20 results about "Azocane" patented technology

The invention discloses a graphite piece silicon carbide coating and a preparation method thereof, and belongs to the technical field of inorganic non-metallic materials. The method comprises the following steps: firstly, carrying out surface polishing, cleaning and drying pretreatment on a graphite piece; then a solution containing phosphinazine functionalized silazane and a boron-silicon carlamide compound is adopted for spraying the pretreated graphite piece, drying and curing are conducted, and a surface modification layer is formed; and finally, placing the surface-modified graphite piece in chemical vapor deposition equipment, and depositing at specific temperature, pressure and atmosphere to form the silicon carbide coating. According to the method, uniform nucleation and crystallization of the silicon carbide coating are effectively promoted through unique surface modification treatment, and the compactness and uniformity of the coating and the binding force of the coating and a matrix are remarkably improved. The obtained coating graphite piece has excellent thermal corrosion resistance, oxidation resistance and mechanical property, the service life and the use frequency of the coating graphite piece in semiconductor epitaxial equipment are remarkably prolonged, the whole preparation process is environmentally friendly, and the coating graphite piece is suitable for coating treatment of a large graphite base material.

This invention discloses a modified polysilazane, a two-component silicone sealant, and a method for preparing the same. The modified polysilazane is prepared through a nucleophilic substitution reaction of dimethyldichlorosilane, vinyltrichlorosilane, and ethylenediamine. The two-component silicone sealant prepared using the modified polysilazane of this invention significantly improves its hardness under sealed conditions without adversely affecting its curing and performance. Furthermore, it requires a small amount and is highly practical. The two-component silicone sealant prepared using the modified polysilazane of this invention exhibits high hardness retention under sealed conditions, significantly slows down the reversion phenomenon, and maintains good mechanical properties and adhesion even after curing at 90°C under sealed conditions. It also demonstrates excellent resistance to reversion under fully sealed conditions.

The invention discloses a high-performance silicon carbide coating embedding process, and relates to the technical field of static pressure graphite coating materials. The preparation method comprises the following steps: firstly, weighing SiC powder, Si powder and carbon powder according to a specific mass ratio, and carrying out ball milling and mixing to prepare embedding powder; the preparation method comprises the following steps: embedding a graphite matrix into embedding powder, and carrying out argon protection and temperature programming sintering to prepare a SiC coating modified graphite matrix; then preparing dendritic polysilazane steeping liquor containing azobenzene groups, putting the modified matrix into a vacuum steeping tank, carrying out ultraviolet irradiation assisted vacuum steeping and gradient drying, and then carrying out temperature programming curing, so as to obtain the composite coating modified graphite material. According to the process, the problems that a traditional embedding method has many coating defects and the mechanical property of a matrix is reduced are solved, through deep penetration repairing of photosensitive dendritic polysilazane, the coating density and the interface bonding strength are improved, and the obtained material has excellent mechanical and thermal properties and structural stability and meets the requirement of high-end working conditions.

To provide a polycarbosilazane making it possible to form a silicon-containing film having resistance to acid etching, and a composition comprising the polycarbosilazane.SOLUTION: The present invention provides a polycarbosilazane comprising repeating units of -[R1R2Si-(CH2)n]- and -(R3R4Si-NR5)- (where, R1, R2, R3 and R4 are each independently a single bond, hydrogen or C1-4 alkyl; R5 is independently a single bond or hydrogen; and n is 1-2, and a composition comprising the polycarbosilazane. The present invention also provides a method for forming a silicon-containing film, comprising coating the composition above a substrate and heating.SELECTED DRAWING: None

The present invention provides a method for coating a substrate comprising applying to the substrate: i. A solution A comprising at least a polysilazane and a solvent, ii. A solution B comprising at least a catalyst promoting crosslinking of the polysilazane and a solvent, where solution A and solution B are applied substantially separately onto the substrate and then mixed.

A compound containing a bis(azanylylidene) sulfonyl structure of formula (I) as a PKR agonist and / or USP9X inhibitor, which can be used for treating related diseases mediated and regulated by PKR and USP9X, wherein the related diseases comprise, but are not limited to: sickle-cell anemia, β-thalassemia, hereditary non-spherocytic hemolytic anemia, hemolytic anemia, hereditary spherocytosis, hereditary elliptocytosis, abetalipoproteinemia, paroxysmal nocturnal hemoglobinuria, acquired hemolytic anemia, congenital anemia, anemia of chronic diseases, colorectal cancer, kidney cancer, pancreatic cancer, breast cancer, lung cancer, esophageal cancer, melanoma, lymphoma, glioblastoma, or multiple myeloma. ;,

The invention provides a self-adaptive strong-plugging plugging agent for drilling fluid as well as a preparation method and application thereof, and belongs to the technical field of drilling engineering. The self-adaptive strong-plugging plugging agent for the drilling fluid is mainly prepared from the following raw materials in parts by weight: 100 parts of hydroxyl-terminated silicone rubber, 1 to 3 parts of a silazane compound KH-CL, 10 to 30 parts of alpha-methyl styrene, 3 to 5 parts of tetraethoxysilane, 10 to 30 parts of filler, 10 to 100 parts of iron oxide powder, 0.05 to 0.1 part of an azo initiator and 0.1 to 0.3 part of a tin catalyst. The density of the self-adaptive strong plugging plugging agent for the drilling fluid can be controlled to be 1.1-3g / cm < 3 >, and the self-adaptive strong plugging plugging agent can be applied to dispersion media with different densities, is tough and high-temperature-resistant, and can play an excellent role in leakage prevention and plugging under the dosage of 20-100g / L.

A method for producing a decorative part which comprises a visible side with a decorative layer and a mounting side with a substrate layer, wherein a polysilazane-containing composition is applied to the visible side of the decorative layer to form a cover layer and is subsequently cured. Also, a decorative part producible by the method.

The invention provides a low-dielectric photosensitive polyimide precursor, a photosensitive resin composition and a preparation method and application of the low-dielectric photosensitive polyimide precursor and the photosensitive resin composition. The low-dielectric photosensitive polyimide precursor is prepared by reacting a polymer obtained by reacting a dianhydride monomer and a diamine monomer with an organic silazane chain segment, the block polymer is formed by alternately arranging organic polyimide chain segments and organic silazane chain segments, and due to the structure, the dielectric constant of the material is effectively reduced, and meanwhile high adhesive force and high heat resistance of the material are ensured. The introduced silazane group can be converted into a SiO2 structure at a high temperature, so that the dielectric constant of the polyimide main body is further reduced, and the heat resistance is enhanced. In addition, the silazane groups can react with hydroxyl groups on the surface of the base material to generate silicon hydroxyl groups, so that the bonding strength between the polyimide and the base material is remarkably improved.

The invention discloses a silicon nitride composite material for a grading wheel and a preparation method of the silicon nitride composite material in the field of silicon nitride composites.A polysilazane structure with a main chain containing a benzene ring is formed through silane ammonolysis and subjected to coordination doping with metal ions and a crosslinking reaction of diisocyanate, the metal ions and an organic carbon chain structure are introduced, and the silicon nitride composite material for the grading wheel is obtained; the preparation method comprises the following steps: forming a three-dimensional cross-linked polysilazane precursor containing metal and organic carbon, carrying out molding and sintering treatment to form a compact biscuit, converting the organic carbon into SiCN in situ at a high temperature, carrying out synergistic growth on Si3N4-SiCN-metal nitride, and finally forming the high-density Si3N4-SiCN-metal nitride composite material, and fine grains and a low-defect structure are combined, the high-load requirement of components such as the grading wheel is met, the high hardness and self-lubricating property of SiCN and the hard spot effect of metal nitride are superposed, and the service life is remarkably prolonged.

The application discloses a graphite piece silicon carbide coating and a preparation method thereof in the technical field of inorganic non-metallic materials. The method comprises the following steps: firstly, surface polishing, cleaning and drying pretreatment are performed on the graphite piece; then, a solution containing phosphine azine functionalized silazane and boron-silicon calamine compound is sprayed on the pretreated graphite piece and dried and solidified to form a surface modification layer; finally, the surface modified graphite piece is placed in a chemical vapor deposition device to deposit a silicon carbide coating under specific temperature, pressure and atmosphere. The method effectively promotes the uniform nucleation and crystallization of the silicon carbide coating through unique surface modification treatment, significantly improves the compactness, uniformity and bonding force of the coating and the substrate. The obtained coated graphite piece has excellent thermal corrosion resistance, oxidation resistance and mechanical properties, the service life and service frequency in a semiconductor epitaxial device are significantly improved, the whole preparation process is environmentally friendly, and the method is suitable for coating treatment of large graphite substrates.

The application provides a synthesis process of hexamethyldisilazane. The synthesis process comprises the following steps: adding trimethylchlorosilane into liquid ammonia, then performing high-pressure stirring reaction to obtain a reaction liquid; performing layer separation, and performing rectification on the lower layer of the reaction liquid to obtain hexamethyldisilazane; performing pressure relief on the upper layer of the reaction liquid, and ammonia gas is generated after the liquid ammonia is vaporized, and ammonium chloride solid is precipitated; performing reduced-pressure drying on the ammonium chloride solid, desorbing the ammonia gas adsorbed on the ammonium chloride, and obtaining refined ammonium chloride. The reaction does not need to add any solvent, the reaction rate is adjusted by controlling the dropping speed of trimethylchlorosilane, and the generated by-product ammonium chloride is completely dissolved by controlling the addition amount of liquid ammonia, so that the mass and heat transfer effects of the reaction are ensured, the product conversion rate is improved, the reaction time is shortened, and the product is easy to separate. The method avoids the use of solvent, generates less waste liquid, is green and environmental protection, and is low in cost.

The application belongs to the technical field of protective coating, and particularly relates to a flexible chain graft modified polysilazane-based coating as well as a preparation method and application thereof. The flexible chain graft modified polysilazane-based coating comprises the following components in parts by weight: modified polysilazane 5-20 parts, active filler 5-15 parts, dispersion medium 60-80 parts, and auxiliary agent 0.1-0.5 parts; the modified polysilazane is prepared by grafting reaction of polysilazane and flexible high molecular compound. In the application, the flexible high molecular compound is grafted on the polysilazane, the modified flexible long chain can rotate freely, the coating is endowed with super-lubricating property, the brittleness of the coating is reduced, and the friction coefficient of the coating is reduced. The polysilazane takes Si-NH-Si bond as a repeating unit, can be easily combined with the -OH on the surface of a base material, and can form a covalent structure with metal atoms, so that the combination strength is high, the density after solidification is good, the hardness is high, and the wear resistance and corrosion resistance are strong.

The invention discloses a cubic boron nitride polycrystal and a preparation method thereof, and belongs to the technical field of superhard material preparation, the method comprises the following steps: mixing hexagonal boron nitride with two self-synthesized modified compounds silicon functionalized polyborazine and boric acid functionalized polysilazane, magnesium nitride and nano silicon powder, and carrying out ball milling drying and cold press molding to obtain a biscuit; the preparation method comprises the following steps: carrying out stepped heating heat treatment on a green body in a protective atmosphere to finish the stabilization of a precursor, and then carrying out reactive sintering under high-temperature and high-pressure conditions to finally prepare the cubic boron nitride polycrystal. The two modified compounds are converted into stable ceramic phases in heat treatment, and cooperate with a magnesium nitride catalyst, so that the conversion of hexagonal boron nitride to a cubic phase is remarkably promoted, and a grain boundary structure is optimized. The prepared cubic boron nitride polycrystal has the characteristics of high purity, good compactness, high hardness and excellent thermal stability.

The invention relates to the technical field of high polymer materials, and discloses ablation-resistant metal modified polyborosilazane resin as well as a preparation method and application thereof. The method comprises the following steps: (1) in an argon or nitrogen atmosphere, dropwise adding a part of hexamethyldisilazane into a solution containing metal chloride, and carrying out a first contact reaction to obtain an intermediate compound I; (2) in an argon or nitrogen atmosphere, dropwise adding the other part of hexamethyldisilazane into a mixed solution of boron trichloride and methyl dichlorosilane, and then mixing with the intermediate compound I to carry out a second contact reaction, so as to obtain an intermediate compound II; and (3) in an argon or nitrogen atmosphere, carrying out segmented heating curing treatment on the intermediate compound II to obtain the ablation-resistant metal modified polyborosilazane resin. According to the method, refractory metal elements are introduced into a polymerization system in situ in the form of a prefabricated metal silazane precursor, the polyborosilazane resin with uniformly distributed metal is successfully prepared, the high temperature resistance and ablation resistance of the material are remarkably improved, the controllability of the reaction process is high, and the industrial application prospect is good.

Provided is a method of manufacturing an alkoxysilane compound, the method capable of more effectively removing ammonia generated as a byproduct when the alkoxysilane compound is manufactured with a silazane-based compound by adding and reacting a silazane-based compound. The method includes: adding an alcohol to a silazane-based compound and allowing the alcohol to react with the silazane-based compound to manufacture a first mixture containing an alkoxysilane compound and ammonia; adding an acid having a pKa of 2-6.5 to the first mixture to prepare a second mixture containing the alkoxysilane compound and an ammonium salt; adding an aqueous solvent to the second mixture to dissolve the ammonium salt; and separating and removing the ammonium salt.

Provided is a gas barrier film which can be uniformly coated with a film and a polysilazane resin, and which has stress relaxation properties that do not impair workability. [Solution] A stress-relaxation gas barrier film characterized in that: the stress-relaxation gas barrier film is formed by alternately laminating one or more layers of a cured film layer and a stress-relaxation layer with each other; the cured coating layer is formed by curing a polysilazane composition containing a polysilazane compound represented by the following formula (1), the stress relaxation layer is formed by curing a silicone resin composition containing a linear organopolysiloxane represented by the following formula (A-1), and the film thickness of one layer is 0.1-15.0 [mu] m. ; .

The invention relates to the field of ethylene propylene diene monomer sealing elements, and discloses an EPDM sealing ring resistant to corrosion of a strong alkali electrolyte and a preparation method of the EPDM sealing ring. The EPDM sealing ring is prepared from the following raw materials in parts by weight: 40-60 parts of EPDM, 5-15 parts of a plasticizer, 25-40 parts of filler, 2-3 parts of an anticorrosive agent, 1-2 parts of a release agent, 1-2 parts of an anti-aging agent, 0.5-1 part of a vulcanizing aid and 0.5-1 part of a vulcanizing agent. The filler is prepared from white carbon black, argil, a silane coupling agent and a dispersing agent; the anti-corrosion agent is prepared from tetramethyl divinyl disilazane and SEBS (styrene-ethylene-butylene-styrene). The EPDM sealing ring prepared by the preparation process of mixing, calendering slicing and vulcanization forming is applied to energy storage equipment, has excellent strong alkaline electrolyte corrosion resistance, and does not have the problems of swelling and deformation after being used for a long time.

The invention provides a simple large-area water-oxygen barrier film as well as a preparation method and application thereof. The water and oxygen barrier film is provided with a SiOxCy / a-SiNx (O): H composite layer with a double-laminated structure, wherein the double-laminated structure is formed by converting organosilane into SiOxCy, converting polysilazane into a-SiNx (O): H, and stacking the SiOxCy and the a-SiNx (O): H. The flexible substrate or the electronic device is coated with the organosilane with the concentration larger than or equal to 20 wt% for curing and conversion, the exposure time of the device in air is shortened, the product yield is increased, the reaction condition is mild, the technology is simple, the device cannot be damaged in the preparation process, preparation of the large-area water-oxygen barrier film can be achieved, and the water-oxygen barrier film is suitable for large-scale production. The prepared water-oxygen barrier film has the advantages of high transparency, high flexibility, high barrier property and the like.