS-contaminated waste streams 8,9 . The PFAS degradation methods reported to date include chemical-and photochemical-initiated oxidation and reduction processes [10][11][12][13] , mechanical [14][15][16][17][18][19][20][21][22][23][24] and base-assisted destruction, including low-temperature mineralization 25,26 , and incineration 27 among other techniques 28,29 (Fig. 1a). ...

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Phosphate-enabled mechanochemical PFAS destruction for fluoride reuse

... Therefore, there is a need for new sustainable and cost-efficient treatment processes. Previous research on adsorption-based methods has focused on GAC filtration [14][15][16], biochar [17,18], cyclodextrin-based adsorbents, amorphous aluminium hydroxide, (organo)clays [17,[19][20][21], styrenic β-cyclodextrin polymers [22], and polymeric anion exchange resins (AERs) [23,24]. AERs are particularly promising due to their established use in treating other common water contaminants such as sulphate, chromate, nitrate, chloride, and perchlorate [14], as well as due to their demonstrated effectiveness to treat PFASs for groundwater remediation [24,25]. ...

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The effect of inorganic anions on the adsorption of perfluoroalkyl acids to various polymeric anion exchange resins

... [8,12] On the other hand, a deeper understanding of the crystallization mechanism of COFs could significantly address the challenges associated with crystal growth, thereby circumventing the traditional, labor-intensive process of empirical synthesis and screening. [13] However, a systematic investigation into the driving forces, kinetics, and mechanisms underlying the growth of single-crystal COFs has yet to be reported. ...

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Supersaturation‐Controlled Single‐Crystal Growth of Covalent Organic Frameworks with Binary Solvents

... Adsorbents incorporated by alginate (alg.) and cyclodextrin (β-CD) polymers, including hydrogels and IERs have recently been utilized to remove PFAS [67][68][69][70][71]. The cyclodextrin polymers outperform activated carbon for the removal of PFAS under real groundwater matrices [28]. ...

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Comparative immobilization of 30 PFAS mixtures onto biochar, clay, nanoparticle, and polymer derived engineered adsorbents: Machine learning insights into carbon chain length and removal mechanism

... This synthesis is achieved through the copolymerization of [2-(methacryloyloxy)ethyl] trimethylammonium chloride (MATMA) solution and StyDex (Figures 18a and b). [96] Batch adsorption experiments indicate that this polymer selectively adsorbs contaminants, successfully removing sixout of 13 tested pollutants and demonstrating reduced adsorption inhibition in wastewater compared to granular AC. It reaches equilibrium removal within one hour for PFOA, perfluorohexanoic acid (PFHxA), PFHxS, and DCF, with observed rate constants of 6.42, 4.48, 11.0, and 3.57 g μg À 1 h À 1 , respectively. ...

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Opportunity and Challenge of Advanced Porous Sorbents for PFAS Removal

... 48 and 49). Laboratory SAXS analysis shows that the DTMP-TFT films catalyzed by acid or base exhibit a similar degree of crystallinity ( Supplementary Fig. 50) 41,42 . The weakened crystallinity of 2DCP thin film and powder probably originates from the fact that the long alkyl chain affects the stacking and crystallizing process (Supplementary Fig. 51). ...

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Synthesis of crystalline two-dimensional conjugated polymers through irreversible chemistry under mild conditions

... Additionally, DCC enables the creation of foams that are easier to recycle, reducing the environmental impact of foam waste and increasing the lifetime of foam-based products. 16,21,22 3D printing offers a way to create polymer objects with simple or complex structures. 23,24 With 3D printing, foam architectures not possible by traditional manufacturing can be achieved, creating foams with better resolutions and complex shapes. ...

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3D printable polymer foams with tunable expansion and mechanical properties enabled by catalyst-free dynamic covalent chemistry

... Porphyrins are ubiquitous in biology and chemistry and play crucial roles in, for example, oxygen transport and storage in blood, charge transfer in cellular respiration, and photosynthesis in plants. 1,2 Their synthetic tunability 3 make porphyrins ideal in advancing bioinspired charge and energy transport and storage technologies, 4-7 especially as they offer a convenient chemical scaffold that can be functionalized with substituents, 8,9 paired with transition metals, 10 or wreathed together in polymer chains [11][12][13][14] to tailor and exploit their optoelectronic properties. Numerous studies have turned to sophisticated multidimensional spectroscopies to disentangle the palette of spectral features generated by porphyrin and porphyrin-like systems. ...

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Symmetry breaking fluctuations split the porphyrin Q bands

... The two bands observed between 2936 and 2860 cm −1 are attributed to symmetric and nonsymmetric stretching of the C─H bond of carbonyl groups. [21] The apparent absorption peaks at 1720 cm −1 and 1235 cm −1 are typical bands for the stretching vibrations of C═O and C─O (from ─N─CO─), respectively. [22] Notably, the peak at 1630 cm −1 is associated with the stretching vibration of C═O, which is not present in PBU, thus providing convincing evidence for the introduction of piperazine monomers. ...

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Polyurethane‐Based Shape Memory Compression Stockings with Antimicrobial and Pressure Regulating Properties for the Relief of Chronic Venous Disease