122results about How to "High strength retention" patented technology

The invention discloses a high-adhesive one-component deoximation type room-temperature vulcanized silicone rubber sealant comprising the following components from (A) to (F) in parts by weight: 100 parts of modified alpha, omega-dihydroxylpolydimethylsiloxane (A), 10-30 parts of dimethyl silicon oil (B), 7-12 parts of deketoxime crosslinking agent (C), 1-5 parts of silane coupling agent (D), 50-150 parts of reinforcing filler (E) and 0.1-1 part of catalyst (F). Compared with the traditional deoximation type sealant, the sealant has excellent adhesive property particularly for some substrates such as plastics, modified resin and the like which are difficultly adhered by using an organic silicon adhesive and can be widely applied to adhesion and sealing of industries such as electronics, automobiles, household appliances and the like. Modified polydimethylsiloxane is used as a basic polymer in deoximation type silicon rubber, so that the sealant has relatively proper surface drying time, provides more reasonable operation time and meets the production takt requirement under different working conditions; in addition, due to the adoption of the modified polydimethylsiloxane, the sealant has excellent waterproofness and is relatively high in strength retention rate under high temperature and high humidity conditions.

The invention relates to three-dimensional layered MXene electromagnetic shielding foam and a preparation method thereof and aims at solving the problems that an existing porous electromagnetic shielding material is low in absorbing and shielding effectiveness, poor in mechanical property and complicated in preparation process. According to the technical scheme, few-layer MXene dispersion liquid is prepared through wet chemical etching of an MAX phase; the dispersion liquid is directionally frozen through a bidirectional freezing process; and MXene aerogel is prepared through vacuum drying. The prepared MXene aerogel is of a layered structure, is long in range and ordered and has a good compression cycle characteristic, and the strength retention can reach over 60%. The total electromagnetic shielding effectiveness can reach 60-100dB; and the absorbing and shielding effectiveness can be adjusted through compressing the foam, so that the absorption-dominated electromagnetic shielding characteristic is achieved.

The invention discloses a low-dosage high-early-strength alkali-free liquid accelerator and a preparation method thereof. The alkali-free liquid accelerator is prepared from the following raw materials: 1, an alkali-free liquid accelerator; 50%-60% of modified aluminum sulfate, 2%-4% of a fluorine-aluminum complex solution, 3%-6% of an organic cosolvent, 1%-2% of a pH regulator, 0.5%-1.5% of an inorganic stabilizer, 0.3%-0.5% of a viscosity regulator, 4%-6% of a composite early strength agent and the balance of water, wherein the sum of the mass percentages of the components is 100%. The invention also provides a preparation method of the alkali-free liquid accelerator. The preparation process of the alkali-free liquid accelerator is simple; hydrofluoric acid-free process, alkali-free, chlorine-free, rust-free steel bar, non-polluting environment. Meanwhile, when the mixing amount of the alkali-free liquid accelerator is 5%-6%, the technical requirements of GB/T35159-2017 on the alkali-free accelerator can be met, the one-day compressive strength is larger than or equal to 13.0 MPa, and the alkali-free liquid accelerator has the advantages of being low in mixing amount, good in stability, high in early strength and large in later strength retention rate.

The invention relates to a process for producing spunlaced composite high-performance polyphenylene sulfide fiber filtering material, belongs to the fibrous raw material textile production technology field. The process uses polyphenylene sulfide fiber as raw material, has the following steps: processing raw material by checking, weighing, feeding, feeding into long certain, mixing cotton and fine loosing; layering and carding respectively by a first carding machine and a second carding machine; putting respectively into mesh placing machine for placing mesh; debatching, congruent, superposing and prewetting; spunlacing by a plurality of spunlacing machine, dewatering, drying and reeling. The advantages of the invention is that: the invention adopts polyphenylene sulfide high-performance fiber as raw material, the raw material is adapted to high efficient high speed carding production for its self physical and chemical properties, structure and adaptability to meshing and reinforcing process; improves spunlacing entanglement effect to fiber; improves the mechanical strength of spunlaced composite filtering material significantly, and ensures the end product to achieve excellent mechanical properties, filtering quality and chemical resistance property.

Present invention provides an electrolytic copper foil having a high normal tensile strength and a resistance to the lowering of the tensile strength after thermal treatment. An electrolytic copper foil having a normal tensile strength of 500-750 MPa and a tensile strength after heating at 400° C. for one hour of at least 350 MPa.

The present invention relates to the field of materials, and discloses an artificial stone material and a preparation method and use thereof, and the artificial stone material comprises the following components by weight: 20 to 60 parts of resin, 10 to 30 parts of a filling material and 6 to 10 parts of hollow glass beads. The hollow glass beads as a lightweight filler are added into the artificial stone formula, on the one hand, the density of the artificial stone formula is reduced, so that the artificial stone material is lighter in weight, on the other hand, due to good interface compatibility of the hollow glass beads and the resin and other filler relative to other lightweight materials, the artificial stone material is higher in strength retention rate, the artificial stone material is easier to polish, a product prepared from the artificial stone material has contamination-resistant surface appearance with good chemical resistance, a surface coating or gel coat is not needed, and artificial stone products are easy to design.

The invention provides an alkali-free liquid quick-setting agent, a preparation method and applications thereof, wherein the raw materials comprise, by mass, 45-55% of aluminum sulfate, 5-10% of nanometer alumina, 5-10% of hydrofluoric acid, 3-7% of a solubilizing component, 2-6% of fluorosilicate, 1-4% of an early strength component, 0.5-1% of a stabilizer, and 20-32% of water. According to the present invention, the aluminum sulfate is used as the main raw material, and is matched with the nanometer alumina, the hydrofluoric acid, the solubilizing component, the fluorosilicate, the early strong component and the stabilizer, such that the obtained alkali-free liquid quick-setting agent has characteristics of good setting acceleration effect, long-term stability and low rebound rate, can substantially improve the earth strength of concrete, and can have high strength retention rate in late strength, wherein various performance indexes can meet the requirements on the first-class quick-setting agent in standard JC477-2005 Flash setting admixtures for shotcrete at a dosage of 7%.

A high-temperature brazing filler metal for soldering C/C and C/SiC composite materials and preparation methods thereof relate to high-temperature soldering materials and preparation methods of the high-temperature soldering materials and mainly solve the problems of low high-temperature strength retention rate and poor performance of soldering joints in existing high-temperature solders for soldering the C/C and C/SiC composite materials. The high-temperature brazing filler metal for soldering the C/C and C/SiC composite materials is made from Ni and Zr or ZrH2. A method I comprises 1) weighing Ni and Zr or ZrH2, 2) performing smelting to obtain an alloy ingot and 3) performing foil fabrication. A method II comprises 1) weighing Ni and Zr or ZrH2, 2) performing ball milling to obtain a mixed powder and 3) pressing the mixed power to obtain foils and washing and drying the foils. The high-temperature brazing filler metal for soldering the C/C and C/SiC composite materials can provide a good wettability for the C/C and C/SiC composite materials and can mainly be formed into two structures during a soldering process, thereby guaranteeing the mechanical performance of the soldering joints. The components of the high-temperature brazing filler metal for soldering C/C and C/Sic composite materials do not contain precious metals, so that the cost is low; and the melting point of the component Zr is 1852 DEG C, so that the soldering joints can be guaranteed to have a high strength retention rate at 600 DEG C.

The invention provides a method for degradation of a composite material by directional bond breaking and recovery of fibers from the composite material. The method comprises the following steps that (1) the composite material is cut into composite material blocks with the target size for standby application; (2) the composite material blocks, solvents, metal salts, ligands, pH regulators and oxidants are mixed evenly, and then heated, the composite material blocks are naturally cooled to the room temperature after being completely degraded, and then high-speed centrifugal separation is conducted to obtain crude fiber products; and (3) the crude fiber products are washed and dried, and finally fiber fine products are obtained. According to the method, through the hot solvent effect, unsaturated complexation and weak complexation, the solvents, the metal salts, the ligands, the pH regulators, the oxidants and the composite material are mixed, and then heated, directional bond breaking degradation of resin is achieved, finally the fibers with little surface resin residue, basically no defect and the fiber strength retention rate up to 97.1% are obtained, and the degradation rate of the resin is as high as 100%.

The invention discloses a coating material for surface modification of PBO (Poly-p-phenylene Benzobisoxazole) fibers. The coating material is prepared from an ultraviolet absorbent, heptadecafluorodecyl trimethoxysilane, cycloaliphatic epoxy resin, a curing agent and an organic solvent. The invention further provides a method for carrying out surface modification on the PBO fibers and surface modified PBO fibers prepared through the method. Furthermore, the invention further provides an extra-high voltage live working tool soft material which is prepared by braiding and twisting the surface modified PBO fibers. The treated PBO fibers overcome the disadvantage of no ageing resistance, have very good insulating performance and can be widely applied to insulating ropes for extra-high voltage live working.

The invention relates to a production process for a polytetrafluoroethylene (PTFE) aqua tex composite high-temperature tail gas filter material, which belongs to the technical field of spinning filter materials. Polytetrafluoroethylene fibers and glass fiber base fabrics are adopted as raw materials. Firstly, the polytetrafluoroethylene fibers are detected and weighted, then sequentially fed into a long curtain, a horizontal opener, a large-cabinet and a fine opener, combed by a combing machine 1 and a combing machine 2 in layering mode, and respectively fed into a cross lapping machine 1 and a cross lapping machine 2 to be lapped. The glass fiber base fabrics are laminated between the raw materials sent out of the cross lapping machine 1 and the cross lapping machine 2 to be coincided and then sequentially is processed by a prewetting process, an aqua tex process, a dewatering process, a drying process and a coiling process. The PTFE aqua tex composite high-temperature tail gas filter material is strong in mechanical performance, filter performance, high temperature resistance and chemical corrosion resistance and stable in size.

Disclosed is a method of producing a polyethylene terephthalate-based polyester fiber, including spinning polyethylene terephthalate based polyester to produce an undrawn yarn with an intrinsic viscosity of 0.83 or more and a density of 1.338 g/cm³ or more, multi-stage drawing the undrawn yarn, heat-setting the drawn yarn, relaxing the heat-set yarn, and winding the relaxed yarn to produce the resulting drawn yarn with an intrinsic viscosity of 0.83 or more and a density of 1.38 to 1.3865 g/cm³. Compared to a prior polyester yarn with high modulus and low shrinkage, produced according to conventional melt-spinning and drawing processes, an industrial polyester yarn with high modulus and low shrinkage according to the present invention contributes to significantly improving strength retention (tenacity of a dip cord/tenacity of a grey yarn) of the dip cord, produced by treating the polyester yarn of the present invention with an adhesive (RFL) and subsequently heat-treating the RFL-treated polyester yarn. Therefore, the polyester multifilament yarn according to the present invention is useful as a tire cord.

The invention relates to a method for manufacturing a ceramic matrix composite boron nitride interface coating, in particular to manufacturing of boron nitride coatings on a fiber surface and a substrate surface and belongs to the technical field of ceramic matrix composite toughness improvement. According to the method, a single component NH3BH3 containing B and N at the same time is selected as a precursor of a BN interface, the precursor is free of toxin and pollution, unlikely to burn or explode and capable of easily forming BN at the stoichiometric ratio of B:N=1:1, it is guaranteed that the manufactured BN is good in stoichiometric ratio, the problem that B and N in a double-component precursor are disproportionate is avoided, and no corrosive gas is generated in the manufacturing process. The method can be used for manufacturing the coating at the reaction temperature from 400 DEG C to 900 DEG C through a low-temperature chemical vapor deposition method, the temperature from 700 DEG C to 900 DEG C is preferred to increase the yield of BN, and the content of the obtained deposition product BN is over 97%. The strength retention rate of fibers can be increased as much as possible through low-temperature deposition, the strength retention rate is over 90% after deposition, and the strength retention rate is over 70% after high-temperature thermal treatment.