32 results about "Low shrinkage" patented technology

The present invention provides a thermosetting resin composition for electromagnetic wave shielding, a bulk molding compound, and a molded product thereof, which are excellent in fluidity, injection molding property, compression molding property, and in which a molded product excellent in electromagnetic wave shielding property can be obtained. The thermosetting resin composition for electromagnetic wave shielding is characterized by containing a thermosetting resin (A) containing an unsaturated polyester resin (a1) and a vinyl ester resin (a2), a low shrinkage agent (B), a thickening agent (C) containing acrylic resin particles (c1) and magnesium oxide (c2), a thermally conductive filler (D), and a reinforcing material (E).

This invention discloses a floor repair agent and its preparation method, belonging to the field of building materials technology. The repair agent comprises a modified resin component, a curing agent component, a modified composite functional filler, and composite additives. The modified resin is a composite system of silane coupling agent-modified epoxy resin and terminally hydroxylated polyurethane. The modified composite filler consists of modified nano-silica, passivated quartz sand, and hydroxylated recycled polyurethane rigid foam powder. The composite additives include a compound toughening agent and composite modified polypropylene fibers. During preparation, each component undergoes targeted modification pretreatment, followed by temperature-controlled stirring and step-by-step mixing to obtain the finished product. This invention solves the problems of poor resin compatibility, weak filler bonding force, and easy cracking and debonding in existing repair agents. The product has high bonding strength, low shrinkage, wear resistance, and impact resistance. It can be used stably in environments ranging from -30℃ to 80℃, is environmentally friendly and odorless, and is easy to apply. It combines performance and cost advantages, and is suitable for long-term repair of various floor types and heavy-duty, high- and low-temperature conditions.

This invention discloses a high-elasticity modulus concrete and its preparation method. The high-elasticity modulus concrete comprises, by weight, cementitious materials: volcanic rock: river sand: water: water-reducing agent in a ratio of 575:990:755:115:(20-22). The cementitious materials, by weight, comprise: cement: fly ash: silica fume in a ratio of (375-435):85:55. This invention utilizes volcanic rock as coarse aggregate to construct a rigid skeleton, and incorporates cementitious materials to leverage their synergistic physical filling and volcanic ash effect, optimizing the matrix density and interfacial transition zone structure. Combined with ultrasonic-assisted mixing, it achieves uniform dispersion and efficient hydration of fine materials. This concrete exhibits high compressive strength and high elastic modulus, demonstrates low shrinkage and creep characteristics, good volume stability, and excellent durability. It is suitable for high-rise and super high-rise buildings and large-span structural engineering, significantly improving structural stiffness, saving building materials, and increasing usable space utilization.

This invention discloses a method for preparing superhydrophobic aerogels under ambient pressure based on framework regulation and its application. The invention involves a multi-component composite of carboxymethyl cellulose, aramid fiber, carboxylated nitrile rubber, melamine-formaldehyde resin, modified montmorillonite, hydrophobic silica, and an organosilicon waterproofing agent. A vertical pore template is constructed through directional freezing, followed by gradient solvent displacement and ambient pressure drying to finally solidify the superhydrophobic-superoleophilic aerogel. This invention successfully overcomes the core challenge of structural collapse caused by capillary forces during ambient pressure drying through the synergistic enhancement of the organic-inorganic hybrid framework and surface energy regulation, achieving a balance between low shrinkage, high porosity, and stable superwetting properties. The aerogel of this invention possesses excellent mechanical strength and elasticity, and its functionality can be expanded by introducing photothermal fillers. The process equipment is simple and energy-efficient, providing an economical and feasible technical path for the large-scale preparation of high-performance superhydrophobic aerogels.

This invention belongs to the field of electronic materials technology, specifically relating to a cofferdam filler adhesive and its preparation method. It includes two components, A and B: Component A is a thixotropic cofferdam adhesive, comprising epoxy resin, a latent curing agent, a composite thixotropic agent, a composite inorganic filler, an interface compatibilizer, a coupling agent, and a dispersant; Component B is a flowable filler adhesive, comprising epoxy resin, an anhydride curing agent, a curing accelerator, an inorganic filler, a coupling agent, a wetting and dispersing agent, a stress absorber, and a surface tension modifier. The prepared cofferdam adhesive exhibits high viscosity, high thixotropy, high Tg, and low shrinkage, while the filler adhesive has low viscosity, low thixotropy, good flowability, low shrinkage, and high Tg. The two products have similar coefficients of thermal expansion and good compatibility.

This invention relates to the field of TPE production and processing technology, and provides a method for preparing and applying low-shrinkage TPE car floor mats, comprising the following steps: Step 1, adding SBS, maleic anhydride, styrene, and AIBN to a mixing container in proportion, using toluene as a solvent, heating to 60°C, magnetically stirring for 6-8 hours, concentrating after the reaction is complete, adding methanol for precipitation, then filtering and drying to obtain the SBS copolymer; Step 2, adding the SBS copolymer, rare earth oxides, calcium carbonate, nano-silica, bentonite, deodorizing agent, and antioxidant in proportion to a high-speed mixer and mixing for 15-20 minutes, then feeding into a twin-screw extruder, melting at 180°C-220°C, extruding, and cooling to obtain low-shrinkage TPE. The method for preparing and applying low-shrinkage TPE car floor mats provided by this invention results in a material with not only low shrinkage but also good stability and no odor, showing broad application prospects for car floor mats.

This invention provides an epoxy resin composition, its preparation method, and its application. The epoxy resin composition, by mass fraction, comprises component A and component B; component A comprises: 5-12% epoxy resin, 0.4-2.5% diluent, 40-60% first filler, 0.1-0.5% first coupling agent, 0.1-0.5% first dispersant, and 0.1-0.5% carbon black; component B comprises: 2.5-5% curing agent, 25-40% second filler, 0.1-0.3% second coupling agent, and 0.1-0.3% second dispersant. This invention, by adjusting the proportions of the various substances and using a novel epoxy resin structure and a high-performance diluent, achieves low viscosity, low shrinkage, low modulus, and high resistance to damp heat. In the encapsulation of power module electronic components, motors, capacitors, sensors, transformers, etc., it exhibits excellent potting operability, anti-delamination, and reliability.

Provided are: a thermosetting resin composition which has excellent fluidity, injection moldability, and compression moldability, and which is capable of obtaining a molded article having excellent thermal conductivity; a bulk molding compound; and a molded article thereof. The thermosetting resin composition is characterized by containing a thermosetting resin (A) containing an unsaturated polyester resin (a1) and a vinyl ester resin (a2), a low shrinkage agent (B), a thickener (C) containing acrylic resin particles (c1) and magnesium oxide (c2), a thermally conductive filler (D) containing a thermally conductive filler (D), and a reinforcing material (E). The thermally conductive filler (D) contains a thermally conductive filler (d1) having an average particle diameter of 100 [mu] m or more and 500 [mu] m or less and a thermally conductive filler (d2) having an average particle diameter of 10 [mu] m or more and less than 100 [mu] m.

The application discloses a large marine engine cylinder sleeve low shrinkage casting process and belongs to the casting technical field.The large marine engine cylinder sleeve low shrinkage casting process has the following preparation steps: (1) smelting; (2) vermicular treatment; (3) teeming and inoculation; (4) pouring; (5) cooling; and (6) cleaning and sand dropping to obtain the cylinder sleeve, wherein the raw materials for smelting include pig iron, scrap steel, recycled iron, vanadium iron and composite boron nitride; the vermicular agent for vermicular treatment is a rare earth vermicular agent; the proportion of lanthanum in the total amount of the rare earth vermicular agent is 24-37%; the adding amount of the rare earth vermicular agent is 0.6-1%; and the inoculant is 75% Si-Fe inoculant.The large marine engine cylinder sleeve prepared by the application has good wear resistance, low shrinkage, and good mechanical properties.

The application relates to the technical field of fiber materials, and provides a fiber material reinforcing method considering high tearability and high air permeability. The reinforcing method comprises the following steps: mixing and treating main body web forming fibers, high-strength low-shrinkage fibers, heat-shrinkable fibers and low-melting-point bonding components to obtain a mixed fiber material; performing forming treatment on the mixed fiber material to obtain a preformed fiber web; performing segmented heat treatment on the preformed fiber web, and performing selective heat stabilization treatment on the low-melting-point bonding components to obtain a fiber material. According to the application, the high-strength low-shrinkage fibers, the heat-shrinkable fibers and the low-melting-point bonding components are introduced into the base pore network formed by the main body web forming fibers, and the segmented heat treatment and the selective heat stabilization treatment are combined, so that the fiber network is subjected to controlled reconstruction under the action of heat, and heat-stable nodes are formed at local key connection positions, the internal through-pore structure of the fiber material is maintained, and the tear resistance and the structural stability of the fiber network are improved.

This invention discloses a dental composite resin with high mechanical strength and low shrinkage stress, its preparation, and its application. The composite resin, by mass percentage, consists of 50-80% inorganic powder and 20-50% resin system. The resin system comprises 2.5-43.2% high-viscosity monomers containing rigid segments, 5-48.6% low-viscosity prepolymer, 20-45% low-viscosity monomers, 9.8-49.8% mercapto-acetylene resin system, and 0.4-2% photoinitiator system. The high mechanical strength and low shrinkage stress composite resin of this invention exhibits low shrinkage stress and superior mechanical strength, showing promising application prospects in dental materials.

The application discloses a kind of high toughness low shrinkage concrete and preparation method thereof.The concrete is composed of cementitious material system, aggregate, modified fiber and auxiliary material;Cementitious material system includes cement, mixed mineral admixture and micro-expansion component, mixed mineral admixture is metakaolin and zeolite powder compound, and micro-expansion component is calcium sulphoaluminate mineral powder;Modified fiber includes basalt fiber surface modified by silane coupling agent and polyvinyl alcohol fiber compound system.The preparation method of the application includes fiber modification, mixed mineral admixture activation, stirring, pouring molding and maintenance and the like steps.The concrete of the application has low shrinkage, high toughness and excellent mechanical properties, and can be widely used in building structure, bridge engineering and prefabricated component field.

This invention discloses an anti-aging power metering box cabinet material, relating to the field of organic materials technology. The anti-aging power metering box cabinet material comprises the following raw materials by weight percentage: 25%-35% unsaturated polyester resin, 11%-15% low-shrinkage agent, 0.5%-2% initiator, 2.5-8% additives, 35%-50% organic composite filler, and 15%-25% modified chopped glass fiber. This application adds the prepared modified chopped glass fiber to the unsaturated polyester resin, along with the remaining additives required for preparing the electrical cabinet material, to obtain the cabinet material for use in power metering boxes. The power metering box cabinet material prepared in this application has advantages such as excellent mechanical properties, stable environmental aging resistance, low dielectric loss, and low dielectric constant.

This invention discloses a low-shrinkage, highly corrosion-resistant glass flake coating and its preparation method. The coating comprises a main agent, which is mainly prepared from the following components in the following weight ratios: 45-65 parts epoxy vinyl unsaturated polyester resin, 20-30 parts glass flakes, 1-3 parts fluorinated toughening modifier, 0.1-2 parts dispersant, 0.1-1 part defoamer, 0.1-3 parts thixotropic agent, 1-15 parts unsaturated polyester reactive diluent, and 1-15 parts acid and alkali resistant powder; the epoxy vinyl unsaturated polyester resin includes phenolic epoxy vinyl unsaturated polyester resin. The coating of this invention exhibits excellent heat resistance and structural stability, and demonstrates superior toughness and acid resistance at high temperatures. It effectively reduces volume shrinkage during curing, achieving low shrinkage performance and extending the service life of the coating.

This application relates to a method for preparing a toughened, low-shrinkage unsaturated polyester resin bulk molding compound. The bulk molding compound is extruded using a screw extruder. The screw extruder includes a frame, an extrusion module, and an extruder head. The extruder head is equipped with a filter structure, which includes a filter screen with a plurality of filter holes and a drive component. The filter screen is installed inside the extruder head and is rotatable. The drive component includes a toothed ring fixed to the filter screen and a drive gear driven by a motor installed outside the extruder head. One side of the toothed ring is exposed outside the extruder head, and the drive gear meshes with the toothed ring. This application uses a drive gear to drive the rotation of the toothed ring, thereby causing the filter screen to rotate inside the extruder head. This solves the problem of a fluid dynamic "dead zone" easily forming in the contact area between the filter screen edge and the inner wall of the extruder when using a fixed filter screen structure, reducing the possibility of scorching caused by the retention of high-viscosity thermosetting materials.

The invention relates to a polypropylene composition comprising a heterophasic propylene copolymer wherein the heterophasic propylene copolymer consists of: a propylene homopolymer matrix in an amount from 71 to 92 wt%, preferably from 78 to 89 wt%, more preferably from 84 to 89 wt% based on the heterophasic propylene copolymer, an ethylene-propylene copolymer in an amount from 8 to 29 wt%, preferably from 10 to 29, more preferably 11 to 29 wt%, even more preferably from 11 to 22 wt%, even more preferably from 11 to 16 wt% based on the heterophasic propylene copolymer and wherein t the amount of units derived from ethylene based on the ethylene-propylene copolymer is between 42 and 60 wt%, more preferably 42 and 55 wt%, more preferably 45 and 51 wt% and wherein the polypropylene composition has • a melt flow rate (MFR) in the range from 0.50 to 120 dg / min, wherein the melt flow rate is determined using ISO1133-1:2011 using 2.16kg at 230°C and • a ratio of methylene sequence n>5 over the amount of units derived from ethylene based on the ethylene-propylene copolymer of less than 0.30.

The application relates to the technical field of concrete construction, and particularly discloses a mass concrete construction method, which comprises the following steps: S1, preparing low-waterization-heat low-shrinkage high-durability mass concrete; S2, transporting, pouring and vibrating the concrete; when the concrete is poured, a pipe is first moistened by hot water and mortar with a temperature not lower than 15 DEG C before pumping in winter construction, and the concrete pumping pipeline is wrapped with reflective heat preservation materials in summer construction, so that the temperature difference between the inside and outside of the pumping pipeline is between 1-1.5 DEG C; the temperature of the mass concrete when entering a mold in a high-temperature environment in summer is controlled to be less than 30 DEG C, and the temperature of the mass concrete when entering the mold in a cold environment in winter is controlled to be higher than 10 DEG C; and S3, concrete curing; in the concrete curing process, the temperature difference between the center and the surface of the concrete during summer curing is controlled to be not greater than 25 DEG C. The application has the characteristics of reducing the concrete shrinkage and cracking risk.

The application discloses a preparation method of basalt fiber reinforced thermoplastic resin intermediate material and belongs to the technical field of composite material preparation. The basalt fiber and thermoplastic resin fiber are used as raw materials, and the preparation method comprises the following steps: fiber opening, plasma and silane coupling agent composite surface modification, weighing type closed loop quantitative feeding, multi-stage carding cross-laying, constant tension needle punching forming, three-zone independent temperature control melting impregnation, gradient cooling shaping and online detection closed loop regulation. The mixed woven felt intermediate material is prepared. The interface modification is used to improve the bonding force between the fiber and the resin. The precise feeding and constant needle punching are used to ensure the uniformity of the felt blank. The partition temperature control, deflection compensation, pressure and gradient cooling are used to realize sufficient impregnation and size stability. The method can be suitable for various thermoplastic systems such as PP, PA6 and low shrinkage PET, can meet the continuous and large-scale production requirements, and solves the problems of poor interface bonding, uneven impregnation, insufficient size stability and low consistency of mass production in the traditional process.

Disclosed is a magnesium phosphate-based cement grouting material, a preparation method therefor and use thereof. Raw materials of the magnesium phosphate-based cement grouting material include a component A and a component B; the component A includes the following raw materials in parts by weight: 140-200 parts of calcined magnesium oxide, 0-30 parts of bentonite, 0.2-0.5 part of hydroxypropyl methyl cellulose, 1-10 parts of additive and 70-140 parts of water; the component B includes the following raw materials in parts by weight: 70-100 parts of first dihydric phosphate, 20-50 parts of pretreated polymer water-absorbent resin, 0.5-2 parts of sodium polyacrylate and 30-70 parts of water. The magnesium phosphate-based cement grouting material has the advantages of low shrinkage, short and adjustable setting time, high compressive strength, simple construction, low cost, environmental friendliness, good grout injectivity, good resistance to water dispersibility and good durability in a long-term soaking environment.

The present application belongs to the technical field of polymer materials, and particularly relates to a low-shrinkage high-transmittance polypropylene composition and a preparation method thereof. The composition is composed of the following raw materials in percentage by weight: polypropylene resin: 29.2-79.85%; polyethylene resin: 10-25%; elastomer: 0-10%; light diffuser: 0-5%; inorganic filler: 10-30%; nucleating agent: 0.05-0.5%; antioxidant: 0.1-0.3%; wherein the polypropylene resin is an impact copolymer polypropylene, and the ratio of the characteristic viscosity of the rubber phase to that of the polypropylene resin is 1-1.2; the polyethylene resin is prepared by using a metallocene catalyst. The present application optimizes the formula of the composition, significantly improves the transmittance, impact resistance and dimensional stability of the polypropylene material on the basis of maintaining excellent mechanical properties, so as to meet the market demand for high-performance polypropylene materials.

This invention discloses a method for producing composite spun fiber rolls, belonging to the field of new composite fiber materials. The method includes the following steps: raw material preparation, composite spinning, melt filtration, spinneret formation, cooling and forming, drawing and heat setting, and winding. This invention utilizes a core-sheath composite structure design, using a multi-component polyester with added nano-antistatic agents and compatibilizers as the sheath component and polyester PET chips as the core component. Optimizing the melting characteristics of the modified multi-component polyester sheath and the PET chips core, the invention optimizes the temperature parameters of each zone of the screw, the two-stage drawing and heat setting process, and the winding parameters. This solves the problems of poor antistatic effect, insufficient mechanical properties, high thermal shrinkage, poor spinning process stability, and poor roll formability of existing polyester composite fibers. The resulting composite fiber roll possesses excellent properties such as durable antistatic properties, high strength, and low shrinkage, and the process is highly controllable and efficient, making it suitable for large-scale industrial production.

The application discloses a BMC material with low styrene odor for plastic packaging motor and a preparation method and application thereof. The material comprises, by mass percentage, 10-16% of ortho phenyl type unsaturated polyester resin, 3-6% of styrene solution containing polystyrene PS and 0.5-3% of polyethylene PE powder as low shrinkage additives, 0.5-1.5% of release agent, 0.1-0.3% of curing agent, 0.01-0.1% of polymerization inhibitor, 0.1-1% of coupling agent, 0-2% of powder modifier, 0-70% of calcium carbonate powder, 0-70% of aluminum hydroxide powder and 5-10% of glass fiber. In the preparation, the powder modifier is first sprayed on the modified filler, then mixed with the resin liquid material, and finally the glass fiber is added and kneaded. The styrene content is reduced by combining the PE powder and the PS solution, the filler surface modification and the coupling agent are combined, low cost, low styrene release (≤200 ppm), low shrinkage rate (≤0.08%) and high strength are realized, and the application requirements of the plastic packaging motor shell or parts are met.

This invention proposes a low-shrinkage photocurable elastic resin composition based on synergistic compensation and its application. The resin composition has low viscosity and excellent photocurable printing properties. During molding, the non-reactive diluent is volatilized first by a simple stepwise heating of the printed model, and then the temperature is raised to the foaming temperature to cause the thermally expanding microspheres to expand and foam. At this temperature, the chain extender is further condensed. Through the synergistic effect of the non-reactive volatile diluent and the thermally expanding microspheres, physical compensation for curing shrinkage is achieved, which can meet the requirements of both low shrinkage and high elasticity. The method is simple and easy to implement and suitable for industrial applications.

The application discloses a kind of water conservancy pipeline stable backfill structure and construction method, it is related to buried pipe construction technical field, including from below to above sequentially arranged backfill base layer, backfill pipeline layer and top layer;The backfill pipeline layer includes embedded pipeline and the flow state solidified soil backfill material around it, and the backfill pipeline layer is divided into below backfill line portion and above backfill line portion with backfill line as boundary.This patent takes flow state solidified soil as core backfill material, realizes "self-compacting filling+low shrinkage" by component optimization and construction technology innovation.Structurally, below backfill line portion uses high flowability backfill material, to ensure that pipeline axillary angle and other machinery cannot reach area self-compacting filling;Above backfill line portion uses low flowability backfill material, to reduce flowability to prevent bleeding, reduce shrinkage crack.Construction uses secondary pouring method: first pouring below backfill line portion to backfill line, after curing initial setting, then secondary pouring above backfill line portion.

The utility model relates to spinning cooling device technical field and disclose high stability low shrinkage polyester industrial yarn production is with spinning cooling device, including support plate, the upper surface fixed connection of support plate has the sleeve, the front and back inner wall of sleeve inside all are established with circular groove, cooling assembly, cooling assembly sets up in two circular grooves, and cooling assembly includes two circular sealing plates, two circular sealing plates are respectively and rotate the clamping in the inner wall of two circular grooves, the opposite surface of two circular sealing plates all are fixedly connected with fixed sleeve, and the inner wall fixed sleeve of two fixed sleeves is connected with cooling pipe, and the outer wall fixed sleeve of cooling pipe is connected with spiral heat sink, and spiral heat sink is located at the opposite surface department of two fixed sleeves, through the stable output of servo motor, the meshing drive of pinion and spur gear makes cooling pipe and spiral heat sink keep even rotating speed, avoids the cooling unevenness caused because of rotating speed fluctuation, ensures that polyester industrial yarn has high stability and low shrinkage after cooling.

A Nickel based superalloy comprising 12.0 to 15.0 wt% Chromium, 1.0% to 2.0% Molybdenum, 3.0-12.0 wt% Tungsten, 1.2 to 2.0 wt% Aluminium, 1.2 to 2.0 wt% Titanium 1.2 to 2 wt% Niobium, 0.03 to 0.13 wt%

The application provides a ceramic blank with low shrinkage rate and a preparation method and application thereof, and the ceramic blank comprises solid-phase raw materials, liquid-phase raw materials and modified rare earth alumina microspheres, the mass ratio of the solid-phase raw materials to the liquid-phase raw materials is (2-5):(5-8), and the proportion of the added amount of the modified rare earth alumina microspheres to the total mass of the solid-phase raw materials and the liquid-phase raw materials is (0.1-10):(90-99.9); wherein the solid-phase raw materials comprise the following components in mass fraction: 20.0-60.0 parts of an aluminum source, 55.0-80.0 parts of a silicon source, 0.8-2.0 parts of Fe2O 3 3, 0.2-5.0 parts of a calcium source, and 0.1-1.0 parts of MgO. In the application, rare earth is introduced into the ceramic blank, and due to the high surface activity and good stability of the rare earth, the binding state between blank particles can be optimized, and the anti-shrinkage performance is improved.

This invention relates to a nano-metakaolin-modified hydraulic lime-based composite material and its preparation and application. The composite material comprises natural hydraulic lime and nano-metakaolin dispersed in the natural hydraulic lime, wherein the mass ratio of natural hydraulic lime to nano-metakaolin is (60-90):(10-40). The nano-metakaolin-modified hydraulic lime-based composite material of this invention exhibits controllable dispersibility and fluidity in the slurry after mixing with water. It also demonstrates good rock compatibility, low soluble salt content, controllable curing time, suitable post-curing strength, low permeability, and low shrinkage and expansion rate. The presence of a repair agent can specifically enhance the additional protective performance of the reinforcement material. It possesses high applicability, safety, and durability for the protection of stone cultural relics, without causing derivative damage.

This invention discloses a low-shrinkage protective film and its preparation method, relating to the field of film material technology. A low-shrinkage protective film comprises a surface functional layer, a PET substrate layer, a pressure-sensitive adhesive layer, and a release layer sequentially disposed therefrom. The PET substrate layer comprises the following raw materials in parts by weight: 65-80 parts polyethylene terephthalate; 18-25 parts polycarbonate; 4-8 parts compatibilizer; 3-6 parts styrene-sodium methacrylate ionomer; 1-2.5 parts rare earth oxides; 1-3 parts talc; and 2-5 parts nano-silica. The low-shrinkage protective film provided in this application, as an electronic screen protector, can effectively prevent shrinkage and edge curling.