Stretchable, recyclable thermosets via photopolymerization and 3D printing of hemiacetal ester-based resins.
2023; 14 (44): 12535-12540
Achieving a circular plastics economy is one of our greatest environmental challenges, yet conventional mechanical recycling remains inadequate for thermoplastics and incompatible with thermosets. The next generation of plastic materials will be designed with the capacity for degradation and recycling at end-of-use. To address this opportunity in the burgeoning technologies of 3D printing and photolithography, we report a modular system for the production of degradable and recyclable thermosets via photopolymerization. The polyurethane backbone imparts robust, elastic, and tunable mechanical properties, while the use of hemiacetal ester linkages allows for facile degradation under mild acid. The synthetic design based on hemiacetal esters enables simple purification to regenerate a functional polyurethane diol.
View details for DOI 10.1039/d3sc03623e
View details for PubMedID 38020396
View details for PubMedCentralID PMC10646930
- Stretchable, recyclable thermosets <i>via</i> photopolymerization and 3D printing of hemiacetal ester-based resins CHEMICAL SCIENCE 2023
- Tunable, reusable, and recyclable perfluoropolyether periodic dynamic polymers with high underwater adhesion strength MATTER 2023; 6 (7): 2439-2453
Photoswitchable Binary Nanopore Conductance and Selective Electronic Detection of Single Biomolecules under Wavelength and Voltage Polarity Control
2022; 16 (4): 5537-5544
We fabricated photoregulated thin-film nanopores by covalently linking azobenzene photoswitches to silicon nitride pores with ∼10 nm diameters. The photoresponsive coatings could be repeatedly optically switched with deterministic ∼6 nm changes to the effective nanopore diameter and of ∼3× to the nanopore ionic conductance. The sensitivity to anionic DNA and a neutral complex carbohydrate biopolymer (maltodextrin) could be photoswitched "on" and "off" with an analyte selectivity set by applied voltage polarity. Photocontrol of nanopore state and mass transport characteristics is important for their use as ionic circuit elements (e.g., resistors and binary bits) and as chemically tuned filters. It expands single-molecule sensing capabilities in personalized medicine, genomics, glycomics, and, augmented by voltage polarity selectivity, especially in multiplexed biopolymer information storage schemes. We demonstrate repeatedly photocontrolled stable nanopore size, polarity, conductance, and sensing selectivity, by illumination wavelength and voltage polarity, with broad utility including single-molecule sensing of biologically and technologically important polymers.
View details for DOI 10.1021/acsnano.1c10039
View details for Web of Science ID 000813113000001
View details for PubMedID 35286058
Design of phase-transition molecular solar thermal energy storage compounds: compact molecules with high energy densities
2021; 57 (74): 9458-9461
A series of compact azobenzene derivatives were investigated as phase-transition molecular solar thermal energy storage compounds that exhibit maximum energy storage densities around 300 J g-1. The relative size and polarity of the functional groups on azobenzene were manifested to significantly influence the phase of isomers and their energy storage capacity.
View details for DOI 10.1039/d1cc03742k
View details for Web of Science ID 000689025700001
View details for PubMedID 34528978
- Solar energy conversion and storage by photoswitchable organic materials in solution, liquid, solid, and changing phases JOURNAL OF MATERIALS CHEMISTRY C 2021; 9 (35): 11444-11463
- Sunlight-activated phase change materials for controlled heat storage and triggered release JOURNAL OF MATERIALS CHEMISTRY A 2021; 9 (15): 9798-9808
Arylazopyrazoles for Long-Term Thermal Energy Storage and Optically Triggered Heat Release below 0 degrees C
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
2020; 142 (19): 8688-8695
Arylazopyrazole derivatives based on four core structures (4pzMe, 3pzH, 4pzH, and 4pzH-F2) and functionalized with a dodecanoate group were demonstrated to store thermal energy in their metastable Z isomer liquid phase and release the energy by optically triggered crystallization at -30 °C for the first time. Three heat storage-release schemes were discovered involving different activation methods (optical, thermal, or combined) for generating liquid-state Z isomers capable of storing thermal energy. Visible light irradiation induced the selective crystallization of the liquid phase via Z-to-E isomerization, and the latent heat stored in the liquid Z isomers was preserved for longer than 2 weeks unless optically triggered. Up to 92 kJ/mol of thermal energy was stored in the compounds, demonstrating remarkable thermal stability of Z isomers at high temperatures and liquid-phase stability at temperatures below 0 °C.
View details for DOI 10.1021/jacs.0c00374
View details for Web of Science ID 000535252100023
View details for PubMedID 32319773