Thermal-Driven Self-Healing and Recyclable Waterborne Polyurethane Films Based on Reversible Covalent Interaction

2018 ◽  
Vol 6 (11) ◽  
pp. 14490-14500 ◽  
Author(s):  
Yuanlai Fang ◽  
Xiaosheng Du ◽  
Yuxu Jiang ◽  
Zongliang Du ◽  
Peiting Pan ◽  
...  
Keyword(s):  
Waterborne Polyurethane ◽  
Self Healing ◽  
Covalent Interaction ◽  
Reversible Covalent

Synthesis and self‐healing investigation of waterborne polyurethane based on reversible covalent bond

2022 ◽  
pp. 52144
Author(s):  
Jingyu Ren ◽  
Xiangbin Dong ◽  
Yanjie Duan ◽  
Lin Lin ◽  
Xiaowei Xu ◽  
...  
Keyword(s):  
Covalent Bond ◽  
Waterborne Polyurethane ◽  
Self Healing ◽  
Reversible Covalent

Acylhydrazones as Reversible Covalent Crosslinkers for Self-Healing Polymers

2015 ◽  
Vol 25 (22) ◽  
pp. 3295-3301 ◽  
Author(s):  
Natascha Kuhl ◽  
Stefan Bode ◽  
Ranjita K. Bose ◽  
Jürgen Vitz ◽  
Andreas Seifert ◽  
...  
Keyword(s):  
Self Healing ◽  
Reversible Covalent

An Unparalleled H-bonding and Ion-bonding Crosslinked Waterborne Polyurethane with Super Toughness and Unprecedented Fracture Energy

2021 ◽  
Author(s):  
Yuan Yao ◽  
Bo Liu ◽  
Ziyang Xu ◽  
Jianhai Yang ◽  
Wenguang Liu
Keyword(s):  
Mechanical Properties ◽  
Fracture Energy ◽  
Waterborne Polyurethane ◽  
Self Healing ◽  
Polyurethane Elastomers

Self-healing polyurethane elastomers have been extensively studied; however, developing an eco-friendly self-healable waterborne polyurethane (WPU) with exceptional mechanical properties remains a great challenge. Herein, we report healable, and highly tough...

Self-Healing Polymers Based on Reversible Covalent Bonds

2015 ◽  
pp. 1-58 ◽  
Author(s):  
Natascha Kuhl ◽  
Stefan Bode ◽  
Martin D. Hager ◽  
Ulrich S. Schubert
Keyword(s):  
Self Healing ◽  
Covalent Bonds ◽  
Reversible Covalent

New Chain Extenders for Self-Healing Polymers

2021 ◽  
Vol 899 ◽  
pp. 628-637
Author(s):  
Daria V. Zakharova ◽  
Zalina A. Lok’yaeva ◽  
Alexander A. Pavlov ◽  
Alexander V. Polezhaev
Keyword(s):  
Alder Reaction ◽  
Diels Alder ◽  
Hydroxyl Groups ◽  
Structural Fragment ◽  
Self Healing ◽  
Diels Alder Reaction ◽  
Small Series ◽  
Chain Extenders ◽  
Reversible Covalent ◽  
Thermochemical Parameters

We present here a small series of compounds designed to modify the polymer chain of various polyurethanes in order to introduce a structural fragment with the ability of thermally-triggered reversible covalent interactions. Bismaleimides (2a-2e) were synthesized from commercially available aromatic and aliphatic symmetric diamines (1a-1e) and were further introduced into the Diels-Alder reaction with furfuryl alcohol as dienophiles. The Diels-Alder adducts (3a-3e) were obtained as a mixture of endo- and exo-isomer. The presence of symmetrical hydroxyl groups in the structure of the obtained compounds makes them suitable as chain extenders of low molecular weight diisocyanate prepolymers. The presence of a thermally reversible Diels-Alder reaction adduct in the structure of potential chain-extenders opens a possibility to create unique materials with self-healing properties. All compounds obtained were characterized by 1H, 13C NMR, ESI-HRMS, and IR spectroscopy. The thermochemical parameters of the reverse Diels-Alder reaction were established using DSC analysis.

Construction of triple non-covalent interaction-based ultra-strong self-healing polymeric gels via frontal polymerization

2020 ◽  
Vol 8 (40) ◽  
pp. 14083-14091
Author(s):  
Ji-Dong Liu ◽  
Xiang-Yun Du ◽  
Cai-Feng Wang ◽  
Qing Li ◽  
Su Chen
Keyword(s):  
Frontal Polymerization ◽  
Self Healing ◽  
Smart Window ◽  
Covalent Interaction ◽  
Polymeric Gels ◽  
Non Covalent Interactions ◽  
Covalent Interactions

Robust and self-healing polymeric gels based on triple non-covalent interactions have been constructed for generation of a new self-healing thermoresponsive smart window.

scholarly journals Crystal Structures of KPC-2 β-Lactamase in Complex with 3-Nitrophenyl Boronic Acid and the Penam Sulfone PSR-3-226

2012 ◽  
Vol 56 (5) ◽  
pp. 2713-2718 ◽  
Author(s):  
Wei Ke ◽  
Christopher R. Bethel ◽  
Krisztina M. Papp-Wallace ◽  
Sundar Ram Reddy Pagadala ◽  
Micheal Nottingham ◽  
...  
Keyword(s):  
Crystal Structures ◽  
Active Site ◽  
Boronic Acid ◽  
Carbonyl Oxygen ◽  
Oxyanion Hole ◽  
Covalent Interaction ◽  
Class A ◽  
Inactivation Rate Constant ◽  
Reversible Covalent ◽  
Acid Compound

ABSTRACTClass A carbapenemases are a major threat to the potency of carbapenem antibiotics. A widespread carbapenemase, KPC-2, is not easily inhibited by β-lactamase inhibitors (i.e., clavulanic acid, sulbactam, and tazobactam). To explore different mechanisms of inhibition of KPC-2, we determined the crystal structures of KPC-2 with two β-lactamase inhibitors that follow different inactivation pathways and kinetics. The first complex is that of a small boronic acid compound, 3-nitrophenyl boronic acid (3-NPBA), bound to KPC-2 with 1.62-Å resolution. 3-NPBA demonstrated aKmvalue of 1.0 ± 0.1 μM (mean ± standard error) for KPC-2 and blocks the active site by making a reversible covalent interaction with the catalytic S70 residue. The two boron hydroxyl atoms of 3-NPBA are positioned in the oxyanion hole and the deacylation water pocket, respectively. In addition, the aromatic ring of 3-NPBA provides an edge-to-face interaction with W105 in the active site. The structure of KPC-2 with the penam sulfone PSR-3-226 was determined at 1.26-Å resolution. PSR-3-226 displayed aKmvalue of 3.8 ± 0.4 μM for KPC-2, and the inactivation rate constant (kinact) was 0.034 ± 0.003 s−1. When covalently bound to S70, PSR-3-226 forms atrans-enamine intermediate in the KPC-2 active site. The predominant active site interactions are generated via the carbonyl oxygen, which resides in the oxyanion hole, and the carboxyl moiety of PSR-3-226, which interacts with N132, N170, and E166. 3-NPBA and PSR-3-226 are the first β-lactamase inhibitors to be trapped as an acyl-enzyme complex with KPC-2. The structural and inhibitory insights gained here could aid in the design of potent KPC-2 inhibitors.

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