18 results about "Steric effects" patented technology

The invention discloses an electron transport material, an electron transport layer and an organic electroluminescent device, and belongs to the technical field of organic electroluminescent materials. The electron transport material is a nitrogen-containing heterocyclic compound, and simultaneously contains a pyridine ring and a pyrimidine ring connected with the pyridine ring. By introducing a power supply group with a steric effect, the nucleophilicity of similar nitrogen atoms on a pyrimidine ring connected with a pyridine ring can be shielded, so that the coordination activation n-doping effect of a target chelated nitrogen atom and an n-type doping agent is enhanced, and the coordination stability in the coordination activation n-doping effect is promoted; by introducing a power-supplying group to modify the nitrogen-containing heterocyclic unit, the electron nucleophilicity of the nitrogen-containing heterocyclic unit is enhanced, so that the electron transport material can form a more stable complex with the n-type dopant, and the conductivity of the electron transport layer of the light-emitting device is improved; therefore, the driving voltage of the organic light-emitting device can be reduced, the efficiency of the device is improved, and the service life is prolonged.

This invention discloses a chiral Pt metal-organic complex based on chiral Pt metal coordination, its preparation method, and its applications, belonging to the field of supramolecular chemistry. This method transfers chirality from the metal node to the tetraphenylethylene plane through metal coordination, forming a helical structure during crystallization to obtain a high-performance circularly polarized luminescent material. The introduction of a chiral binaphthyl group solves the problem of excessive distance between the chirality and the luminescent unit. Rigid coordination and steric effects are used to directionally induce a helical conformation in tetraphenylethylene, obtaining a single chiral molecule. Furthermore, this method connects the chiral group via covalent bonds and uses aggregation-induced emission molecules instead of traditional dyes to prepare materials with both a large luminescence asymmetry factor and high fluorescence quantum yield, expanding the application range of metal-organic cages.

The invention discloses a small molecule material based on condensed ring tert-butyl pyrene, a preparation method thereof and application of the small molecule material in an OLED (Organic Light Emitting Diode), and belongs to the technical field of organic photoelectric materials. The material is constructed by condensed ring tert-butyl pyrene, pyrene and carbazole are hybridized to form a novel carbazole condensed ring derivative with a large molecular conjugated structure and high stability, and the large conjugated plane structure can enhance the intermolecular stacking property, reduce the hole transport energy barrier and improve the hole mobility; due to the stereo steric effect of tert-butyl, excessive aggregation of molecules can be avoided, and charge transfer traps and non-radiative recombination are reduced; the phosphoric acid anchoring group can optimize interface bonding with the ITO anode, and the anode work function is matched to reduce the hole injection barrier. When the material is used as a core component of an OLED hole transport layer, the charge transport efficiency can be effectively improved, material crystallization and interface charge recombination in device operation can be inhibited, the brightness, efficiency and long-term stability of an OLED device can be remarkably improved, and the material has important significance in promoting the application of an OLED in the fields of high-end display and illumination.

The invention relates to acylhydrazone molecules capable of activating solid-state fluorescence or photochromism and preparation and application thereof, in the molecular structure, by changing a substituent R on a-N (R)-group on one side of benzoyl hydrazine, the conformation and accumulation mode of the molecules can be adjusted, so that selective activation of the fluorescence or photochromism property of the acylhydrazone molecules in a solid state is realized. When the substituent R is-H, the molecular conformation is planar, and the intermolecular accumulation is tight. In a solid state, the compound shows an excitation wavelength dependent fluorescence property, and when the wavelength of excitation light is changed, the fluorescence color is switched between blue and green. When the substituent R is-CH3, due to the steric effect of-CH3, the molecular conformation is distorted, and the accumulation among molecules becomes more loose. When ultraviolet light and visible light are alternately used for irradiation in a short time, the color of the powder can be rapidly switched between white and orange. The method provided by the invention is not influenced by R'on a benzene ring, and shows good universality.

The present application relates to the technical field of process chemicals, and discloses a positive photoresist stripping solution and a preparation method thereof, which comprises the following steps: step one, mixing monoethanolamine, catechol and sorbitol at 60-65 DEG C and constant temperature stirring to prepare a structure precursor with a dynamic viscosity of 350-500 mPa s; step two, mixing dimethyl sulfoxide and dipropylene glycol methyl ether and cooling to 5-10 DEG C to prepare a low-viscosity cold trap continuous phase, and establishing a temperature gradient of at least 50 DEG C and a viscosity gradient of 70 times with the precursor; and step three, shearing the precursor into the continuous phase at a controlled rate, and blocking the hydrogen bond network dissociation by using temperature difference and shear force, wherein the present application uses a non-equilibrium state thermal / rheological process to construct metastable amine clusters, reduces the corrosion to the metal substrate through physical steric effect, and realizes the decoupling of stripping efficiency and material compatibility.

The invention belongs to the field of organic photoelectric materials, and particularly relates to a micromolecule hole transport material with a functionalized periphery and application of the micromolecule hole transport material in the field of photoelectric devices such as perovskite solar cells. The molecular structure of the micromolecular hole transport material compound is shown as a general formula (I). Aiming at the problems of strong self-aggregation, weak passivation capability and the like of a traditional micromolecule self-assembly layer hole transport material, the invention of introducing a functional conjugated group to the periphery of a conjugated main skeleton is provided, the steric effect and cation-pi passivation effect of a peripheral functional group can be cooperated, the film-forming characteristic of a micromolecule self-assembly layer is improved, and the hole transport material has a good application prospect. And the interface defect passivation capability is enhanced. The micromolecular hole transport material based on the periphery functionalization can be used as an interface modification material to be applied to the fields of perovskite solar cells, organic solar cells, perovskite / organic electroluminescent devices, perovskite / organic photoelectric detectors and the like, and the efficiency and the stability of the devices are improved at the same time. Formula (I).

The present application relates to the technical field of biological medicine material and tissue damage repair preparation, and discloses a recombinant collagen skin barrier repair composition with the effect of ectoine, which comprises recombinant type III collagen, ectoine and deionized water as the balance in percentage by mass; the recombinant type III collagen is composed of components with specific proportions of long and short chains; the hydrated matrix is constructed by stirring the ectoine aqueous solution, and the collagen is added to anchor the side chain of the protein peptide chain in the matrix to form a linear extension conformation; the present application utilizes the physical steric effect of the ordered hydration structure induced by ectoine to block the environmental ion from stripping the surface-bound water of the protein, maintains the conformational stability of the collagen under the high ion strength of the inflammatory exudate, forms a dense net structure at the skin interface, and further reduces the transdermal water loss rate and enhances the residence of the active components at the damaged interface.

The present application relates to a kind of magnetic bead complex for enriching mRNA and its application, belong to biotechnology field.The present application provides a kind of magnetic bead complex for enriching mRNA, including magnetic bead, interval arm, primer and oligodT, wherein, primer is coupled on magnetic bead by interval arm, oligodT is connected by primer with interval arm, interval arm is C chain and / or base T, primer is used to amplify target mRNA and is combined on the cDNA of magnetic bead after reverse transcription, oligodT can be specifically combined with target mRNA;The magnetic bead complex for enriching mRNA is provided with interval arm between primer and magnetic bead, on the one hand, can reduce the steric effect when in situ cDNA pre-amplification, enhance the efficiency of amplification, on the other hand, interval arm makes mRNA enrichment using the magnetic bead complex, can be in the case of magnetic bead reverse transcription, while also can carry out PCR amplification reaction.

The application belongs to the field of separation and purification, and relates to a fixed phase for OPO column chromatography separation and purification, a preparation method and a separation and purification method and an OPO product. The structural formula of the fixed phase is: The fixed phase is used for column chromatography separation and purification of OPO, and can effectively separate OPO and OOP. Through the pi-complexation of silver ions and double bonds and the pi-pi stacking ability of the triazine structure, the fixed phase can distinguish the hydrophobicity and steric effect of the two isomers, so that high-efficiency separation is realized.

The invention relates to the technical field of organic electroluminescent materials, in particular to a boron-containing multiple resonance type thermal activation delayed fluorescence material and an organic electroluminescent device thereof. The boron-containing multi-resonance type thermal activation delayed fluorescence material provided by the invention has the core of a spirofluorene locking strategy, and compared with the prior art, the boron-containing multi-resonance type thermal activation delayed fluorescence material has the advantages that firstly, a spirofluorene unit is covalently connected with a B / N doped multi-resonance core through a rigid spirofluorene bridge, and a pi conjugated system is expanded on the premise of not damaging an MR resonance structure, so that red shift of emission is realized; secondly, due to the three-dimensional space steric effect of the spiro-carbon unit, on one hand, molecular vibration and conformational change are limited, relaxation of an excited state structure is inhibited, and a narrow spectrum is maintained; on the other hand, pi-pi accumulation among molecules is hindered, aggregation-induced quenching is effectively inhibited, and wide doping concentration stability is achieved; and the spiro carbon bridge enhances the molecular planarity and rigidity, improves the thermal stability of the material, and improves the stability of the device.

This application relates to the field of chemical technology and discloses a heterogeneous catalyst and a method for preparing thiols. The heterogeneous catalyst comprises an active component and an organophosphorus polymer ligand. The organophosphorus polymer ligand forms a coordination bond with the active component through a phosphorus element in its chemical structure. The active component includes at least one of Co and Rh elements. The organophosphorus polymer ligand is formed by polymerizing and sulfiding an organophosphorus monomer containing a carbon-carbon double bond. The sulfur content is 1%-20% based on the mass of the heterogeneous catalyst. The heterogeneous catalyst of this application exhibits high utilization of the active component and is not easily lost. The phosphorus ligand has a significant steric effect, which can improve the stereoselectivity of the target product. Simultaneously, a certain amount of sulfur can increase the binding force between the catalyst and H₂S, thereby improving the thiol yield.

The invention belongs to the technical field of catalyst preparation, and particularly relates to a biphenyl urea skeleton-based bimetallic catalyst, and a preparation method and application thereof. The bimetallic catalyst has a structure as shown in a formula 1, adopts a biphenyl urea skeleton, and is connected with group urea through carbon atoms, so that the structure of the bimetallic catalyst complex is more stable, and compared with the structure of a traditional catalyst, the bimetallic catalyst obtains a better spatial configuration; the introduction of urea enables the distortion degree of bond length and bond angle to be better coordinated with metal, the pocket-shaped structure better promotes the occurrence of polymerization reaction and the insertion of chain, and meanwhile, the steric effect and power supply capability of the ligand are adjusted by changing substituent groups, so that the polymerization performance of the metal catalyst is regulated and controlled; the molecular weight, molecular weight distribution, terminal double bond content, branched chain insertion rate and other properties of the polymer can be adjusted by selecting the types and the dosages of R1-R3 and metal salts in the bimetallic catalyst, so that the polymer can be applied to different fields.

The application discloses an electron transport material, an electron transport layer and an organic electroluminescent device, and belongs to the technical field of organic electroluminescent materials.The electron transport material is a compound containing a nitrogen-containing heterocycle, and simultaneously contains a pyridine ring and a pyrimidine ring connected with the pyridine ring.By introducing a power supply group with a steric effect, the nucleophilicity of similar nitrogen atoms on the pyrimidine ring connected with the pyridine ring can be shielded, so that the coordination activation n-doping effect of the target chelated nitrogen atom with the n-type dopant is enhanced, and the coordination stability in the coordination activation n-doping effect is promoted; and by introducing the power supply group to modify the nitrogen-containing heterocycle unit, the electronic nucleophilicity of the nitrogen-containing heterocycle unit is enhanced, so that the electron transport material can form a more stable complex with the n-type dopant, the conductivity of the electron transport layer of the light-emitting device is improved, so that the driving voltage of the organic electroluminescent device can be reduced, and the efficiency and service life of the device are improved.

The application discloses a kind of dendritic organic scintillator materials based on thermal activation delayed fluorescence and preparation method and application thereof, the organic scintillator material has the ternary structure of " acceptor core-donor skeleton-peripheral heavy atom capture antenna ": with thermal activation delayed fluorescence (TADF) molecule as core light unit, peripheral connection multiple branched chain containing heavy halogen atom aromatic functional group as X-ray absorption enhancement layer, isolated between by saturated flexible chain, the dendritic structure not only significantly improves the X-ray absorption coefficient of material using heavy atom effect, also effectively inhibits fluorescence quenching caused by heavy atom and the exciton quenching caused by intermolecular accumulation by space steric effect, so that the organic scintillator material of the application has high X-ray sensitivity, excellent radiation stability and high luminous efficiency, is suitable for high-performance X-ray imaging and radiation detection field.

The invention relates to a fluorine-free diamine monomer containing hydrophobic groups and a preparation method and application thereof, and belongs to the field of novel high-performance polyimide materials. The fluorine-free diamine monomer containing the hydrophobic group has a structure shown in a general formula (I), the fluorine-free diamine monomer containing the hydrophobic group has groups capable of providing a steric effect on ortho-positions R1, R2, R3 and R4 of aniline, and the probability that carbonyl oxygen in polyimide synthesized by the monomer is combined with water molecules can be reduced. The fluorine-free polyimide containing the hydrophobic group prepared from the fluorine-free diamine monomer containing the hydrophobic group has the advantages of low dielectric constant, low loss factor, high thermal stability and excellent solubility, can be used as a high-performance insulating base material, and meets the ultrahigh comprehensive performance requirement of a new generation of high-frequency and high-speed circuits on a polymer substrate; the method is suitable for the fields of super-large-scale integrated circuits, high-frequency high-speed circuit boards, photosensitive polyamideimide and the like

This invention discloses a method for preparing low-viscosity basic ferric phosphate slurry and its product. The preparation method is as follows: ferrous salt solution and phosphate salt solution are prepared and simultaneously added to a reaction vessel to obtain basic ferrous phosphate slurry; an oxidant and a viscosity reducer are added for an oxidation reaction to obtain low-viscosity basic ferric phosphate slurry; the viscosity reducer is 5027W dispersant, anionic surfactant, sodium pyrophosphate, sodium hexametaphosphate, or chromium-free lignin sulfonate. This invention controls the crystal nucleation and growth rate through stepwise feeding, combined with the electrostatic and steric effects of the viscosity reducer, inducing primary particles to form a spherical structure and inhibiting agglomeration. The resulting slurry has a primary particle size of 55-80 nm, a secondary particle size of 7-10 μm, a viscosity ≤15.0 mPa·s, and a sedimentation efficiency P of 1.00-2.00. This slurry has good fluidity, and the anhydrous ferric phosphate prepared by subsequent crystal transformation has high purity, which is beneficial for improving ferric phosphate production efficiency and equipment lifespan.

The application discloses an extraction solvent and an extraction method for stepwise recovery of vanadium and chromium in a solution by steric hindrance effect of an amide extractant, wherein the extraction solvent is composed of extraction solvent A and extraction solvent B; the extraction solvent A is composed of a large steric hindrance amide extractant and diluent A; the extraction solvent B is composed of a small steric hindrance amide extractant and diluent B; the large steric hindrance amide extractant and the small steric hindrance amide extractant are both alkyl-substituted amide extractants; and the diluent A and the diluent B are both inert organic solvents. The steric hindrance effect of the amide extractant in the extraction solvent is utilized to stepwise recover vanadium and chromium in the solution, and high-purity chromium-containing stripping liquid and vanadium-containing stripping liquid are obtained, which has the advantages of high extraction rate, high separation coefficient, high product purity, fast extraction kinetics, good regeneration of the extraction solvent and green harmlessness.