11results about How to "Solve the brittleness problem" patented technology

The invention discloses heat-resistant modified epoxy resin and a preparation method thereof, and belongs to the technical field of high polymer materials. The heat-resistant modified epoxy resin is prepared from the following components in parts by mass: 45 to 55 parts of matrix epoxy resin, 10 to 20 parts of methyl phenyl silicone resin, 8 to 12 parts of nano silicon dioxide, 0.8 to 2.0 parts of a silane coupling agent, 6 to 10 parts of a curing agent, 0.3 to 0.8 part of an accelerant, 15 to 30 parts of silica fume powder and 0.5 to 1.2 parts of an antioxidant. By introducing components such as methyl phenyl silicone resin and nano silicon dioxide with a specific particle size, and combining the synergistic effect of the silane coupling agent, the heat resistance of the epoxy resin is effectively improved; the antioxidant with a specific structure is used, and the performance retention rate of the modified epoxy resin under a thermo-oxidative aging condition is remarkably improved, so that the service life of the material is prolonged, and the long-term stability of the material in a high-temperature environment is enhanced.

This invention relates to the field of flame-retardant polymer materials technology, specifically a process for preparing high-temperature flame-retardant PC / ABS alloy resin modified with maleic anhydride-grafted POE. The modification of PC / ABS alloys to achieve high heat resistance and halogen-free flame retardancy often presents the technical challenge of synergistically improving heat resistance, toughness, and flame retardancy. This invention employs a synergistically optimized preparation process. A specific step-feeding melt-blending extrusion strategy is used, where PC and heat-resistant ABS, with maleic anhydride-grafted POE as the core compatibilizer, are melt-blended. After sufficient plasticization and the initial formation of a stable phase structure, a heat-sensitive halogen-free phosphorus-based flame retardant and an anti-dripping agent are injected. This avoids premature decomposition and failure of the flame retardant at high temperatures, ensures sufficient reaction of POE-g-MAH at the PC / ABS phase interface, optimizes the dispersed phase morphology, enhances the low-temperature impact toughness and stress cracking resistance of the PC / ABS alloy resin, and solves the material brittleness problem caused by the introduction of flame retardants.

This application discloses an adhesive for semiconductor packaging and its preparation method. The adhesive comprises the following raw materials in parts by weight: 100 parts epoxy resin, 1-5 parts curing agent, 0.1-1 parts accelerator, 10-20 parts silicone-modified polyurethane, 5-10 parts thermally conductive filler, 3-6 parts thickener, and 20-30 parts diluent. The silicone-modified polyurethane is prepared by hydrosilylation of an alkenyl polyurethane prepolymer and a siloxane compound in a mass ratio of 10:0.3-1. The alkenyl polyurethane prepolymer is obtained by polymerization of raw materials containing polyether polyol, alkenyl polyethylene glycol ether, and isocyanate. This application, by adding silicone polyurethane to the epoxy resin system, introduces flexible segments and forms an interpenetrating network structure, effectively compensating for the loss of flexibility in the epoxy adhesive layer and effectively solving the problem of flexibility degradation of epoxy resin encapsulants after filling with thermally conductive fillers.

The application discloses a kind of cyclic olefin multi-block copolymer and its preparation method and application, it includes the following steps: S1, solvent, cocatalyst, cyclic olefin, chain shuttle agent are mixed to obtain mixed solution;Add olefin again;S2, catalyst I and catalyst II are added in step S1 and carry out polymerization reaction, post-processing is obtained cyclic olefin multi-block copolymer;Wherein, the structural formula of catalyst I and catalyst II are as follows:Wherein, M is titanium, zirconium or hafnium;X is halogen, C 1～10 Alkyl of C 1～10 Alkoxy or C 1～10 Alkylamine;R1 And R2 It is independently selected from C 1～10 Aliphatic group, substituted or unsubstituted C 6～15 Aromatic group;R3, R4, R5 And R6 Selected from C 1～10 Alkyl or C 6～15 Aromatic group.The cyclic olefin multi-block copolymer prepared by selecting specific structure catalyst I and catalyst II has cyclic olefin / olefin chain soft segment (low T g1 ) with low insertion rate and cyclic olefin / olefin chain hard segment (high T g2 ) with high insertion rate;The obtained material can solve the brittleness problem of COC plastic, and also can obtain COC elastomer.

The invention provides a cycloolefin block copolymer and a preparation method thereof, and relates to the technical field of block copolymers, the preparation method comprises the following steps: sequentially adding monocycloolefin, cycloolefin containing a rigid structure, an inert solvent, a molecular weight regulator and a cocatalyst into a reaction kettle, and mixing to obtain a mixed solution, simultaneously adding a solution of a catalyst I and a catalyst II in an inert solvent, and carrying out ring-opening polymerization reaction; and after the reaction is finished, removing the catalyst I and the catalyst II, filtering to take supernatant liquid, introducing a hydrogen source into the supernatant liquid, adding a hydrogenation catalyst, carrying out hydrogenation reaction, and after the reaction is finished, filtering and separating to obtain the cycloolefin block copolymer. The cycloolefin block copolymer prepared by the invention has better thermal stability, higher elongation at break, higher glass transition temperature, good transparency and excellent processability.

The application discloses a strontium ferrite / polyether ether ketone composite magnet and a preparation method and application thereof, and belongs to the technical field of permanent magnet materials.The strontium ferrite / polyether ether ketone composite magnet comprises, in mass fraction, near Curie point magnetic field heat-treated strontium ferrite magnetic powder 84-95 parts, polyether ether ketone 5-15 parts, silane coupling agent 0.5-1.5 parts and lubricant 0.3-0.7 parts.The application adopts the above strontium ferrite / polyether ether ketone composite magnet and the preparation method and application thereof, realizes the synergistic improvement of magnetic performance, mechanical strength and heat resistance through intrinsic magnetic domain structure optimization, interface bonding strengthening and high densification structure design, and can meet the application requirements under the working conditions of high temperature, high reliability and high strength.

This invention relates to the field of waterborne coatings technology, specifically to a waterborne industrial anti-rust paint for steel components and its preparation method. This invention overcomes the problems of insufficient anti-rust performance and weak mechanical properties of existing waterborne industrial anti-rust paints. This invention achieves a synergistic effect of chemical anchoring and physical shielding by simultaneously bonding phosphate groups and graphene to the epoxy resin molecular chain; it significantly improves the mechanical properties of the coating film by using an organosilane coupling agent-modified waterborne polyamide curing agent to form an organic-inorganic interpenetrating network structure; it avoids the brittleness problem of pure epoxy systems by introducing a core-shell structured self-crosslinking acrylate emulsion, and the formed interpenetrating polymer network structure further enhances the density of the coating film; it forms an active-passive electrochemical synergistic protection with zinc-aluminum phosphate composite pigments by adding functionalized conductive polymer aqueous dispersions; and it enhances anti-rust performance by compounding zinc-aluminum phosphate composite pigments with glass powder.

The invention provides SiC-ZrC ceramic fiber aerogel with high flexibility and low thermal conductivity and a preparation method of the SiC-ZrC ceramic fiber aerogel, and relates to the field of aerogel materials. The method comprises the following steps: preparing a spinning solution containing a silicon precursor, a zirconium precursor and polyvinylpyrrolidone, and carrying out electrostatic spinning, pre-oxidation and heat treatment to finish ceramic treatment of SiC and ZrC fibers in one step, so as to prepare SiC-ZrC ceramic fiber aerogel with a three-dimensional fiber network structure; the diameter of fibers in the aerogel is nanoscale, and the microstructure comprises a SiC nanofiber matrix and ZrC nanoparticles which are uniformly distributed. The SiC-ZrC ceramic fiber aerogel integrating excellent mechanical property and heat insulation property is finally prepared by regulating and controlling the content of the zirconium precursor, spinning parameters and heat treatment parameters and accurately controlling the fiber morphology and aerogel performance; the method is simple in process, good in controllability, high in repeatability and suitable for large-scale production.

The application discloses a heat-insulating light-shielding plate with variable light transmittance and a preparation method thereof. The structure of the heat-insulating light-shielding plate is organic glass layer-aerogel layer-organic glass layer, wherein the aerogel layer is a sandwich structure, the inside of which is a first wet gel prepared from orthosilicate, and the outside of which is a second wet gel prepared from methyl triethoxysilane; and the aerogel layer and the organic glass layer are coated with methyl methacrylate. The application composites the aerogel and the organic glass, mutually supplements in the case of not affecting the respective performances, solves the problem that the heat insulation of the light-shielding plate is poor, and can adjust the light transmittance according to the environmental temperature, further assists heat insulation, and has a wide application prospect.

The invention discloses low-iron-loss non-oriented electrical steel for an electric vehicle motor and a processing method thereof, and relates to the technical field of non-oriented electrical steel, and the low-iron-loss non-oriented electrical steel comprises the following components in percentage by weight: 3.0-3.8% of Si, 0.25-0.35% of Als (% of Si), 0.40-0.55% of Mn (% of Si), less than or equal to 0.1% of P, less than or equal to 0.2% of N, less than or equal to 0.003% of C, less than or equal to 0.004% of C + Ti, less than or equal to 0.02% of S, and the balance of Fe and inevitable impurity elements. Through the gradient structure design of fine equiaxed grains on the surface layer and thick equiaxed grains on the core part, the high and low frequency working conditions of the electric vehicle driving motor are accurately matched. Under low frequency, the magnetic hysteresis loss is obviously reduced by coarse grains at the core part; under high frequency, surface layer fine grains improve resistivity by utilizing skin effect, eddy current loss is effectively inhibited, iron loss P1.5 / 50 is less than or equal to 2.35 W / kg, P1.0 / 400 is less than or equal to 14.00 W / kg, and P1.0 / 1000 is less than or equal to 38.0 W / kg, a cold rolling process adopts different-diameter rolling core design, and a gradient energy storage and grain structure can be formed through dynamic matching of the roller diameter of an upper working roller and the reduction rate of the current pass without additional nitriding and other complex processes.

This invention belongs to the technical field of covalent organic framework membrane materials, and provides a covalent organic framework / polyethersulfone hybrid matrix membrane, its preparation method, and its application. The method includes the following steps: mixing polyethersulfone, a solvent, and trialdehyde-based resorcinol to obtain a trialdehyde-based resorcinol solution; coating the trialdehyde-based resorcinol solution onto a glass fiber filter membrane to obtain a trialdehyde-based resorcinol / polyethersulfone membrane; mixing p-phenylenediamine, a catalyst, and water to obtain a p-phenylenediamine solution; and immersing the trialdehyde-based resorcinol / polyethersulfone membrane in the p-phenylenediamine solution to react, thereby obtaining the covalent organic framework / polyethersulfone hybrid matrix membrane. The preparation method of this invention is mild, and the resulting membrane is uniform and stable, fully combining the high flux of the polymer and the CO2 suppression capabilities of the covalent organic framework. 2 The advantages of strong adsorption separation significantly improve the H2O performance of covalent organic framework / polyethersulfone hybrid matrix membranes. 2 Flux and H 2 / CO 2 Selectivity.