A healable waterborne polyurethane synergistically cross-linked by hydrogen bonds and covalent bonds for composite conductors

2020 ◽  
Vol 8 (15) ◽  
pp. 5280-5292 ◽  
Author(s):  
Yan Yang ◽  
Zushan Ye ◽  
Xiaoxuan Liu ◽  
Jiahui Su
Keyword(s):  
Hydrogen Bonds ◽  
Waterborne Polyurethane ◽  
Double Bonds ◽  
Covalent Bonds ◽  
Waterborne Polyurethanes ◽  
Composite Conductors

Healable waterborne polyurethanes synergistically cross-linked by dynamic hydrogen bonds and photo-curable double bonds for composite conductors.

Systhesis, Characterization and Spectroscopic Properties of (2E,6E)-2,6-Bis(2,3,4-tri-methoxy-benzylidene)cyclohexanone

2011 ◽  
Vol 396-398 ◽  
pp. 2338-2341
Author(s):  
Xing Chuan Wei ◽  
Zhi Li Liu ◽  
Kun Zhang ◽  
Zhi Yun Du ◽  
Xi Zheng
Keyword(s):  
Crystal Structure ◽  
Acetic Acid ◽  
Hydrogen Bonds ◽  
Title Compound ◽  
Spectroscopic Properties ◽  
Spectral Studies ◽  
Double Bonds ◽  
X Ray ◽  
Π Interactions ◽  
X Ray Crystallography

In this paper, (2E,6E)-2,6-Bis(2,3,4-tri-methoxy -benzylidene)cyclohexanone (omitted as tmbcho) (1) was obtained by the reaction of acetic acid, tetrahydrofuran, cyclohexanone and 2,3,4-tri-methoxy-benzaldehyde. Three non-classic hydrogen bonds were observed in the compound. X-ray crystallography shows that the crystal structure is stabilized by intermolecular C-H•••π interactions and it contains plenty of conjugated double bonds. The title compound was characterized by UV-vis and fluorescent spectral studies.

Photosensitive Polyimides

1989 ◽  
Vol 167 ◽  
Author(s):  
Hiroo Hiramoto
Keyword(s):  
Polymer Chains ◽  
Double Bonds ◽  
Acid Base ◽  
Film Properties ◽  
Covalent Bonds ◽  
Two Factors ◽  
Patterned Films ◽  
The Way

AbstractPhotosensitive polyimides are used as insulation and protection layers for microelectronics. They can easily give fine-patterned films with excellent characteristics of polyimides by photolithographic procedure.Photosensitive groups such as double bonds, azides, o-nitrobenzyl and o-naphthoquinonediazides. These photosensitive groups are incorporated to polymer chains through covalent bonds or acid-base ion bonds. Some polyimides have photosensitivity even without intentionally introduced photosensitive groups. Most of photosensitive polyimides are negative working, and a few of them are positive working.Characteristics of photosensitive polyimides are determined by two factors, the way of introducing photosensitive groups and the structures of polyimide backbone chains. Photosensitivity, resolution, purity and easiness of imidization mainly depends on the former factor. The film properties after curing are mainly determined by the latter. The film properties, however, are affected by the former when imide cyclization is imperfect.Photosensitive polyimides are widely used as protection and insulation layers of VLSI, multi-chip modules for computers, telecommunication, linephotosensors, thermal-heads, etc.

scholarly journals Synthetic scheme to improve the solid content of biodegradable waterborne polyurethane by changing the association relationships of hydrophilic fragments

RSC Advances ◽  
2020 ◽  
Vol 10 (48) ◽  
pp. 28680-28694 ◽  
Author(s):  
Zhihui Yang ◽  
Guangfeng Wu
Keyword(s):  
Ethylene Glycol ◽  
Waterborne Polyurethane ◽  
Solid Content ◽  
Synthetic Method ◽  
High Solid Content ◽  
Poly Ethylene Glycol ◽  
High Solid ◽  
Molecular Weights ◽  
Waterborne Polyurethanes ◽  
Poly Ethylene

A synthetic method was developed to prepare biodegradable waterborne polyurethanes (BHPUs) with a high solid content by introducing different molecular weights of poly(ethylene glycol) (PEG) into poly(ε-caprolactone) (PCL)-based polyurethanes.

scholarly journals Stabilization of N-, N,N-, N,N′-methylated and unsubstituted simple amidine salts by multifurcated hydrogen bonds

2006 ◽  
Vol 20 (4) ◽  
pp. 169-176 ◽  
Author(s):  
Jarosław Spychała
Keyword(s):  
Chemical Shift ◽  
Hydrogen Bonds ◽  
Chemical Shifts ◽  
2D Nmr ◽  
Biological Properties ◽  
Carbonyl Oxygen ◽  
Relative Strength ◽  
Intramolecular Interactions ◽  
Covalent Bonds ◽  
Natural Isotopic Abundance

In the light of the usefulness of amidines in medicinal chemistry, this paper considers the effects on biological properties and chemical reactivities of organic molecules affected by intramolecular interactions. The study of chemical shifts has been an important source of information on the electronic structure of amidine salts and their ability to form non-covalent bonds with nucleic acids. The NMR and IR results demonstrate that hydrogen bonds are a force for promoting chemical reactions. The thymine O2 carbonyl oxygen in a close proximity to the amidinium cation does interact with the appropriately spaced amidinium NH donor moieties. The1H-15N 2D NMR (GHSQC and GHMBC) spectra with natural isotopic abundance of15N fully confirm the intramolecular character of the bonds. A rule able to estimate the relative strength of the new multifurcated hydrogen bonds is given. The appearance of the ΔδNHchemical shift differences near zero is due to the strong intramolecular interactions. The strength of the H-bond donation by acetamidines is reflected in the N–H dissociation/recombination process (positive charge shift has been invoked to explain other effects on benzamidines). The temperature dependence of chemical shift for the amidine NH protons in dimethyl sulfoxide solutions is herein discussed.

Influence of the 2,2-Dimethylol Propionic Acid Content on the Structure-Properties of Waterborne Polyurethane

2012 ◽  
Vol 476-478 ◽  
pp. 2116-2121 ◽  
Author(s):  
Zheng Xiang Wang ◽  
Jian Long Wang ◽  
Li Zheng Gu
Keyword(s):  
Propionic Acid ◽  
Waterborne Polyurethane ◽  
Peel Strength ◽  
Scanning Calorimetry ◽  
Elongation At Break ◽  
Waterborne Polyurethanes ◽  
Fourier Transformed Infrared Spectroscopy ◽  
Lower Elongation ◽  
Dimethylol Propionic Acid ◽  
Structure Properties

Abstract. Series waterborne polyurethane (WPU) dispersions with different 2,2-dimethylol propionic acid (DMPA) content were synthesized by the prepolymer method. Different configurations in the waterborne polyurethanes were obtained by varying the DMPA content. The structure-properties of the WPU dispersions were characterized by Fourier transformed infrared spectroscopy, Thermogravimetric analysis, differential scanning calorimetry, Zetasizer nano etc. The results indicated that the amount of urethane and urea groups (hard segment) increased in the structure of WPU chains with the increasing content of DMPA. In the meantime, the degree of micro-phase separation increased. On the other hand, as the content of DMPA increased, the particle size, the thermal stability and T-peel strength decreased. Moreover, the increased content of DMPA resulted in higher tensile strength and hardness, but lower elongation at break.

Polymorphism of 2,5-Diphenyl-1,4-distyrylbenzene with Two cis Double Bonds:  The Essential Role of Aromatic CH/π Hydrogen Bonds

2005 ◽  
Vol 5 (5) ◽  
pp. 1959-1964 ◽  
Author(s):  
Zengqi Xie ◽  
Linlin Liu ◽  
Bing Yang ◽  
Guangdi Yang ◽  
Ling Ye ◽  
...  
Keyword(s):  
Hydrogen Bonds ◽  
Essential Role ◽  
Double Bonds
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