Application of “Rule of Mass Shift” to Sulfur and Phosphorus Functional Groups that Have Coordinate Covalent Bonds to Oxygen

Design of materials with novel sensitivities and smart behaviour is important for the development of smart systems with automated responsiveness. We have recently reported the synthesis of hydrogels, cross-linked by N,N'-diallyltartardiamide (DAT). The covalent DAT-crosslinking points have vicinal diols which can be easily cleaved with periodate, generating valuable a-oxo-aldehyde functional groups, useful for further chemical modification. Based on those findings, we envisioned that a self-healable hydrogel could be obtained by incorporation of primary amino functional groups, from <a>2-aminoethyl methacrylate </a>hydrochloride (AEMA), coexisting with DAT into the same network. The a-oxo-aldehyde groups generated after the reaction with periodate would arise in the immediate environment of amine groups to form imine cross-links. For this purpose, DAT-crosslinked hydrogels were synthesized and carefully characterized. The cleavage of DAT-crosslinks with periodate promoted changes in the mechanical and swelling properties of the materials. As expected, a self-healing behavior was observed, based on the spontaneous formation of imine covalent bonds. In addition, we surprisingly found a combination of fast vicinal diols cleavage and a low speed self-crosslinking reaction by imine formation. Consequently, it was found a time-window in which a periodate-treated polymer was obtained in a transient liquid state, which can be exploited to choose the final shape of the material, before automated gelling. The singular properties attained on these hydrogels could be useful for developing sensors, actuators, among other smart systems.

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2. The fundamentals

Organic Chemistry: A Very Short Introduction ◽

10.1093/actrade/9780198759775.003.0002 ◽

2017 ◽

pp. 6-24

Author(s):

Graham Patrick

Keyword(s):

Functional Groups ◽

Atomic Number ◽

Outer Shell ◽

Intramolecular Interactions ◽

Covalent Bonds ◽

Linear Chains ◽

Element Carbon ◽

Carbon Carbon Bonds ◽

Valence Electrons ◽

Branched Chains

‘The fundamentals’ investigates why the element carbon is so suited for the generation of so many compounds. Carbon has atomic number six, meaning it has six protons in its nucleus and six electrons around the nucleus, four of which are valence electrons held in the outer shell. Carbon achieves a stable, full outer shell of electrons by sharing electrons with other elements and other carbon atoms to form covalent bonds. The carbon–carbon bonds are one of the principle reasons why so many organic molecules are possible, including linear chains, branched chains, and rings. The naming of compounds and identification of structures is also explained along with stereochemistry, functional groups, and intermolecular and intramolecular interactions.

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Imine Based Self-Healing Hydrogel Triggered by Periodate

10.26434/chemrxiv.12592322.v1 ◽

2020 ◽

Author(s):

Alexis Wolfel ◽

Cecilia Inés Alvarez Igarzabal ◽

Marcelo Ricardo Romero

Keyword(s):

Functional Groups ◽

Time Window ◽

Crosslinking Reaction ◽

Self Healing ◽

Swelling Properties ◽

Covalent Bonds ◽

Smart Systems ◽

Primary Amino ◽

Vicinal Diols ◽

Aldehyde Groups

Design of materials with novel sensitivities and smart behaviour is important for the development of smart systems with automated responsiveness. We have recently reported the synthesis of hydrogels, cross-linked by N,N'-diallyltartardiamide (DAT). The covalent DAT-crosslinking points have vicinal diols which can be easily cleaved with periodate, generating valuable a-oxo-aldehyde functional groups, useful for further chemical modification. Based on those findings, we envisioned that a self-healable hydrogel could be obtained by incorporation of primary amino functional groups, from <a>2-aminoethyl methacrylate </a>hydrochloride (AEMA), coexisting with DAT into the same network. The a-oxo-aldehyde groups generated after the reaction with periodate would arise in the immediate environment of amine groups to form imine cross-links. For this purpose, DAT-crosslinked hydrogels were synthesized and carefully characterized. The cleavage of DAT-crosslinks with periodate promoted changes in the mechanical and swelling properties of the materials. As expected, a self-healing behavior was observed, based on the spontaneous formation of imine covalent bonds. In addition, we surprisingly found a combination of fast vicinal diols cleavage and a low speed self-crosslinking reaction by imine formation. Consequently, it was found a time-window in which a periodate-treated polymer was obtained in a transient liquid state, which can be exploited to choose the final shape of the material, before automated gelling. The singular properties attained on these hydrogels could be useful for developing sensors, actuators, among other smart systems.

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X-ray photo-electron spectroscopic studies of cryogenic and plasma surface-treated z-pins

Journal of Composite Materials ◽

10.1177/0021998317691811 ◽

2017 ◽

Vol 51 (8) ◽

pp. 1155-1166 ◽

Cited By ~ 8

Author(s):

André Knopp ◽

Gerhard Scharr

Keyword(s):

Surface Roughness ◽

Plasma Treatment ◽

Functional Groups ◽

Bulk Material ◽

Cryogenic Treatment ◽

Covalent Bonds ◽

Plasma Surface ◽

X Ray ◽

Load Transmission ◽

The Impact

The mechanical properties of composite materials are primarily dependent on the load transmission between their components. Especially, the fracture performance of a fibre-reinforced polymer made of a preimpregnated fibres (prepreg) with a three-dimensional z-pin reinforcement can be influenced by the interface characteristics between pins and laminate. X-ray photo-electron spectroscopic (XPS) analysis and scanning electron microscopic (SEM) studies of untreated, cryogenic and plasma surface-treated z-pins were carried out to determine the effect of surface treatments on chemical composition, formation of functional groups and topography of pin surface. Pullout tests were conducted to investigate the impact of a surface treatment on the bridging forces, which have significant influence on delamination toughness of a z-pinned laminate. It was pointed out that a cryogenic treatment cannot lead to an increase of oxygen or nitrogen functional groups at the z-pin surface. Nevertheless, the pullout forces can be increased which are caused by an increased surface roughness. However, with a plasma treatment, an oxygen and nitrogen functionalization can be reached. An increase of the O/C ratio with all plasma treatments can be determined. Summarizing the results, it can be shown that oxygen functional groups can be generated by a plasma treatment. These groups are able to establish covalent bonds between z-pin surface and bulk material, which can lead to a better load transmission between the pins and laminate and thus to higher fracture properties. The increased pullout forces result from a combination of improved adhesion between pins and laminate and increased interlocking effects, due to the higher surface roughness after plasma treatment.

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Cell-mimic polymersome-shielded islets for long-term immune protection of neonatal porcine islet-like cell clusters

Journal of Materials Chemistry B ◽

10.1039/c9tb02270h ◽

2020 ◽

Vol 8 (12) ◽

pp. 2476-2482 ◽

Cited By ~ 1

Author(s):

Hyun-Ouk Kim ◽

Sang Hoon Lee ◽

Woonsung Na ◽

Jong-Woo Lim ◽

Geunseon Park ◽

...

Keyword(s):

Hydrogen Bonds ◽

Functional Groups ◽

Electrostatic Interactions ◽

Survival Function ◽

Amine Group ◽

Immune Protection ◽

Covalent Bonds ◽

Porcine Islet ◽

Selective Permeability

A PSome-shielded NPCC is achieved by binding the surface amine group of NPCCs and various functional groups of the PSome. The coating utilizes interaction of the NPCC surface and PSomes that have covalent bonds, electrostatic interactions, and hydrogen bonds. Also, PSomes coated NPCCs have selective permeability necessary for NPCC survival, function and immune protection.

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Layer-by-Layer Molecular Assembly Approaches to the Construction of Thin Films Having High Second-Order Optical Nonlinearities

MRS Proceedings ◽

10.1557/proc-247-779 ◽

1992 ◽

Vol 247 ◽

Cited By ~ 2

Author(s):

David S. Allan ◽

Fuyuhiko Kubota ◽

Ashok K. Kakkar ◽

Tobin J. Marks ◽

Tongguang Zhang ◽

...

Keyword(s):

Thin Films ◽

Second Harmonic Generation ◽

Functional Groups ◽

Harmonic Generation ◽

Second Harmonic ◽

Substrate Surface ◽

Molecular Assembly ◽

Layer By Layer ◽

Covalent Bonds ◽

Second Harmonic Generation Efficiency

ABSTRACTChromophoric multilayer thin films exhibiting efficient second harmonic generation have been constructed on inorganic substrates via a stepwise layer-by-layer process using molecular self-assembly techniques. In each step, chemical species bearing appropriate functional groups form covalent bonds with functional groups deposited in the previous step. Bulk acentricity is achieved by the orientation of chromophore-containing layers outward from the substrate surface. A new chromophore having comparable hyperpolarizability but different steric and transparency characteristics than the stilbazolium chromophore used previously has been incorporated into self-assembled films. The large effects of octachlorotrisiloxane capping on the structure of these films have been investigated by second harmonic generation and X-ray reflectivity measurements. Novel in situ measurements of second harmonic generation efficiency as a function of chromophore layer growth are described and provide information useful for optimizing deposition conditions and understanding the film growth process.

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Effects of Electron Beam Irradiation on Mechanical and Thermal Shrinkage Properties of Boehmite/HDPE Nanocomposite Film

Nanomaterials ◽

10.3390/nano11030777 ◽

2021 ◽

Vol 11 (3) ◽

pp. 777

Author(s):

Ju Hyuk Lee ◽

Heon Yong Jeong ◽

Sang Yoon Lee ◽

Sung Oh Cho

Keyword(s):

Electron Beam ◽

Functional Groups ◽

Electron Irradiation ◽

Electron Beam Irradiation ◽

Thermal Shrinkage ◽

Hydroxyl Groups ◽

Melt Blending ◽

Beam Irradiation ◽

Covalent Bonds ◽

Surface Modified

Nanocomposites comprising high-density polyethylene (HDPE) and boehmite (BA) nanoparticles were prepared by melt blending and subsequently irradiated with electrons. Electron irradiation of HDPE causes crosslinking and, in the presence of BA, generates ketone functional groups. The functional groups can then form hydrogen bonds with the hydroxyl groups on the surface of the BA. Additionally, if the BA is surface modified by vinyltrimethoxysilane (vBA), it can covalently bond with the HDPE by irradiation-induced radical grafting. The strong covalent bonds generated by electron beam irradiation allow the desirable properties of the nanofiller to be transferred to the rest of the nanocomposite. Since EB irradiation produces a great number of strong covalent bonds between vBA nanoparticles and HDPE, the modulus of elasticity, yield strength, and resistance to thermal shrinkage are enhanced by electron irradiation.

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Physical and Chemical Study of the Structure and Activity of Biopolymer Matrices Based on a Complex of Redox Enzymes

Bulletin of Science and Practice ◽

10.33619/2414-2948/60/01 ◽

2020 ◽

Vol 6 (11) ◽

pp. 12-22

Author(s):

N. Lakina ◽

V. Doluda ◽

G. Rabinovich ◽

M. Lakina ◽

A. Sivenok

Keyword(s):

Functional Groups ◽

Chemical Study ◽

Comparative Characteristic ◽

Redox Enzymes ◽

Covalent Bonds ◽

High Sorption Capacity ◽

The Matrix ◽

High Sorption ◽

Physical And Chemical ◽

Structure And Activity

The paper presents experimental results on an effective method of using a complex of redox enzymes of the oxidoreductase class: glucooxidase (CF 1.1.3.4) and peroxidase (CF 1.11.1.7). Literature data confirming an increase in the potential of the redox reaction with the additional introduction of peroxidase, which decomposes hydrogen peroxide during the reaction used in the production of biofuel elements, are presented. The enzyme complex was included in polymer matrices of polyvinylpyrrolidone and acetylcellulose, which have a large number of functional groups, such as amide, hydroxyl, and carboxyl, capable of forming strong covalent bonds with enzymes, as well as a high sorption capacity to proteins. The paper presents a comparative characteristic of the activities of biopolymer complexes. The data of the Fourier-IR spectroscopy prove the formation of strong covalent bonds between the functional groups of enzymes and the matrix used.

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Optimization of Foamed Polyurethane/Ground Tire Rubber Composites Manufacturing

Materials Proceedings ◽

10.3390/iocps2021-11244 ◽

2021 ◽

Vol 7 (1) ◽

pp. 12

Author(s):

Adam Olszewski ◽

Paulina Kosmela ◽

Łukasz Zedler ◽

Krzysztof Formela ◽

Aleksander Hejna

Keyword(s):

Functional Groups ◽

Mechanical Performance ◽

Polyurethane Foams ◽

Rubber Composites ◽

Covalent Bonds ◽

Tire Rubber ◽

Ground Tire Rubber ◽

Composites Manufacturing ◽

Enormous Amount ◽

Fire Threat

The development of the automotive sector and the increasing number of vehicles all over the world poses multiple threats to the environment. One of them, probably not so emphasized as others, is the enormous amount of post-consumer car tires. Due to the potential fire threat, waste tires are considered as dangerous waste, which should not be landfilled, so it is essential to develop efficient methods of their utilization. One of the possibilities is their shredding and application of resulting ground tire rubber (GTR) as filler for polymer composites, which could take advantage of the excellent mechanical performance of car tires. Nevertheless, due to the poor compatibility with majority of polymer matrices, prior to the application, surface of GTR particles should be modified and activated. In the presented work, the introduction of thermo-mechanically modified GTR into flexible foamed polyurethane matrix was analyzed. Isocyanates can be found among the compounds applied during manufacturing of polyurethane foams, which are able to react and generate covalent bonds with the functional groups present on the surface of modified GTR. Such an effect can noticeably enhance the interfacial interactions and boost up the mechanical performance. Nevertheless, it requires the adjustment of formulations used during manufacturing of foams. Therefore, for better understanding of the process foams with varying isocyanate index (from 0.8 to 1.2) were prepared with and without taking into account the possible interactions with functional groups of GTR. For comparison, an unfilled matrix and composite containing deactivated GTR were also prepared.

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