1239 results about "Low density" patented technology

The invention belongs to the technical field of metal material engineering, and relates to a light high-toughness low-cost aluminum alloy and a preparation method thereof.The alloy comprises, by mass, 7.0%-9.2% of Mg, 2.5%-4.0% of Zn, 0.06%-0.20% of Zr, 0.01%-0.03% of Sb, main impurities including Fe smaller than or equal to 0.15%, Si smaller than or equal to 0.12%, other single impurities smaller than or equal to 0.05%, the total impurity smaller than or equal to 0.15% and the balance Al. Compared with 2xxx series and 7xxx series aluminum alloys, the alloy has certain advantages in the aspects of density, specific strength, ductility, corrosion resistance and the like, and has a remarkable cost advantage compared with a low-density aluminum-lithium alloy, so that the core competitiveness of an alloy product is improved, and the alloy product has the potential of becoming a next-generation commercial aluminum alloy.

The invention relates to the technical field of research and development of BIB liquid packaging materials, and discloses a PE-PA-based composite film, a manufacturing process and an application in BIB liquid packaging, and specifically comprises the following steps: synthesizing a PE-PA compatilizer; the preparation method comprises the following steps: carrying out ring-opening reaction on an epoxy functional group of a PE-PA compatilizer and an amino functional group or a carboxyl functional group at a PA resin molecular chain end to prepare PE-PA compatilizer grafted nylon resin, and carrying out physical anchoring action on a long-chain alkane structure on the PE-PA compatilizer grafted nylon resin and a PE resin molecular chain to prepare the PE-PA alloy master batch; low-density polyethylene resin is used as a raw material of a supporting layer, PE-PA alloy master batch is used as a raw material of a functional layer, metallocene polyethylene resin is used as a raw material of a heat sealing layer, a three-layer co-extrusion blow molding film forming technology is adopted, the PE-PA composite film is prepared, and the film product is excellent in comprehensive performance and can be used for manufacturing a BIB bag body.

An MIM preparation method for an ultrahigh heat-conducting composite material based on diamonds and red copper. The method comprises the preparation of a mixture, internal mixing granulation, injection molding, and degreasing sintering. By means of the MIM process, not only can uniform mixing and high-density molding of diamonds and a red copper powder be achieved, thereby effectively overcoming the technical problems of non-uniform dispersity, low density, etc. during the preparation of a high-heat-conductivity composite material by means of a traditional process, but the shape and size of a product can also be accurately controlled, particularly during the production of a sheet material having a thickness of less than 1 mm; moreover, the heat conductivity (the heat conductivity thereof being up to 500-800 W / (m·K)) thereof is significantly improved and is significantly higher than that of a traditional metal material. In addition, by optimizing MIM process parameters and selecting raw materials having higher cost effectiveness, the present invention effectively reduces the production cost, such that large-scale use of the high heat-conducting composite material based on diamonds and red copper becomes possible, thereby satisfying the high-standard requirements of high-performance electronic equipment for heat dissipation materials.

The invention discloses a high-toughness polyethylene composite film and a preparation method thereof, and belongs to the field of high polymer materials. The outer layer is prepared from linear low-density polyethylene, an ethylene-butyl acrylate copolymer, an antioxidant 1010 and an ultraviolet light absorber UV-531; the middle layer is prepared from linear low-density polyethylene, a polyolefin elastomer, an ethylene-butyl acrylate copolymer, stearic acid modified calcium carbonate, an antioxidant and an ultraviolet light absorber; and the inner layer is composed of linear low-density polyethylene, an ethylene-butyl acrylate copolymer, an antioxidant 1010 and an ultraviolet light absorber UV-531. Drying the raw materials; mixing heavy calcium carbonate with stearic acid; each layer is mixed at a low speed according to a ratio; and carrying out three-layer co-extrusion film blowing, two-way stretching, corona and annealing. The surface tension of the composite film reaches 40 mN / m, the maximum longitudinal and transverse tensile strength is 23 MPa, the tearing strength is 120 kN / m, the elongation at break is 700%, and the performance of the composite film is superior to that of traditional casting and blow molding process products.

The invention discloses a cable insulating material which comprises the following components in parts by weight: 40-60 parts of low-density polyethylene, 20-30 parts of an ethylene-vinyl acetate copolymer EVA, 2-5 parts of a composite anti-aging agent, 5-10 parts of a core-shell structure nano composite modifier, 1-2 parts of a lubricant, 3-8 parts of a compatilizer, 20-30 parts of a composite flame retardant, 5-10 parts of a nano reinforcing agent and 2-4 parts of phenylsilane. The core-shell structure modifier strengthens interface bonding, and cooperates with the modified nano reinforcing agent to disperse stress, so that the mechanics and high and low temperature resistance are improved; the composite anti-aging agent inhibits multi-path aging and improves the aging resistance. The material has the advantages of excellent mechanical properties, high and low temperature resistance and outstanding aging resistance, and meets the insulation quality and efficiency requirements of cables in complex use environments.

The invention discloses a tin-based alloy preformed soldering lug and a preparation method thereof.The preparation method comprises the following steps that a copper fiber reinforced framework with gradient density distribution is prepared, the copper fiber reinforced framework comprises a high-density area and a low-density area, and hollowed-out gaps are formed through a weaving technology; tin-based slurry with different components and functions is prepared from outer-layer slurry with tin-antimony-copper-nickel as a main body, middle-layer slurry with tin-antimony-copper as a base body and inner-layer slurry with tin-antimony-copper rare earth as a base body, the three kinds of tin-based slurry are sequentially filled into preset areas of hollow-out gaps of a reinforced framework, and a gradient structure material is formed; the gradient structure material is subjected to press-fit forming and post-treatment, and a preformed soldering lug is obtained; a framework is firstly built, then materials are filled, and copper fibers in the soldering lugs provide good support and heat conduction channels, so that a gradient transition structure with continuous change of components and performance is realized, and the integrity, the impact resistance and the bonding strength of the materials are greatly enhanced.

The invention provides a low-dielectric glass fiber composition as well as glass fibers, electronic cloth and a composite material thereof. The glass fiber composition comprises the following components in percentage by weight: 50.0 to 58.0 percent of SiO2, 10.0 to 16.9 percent of Al2O3, 19.0 to 27.3 percent of B2O3, 2.3 to 6.6 percent of CaO, 0.2 to 4.0 percent of MgO, 0.01 to 1.0 percent of SrO, 0.01 to 0.3 percent of Na2O, 0.01 to 0.45 percent of K2O, 0.01 to 0.5 percent of Fe2O3, 0.01 to 0.49 percent of TiO2, 0.01 to 1.7 percent of F2, 0 to 1.4 percent of ZrO2, 0.12 to 1.8 percent of F2 + K2O, 0.05 to 2.0 percent of F2 + SrO, 0.03 to 0.49 percent of Na2O + K2O, greater than or equal to 0.6 percent of K2O / Na2O, greater than or equal to 0.5 percent of F2 / K2O, 3.0 to 9.8 percent of CaO + MgO + SrO and 72.0 to 84.0 the range of C2 = (F2 + K2O) / Na2O is greater than or equal to 1.4, the range of C3 = (F2 + K2O) / (Na2O + TiO2) is greater than or equal to 0.5, the range of C4 = (MgO + SrO) / CaO is greater than or equal to 0.05, and the range of C5 = (SiO2 + B2O3) / (CaO + MgO + Al2O3 + TiO2) is greater than or equal to 3.0; and the glass fiber composition does not contain lithium oxide. The glass fiber composition has the characteristics of low dielectric, low loss and low density, can improve the glass modulus, reduce the glass forming temperature, devitrification temperature and rate, can also reduce the surface tension and clarification difficulty of molten glass, has more cost advantages, and is suitable for large-scale production of low-dielectric glass fibers.

A lid assembly for an in-ground meter box that can withstand substantial loads (e.g., 22, 500 lbs) without deformation. The lid assembly includes a metal frame secured to the bottom side of a plastic lid to allow the plastic lid to seat tightly for covering the in-ground meter box. The metal frame provides the rigidity and strength to withstand the loading while simultaneously providing the lid with sufficient weight to make it non-bouyant, i.e., should the surrounding ground environment become flooded, the lid is heavy enough to remain in place, covering the meter box and will not float away. The metal frame also is detectable by a metal detector should the lid every be covered over with debris and need to be located. The plastic lid body (e.g., linear low-density polyethylene (LLDPE)) of the lid assembly avoids radio signal interference or attenuation emanating from a transmitter positioned within the meter box.

The invention discloses an Al-Mg-Zn aluminum alloy plate with excellent strong plasticity and light weight characteristics as well as a preparation method and application of the Al-Mg-Zn aluminum alloy plate. The alloy comprises the following components in percentage by mass: 5.0%-5.5% of Mg, 1.5%-2.0% of Zn, 0.4%-0.5% of Mn, 0.1%-0.3% of Cu, 0.15%-0.25% of Sc, 0.1%-0.15% of Zr, 0.05%-0.15% of Ag, less than or equal to 0.1% of impurities and the balance of Al. The density is not more than 2.63 g / cm < 3 >, the tensile strength is not less than 470 MPa, and the ductility is not less than 23%. The preparation method comprises the steps of high-purity raw material smelting and casting, two-stage homogenization, hot rolling, intermediate annealing, cold rolling, solid solution treatment and single-stage aging. Wherein the total pressing amount of hot rolling is 80-85%, the total pressing amount of cold rolling is 20-35%, and the single-stage aging time is 120-140 DEG C * 16-24 h. The microstructure of the alloy is characterized in that the average size of dispersed AlSc particles is smaller than or equal to 100 nm, the area fraction of deformed grains is larger than or equal to 70%, the average size of nanometer beta-AlMg and T-Mg (Al, Zn) composite precipitated phases is smaller than or equal to 20 nm, the number density is larger than or equal to 1 * 10 < m >, the area fraction of micron-order second phases is smaller than or equal to 0.5%, and the alloy is only formed by impurity Fe. According to the method, the traditional two-stage aging process is simplified, low density, high strength and high plasticity are synchronously improved, and the method is suitable for large-scale industrial application.

The invention discloses a high-barrier polyethylene film and a preparation method thereof, and relates to the technical field of high polymer materials. The invention discloses a high-barrier polyethylene film. The high-density polyethylene composite material is prepared from the following raw materials in parts by weight: 25 to 40 parts of high-density polyethylene, 15 to 30 parts of linear low-density polyethylene, 8 to 16 parts of ethylene-vinyl alcohol copolymer, 3 to 8 parts of nano montmorillonite, 5 to 10 parts of modified layered double hydroxide, 2 to 6 parts of nano silicon dioxide aerogel, 0.2 to 0.6 part of antioxidant 1076, 0.1 to 0.4 part of light stabilizer UV-770, 3 to 7 parts of tributyl citrate and 1 to 3 parts of octadecanamide. 1-3 parts of polyethylene wax, 0.6-1.2 parts of a silane coupling agent KH560 and 7-12 parts of a functional additive. According to the high-barrier polyethylene film disclosed by the invention, by using the modified layered double hydroxide and the functional additive, the barrier property and the antibacterial property are enhanced, the mechanical property is improved, the comprehensive performance is excellent, and the application prospect is good.

The invention relates to the technical field of composite films, and provides a PE film, a preparation method thereof and application of the PE film in metal powder packaging. The PE film comprises an outer layer, a middle layer and an inner layer which are sequentially arranged, preparation raw materials of the outer layer comprise low-density polyethylene, linear low-density polyethylene, metallocene medium-density polyethylene and a processing aid, and preparation raw materials of the middle layer comprise low-density polyethylene, linear low-density polyethylene, high-density polyethylene and a processing aid. And the inner layer is prepared from the following raw materials: low-density polyethylene, an antistatic agent and a processing aid. When the PE film is used for packaging metal powder, the effect that the metal powder does not adhere to a bag can be achieved, the phenomenon that a seal is not firm due to the fact that metal adheres to the seal is avoided, meanwhile, waste of the metal powder is avoided, and the PE film has wide application prospects.

The invention relates to the technical field of cable materials, and particularly discloses a flame-retardant polyethylene sheath material for an ultrahigh-voltage cable and a preparation method thereof.The flame-retardant polyethylene sheath material for the ultrahigh-voltage cable provided by the invention takes low-density polyethylene as a main base material, and the molecular structure of the low-density polyethylene has more long-chain branches; and meanwhile, by adding the composite filler and the auxiliary agent, the prepared polyethylene sheath material has excellent mechanical properties, high and low temperature resistance and flame retardance.

The invention relates to the technical field of cables, and provides a high-temperature-resistant flame-retardant cable and a preparation method thereof. The high-temperature-resistant flame-retardant cable comprises a conductor and a flame-retardant outer sheath, the flame-retardant outer sheath is prepared from the following raw materials in parts by weight: 40 to 50 parts of linear low-density polyethylene, 35 to 45 parts of ethylene-vinyl acetate copolymer, 10 to 15 parts of ethylene propylene diene monomer, 15 to 18 parts of modified aluminum hydroxide, 10 to 14 parts of modified magnesium hydroxide, 5 to 8 parts of polyethylene grafted maleic anhydride, 5 to 8 parts of microencapsulated red phosphorus, 2 to 3 parts of silane coupling agent and 0.8 to 1 part of antioxidant. The composite material is prepared from the following components in parts by weight: 0.5-1 part of a light stabilizer, 0.5-1 part of calcium stearate, 0.8-1 part of polyethylene wax and 0.5-0.9 part of carbon nanotubes. According to the cable prepared in the invention, the performance stability of an existing high-temperature-resistant material in a high-temperature environment is improved, and the problems of softening, melting and the like of the cable are avoided.

The invention discloses a preparation method of a high-temperature-resistant wave-absorbing honeycomb sandwich structure in the technical field of wave-absorbing materials, which comprises the following steps: synthesizing a transition metal modified polycarbosilane precursor under the protection of inert gas, and performing high-temperature cracking to obtain a magnetic silicon carbide wave-absorbing agent; blending and grinding the wave-absorbing agent and high-temperature-resistant resin to prepare a wave-absorbing glue solution; after a honeycomb core material is formed by adopting inorganic fiber cloth, a wave-absorbing glue solution is loaded through a repeated dipping-drying process, and the high-temperature-resistant wave-absorbing honeycomb is obtained through gradient heat treatment. And finally, compounding and curing with the wave-transparent skin and the carbon fiber composite material through a high-temperature-resistant adhesive film. The sandwich structure is prepared on the basis of the composite material, and the magnetic silicon carbide wave-absorbing agent has the characteristics of high temperature resistance, low density, oxidation resistance and adjustable dielectric property; the phthalocyanine resin matrix is adopted, so that excellent formability and high-temperature stability are guaranteed; honeycomb nodes are sewn and reinforced by silicon carbide fibers, so that the problem of node cracking in a high-temperature environment is solved.

The invention discloses equipment and a method for preparing an aluminum silicon carbide (Al-SiC) composite material through a pressure infiltration process, and belongs to the technical field of metal matrix composite material preparation. The efficient pressure preparation equipment for the aluminum-silicon carbide composite material comprises a furnace body, a lower graphite crucible, an upper graphite crucible, a liftable graphite rod, an inflation connector and an exhaust connector, during specific use, an aluminum ingot and a silicon carbide preform are heated respectively and prevented from making contact with each other, so that the interface reaction strength is relieved, and combination of aluminum and silicon carbide is facilitated; after the target temperature is reached, the graphite rod is lifted to open the leak hole, so that the molten aluminum falls into the lower graphite crucible, and under the action of high-pressure gas, the molten aluminum is infiltrated into the silicon carbide prefabricated body, so that the aluminum-silicon carbide composite material is prepared; the problems of low density, poor process stability, violent interface reaction and low bonding strength in the prior art can be solved.

The invention provides a phase change enhanced ablation-resistant modified liquid silicone rubber material as well as a preparation method and application thereof, and belongs to the field of advanced materials. According to the invention, paraffin is adopted as a phase change filler, so that the ablation resistance and heat insulation performance of the expanded ceramic liquid silicone rubber material are remarkably improved, and the prepared silicone rubber composite material has the advantages of low density, low ablation surface temperature, strong carbon layer and high heat absorption capacity. The phase-change reinforced modified expanded ceramic flexible ablation-resistant material further improves the ablation resistance and high-temperature heat insulation performance of a liquid silicone rubber material, and has a good application prospect in the fields of aerospace thermal protection, building heat insulation and the like.

The invention provides a high-strength fiber composite material based on aramid 1414 fibers and a preparation method of the high-strength fiber composite material, and belongs to the technical field of composite materials. The composite material comprises 60%-80% of aramid 1414 fibers and 20%-40% of a resin matrix, the aramid 1414 fibers are subjected to surface treatment and size stabilization treatment through a specific process, and the compatibility of the fibers and the resin matrix and the overall performance of the composite material are fully improved. According to the invention, the characteristics of high strength and high modulus of the aramid 1414 fiber are utilized, so that excellent mechanical properties are provided; due to the low-density characteristic of the aramid 1414 fibers, the composite material is light while high strength is kept, and the performance requirements of light weight and high strength are met. The composite material disclosed by the invention not only has excellent mechanical properties, but also realizes the balance of cost effectiveness and production efficiency by optimizing a preparation process, and has a wide market application prospect.

The invention provides a low-density high-strength aluminum-based composite material and a preparation method, and relates to the technical field of aluminum alloy powder metallurgy preparation. The composite material is composed of two parts: a matrix alloy and hollow glass beads, wherein the addition amount of the hollow glass beads is 5-30 wt.%. The matrix alloy comprises the following components in percentage by mass: 0 to 6.0 percent of Cu, 0 to 3.0 percent of Mg, 0 to 8.4 percent of Zn and the balance of Al and inevitable impurities; the hollow glass beads are prepared from the following components in percentage by mass: 70 to 80 percent of SiO2, 8 to 15 percent of CaO, 5 to 15 percent of Na2O, 3 to 8 percent of B2O3 and 2 to 3 percent of Al2O3. The composite material is prepared through surface modification of hollow glass beads, preparation of composite powder, preparation of a composite material green body, sintering densification, deformation processing and heat treatment. According to the technology, low-cost preparation and processing of the low-density and high-strength aluminum-based composite material can be achieved, the technological process is simple, the production efficiency is high, the method is suitable for large-scale industrial production, and the application prospects in the fields of aerospace, new energy automobiles, ships, electronic communication and the like are huge.

The invention discloses a polyimide composite material and a preparation method thereof, and relates to the technical field of functional composites.The polyimide composite material is composed of hollow quartz fibers and silicon-containing polyimide resin, the fiber volume content of the polyimide composite material is 45%-60%, and the density of the polyimide composite material is 1.25-1.55 g / cm < 2 >; wherein the silicon-containing polyimide resin is formed by polymerizing a mixture of aromatic dianhydride, aromatic diamine and diamine containing a siloxane structure, and an end-capping reagent. The preparation method comprises the following steps: synthesizing a polyamide acid solution, preparing a prepreg by preimpregnation, performing by a vacuum bag method, performing hot-pressing curing and performing high-temperature post-treatment. Through collaborative innovation of the components and the process, the preparation method is simple, and the composite material has ultralow density, ultrahigh heat resistance, low dielectric constant and high strength and is suitable for the fields of aerospace, 5G communication, semiconductors and the like.

The invention relates to the technical field of optimization design and fatigue life analysis, and discloses an open combined deck weld joint arrangement and fatigue life collaborative topological optimization method, which comprises the following steps of: establishing a finite element model of an open deck and performing statics analysis; material distribution is optimized by adopting a topological optimization technology, high and low density areas are distinguished, and welding seams are reasonably arranged at junctions; the optimization result is verified and iteratively adjusted; and carrying out fatigue analysis based on the optimization model, and carrying out secondary topological optimization by taking the fatigue life as a constraint condition. According to the technical scheme, the lightweight design of the open deck is achieved, meanwhile, the structural rigidity and strength are improved, the fatigue life is prolonged, material energy consumption is effectively reduced, and the method is suitable for optimal design of complex structures such as ships and ocean platforms and has wide application prospects.

The invention discloses a preparation method of a high-density carbon-carbon composite material, which comprises the following steps: soaking a needled prefabricated body in a resin mixed solution, vacuumizing and dipping, drying in a drying oven, then putting into a mold, carrying out hot-pressing curing molding, and carbonizing to obtain the high-density carbon-carbon composite material. According to the preparation method, the carbon-carbon composite material with the density larger than 1.2 g / cm < 3 > can be obtained through one-time dipping and one-time hot pressing, the production period is short, energy consumption is low, the production cost is remarkably reduced, and the carbon-ceramic composite material with the density larger than 1.2 g / cm < 3 > can be obtained through one-time dipping and one-time hot pressing. And the prepared carbon-carbon composite material can achieve a high-density effect when the density is low, and has the characteristics of good air tightness, difficulty in deformation at high temperature and the like.

A house wrap for a building comprises a reinforcing drainage plane layer configured to face the outside of the building; a breathable, non-perforated barrier film bonded to the drainage plane layer; and at least one insulating layer including a perforated expanded low density polyethylene foam layer, wherein in the expanded low density polyethylene layer at least 80% of the blowing agents are dissipated from closed cells within the expanded low density polyethylene layer, forming evacuated closed cells whereby a partial vacuum is formed within the closed cells of the low density polyethylene layer.

A lap-sealable film comprises a non-oriented film, a heat-resistant lacquer (HRL), and a sealing layer. The non-oriented film comprises a first outer layer and a second outer layer. The first outer layer comprises a first polymeric blend having a low density polyethylene (LDPE) and an ethylene copolymer. The second outer layer comprises a non-oriented high density polyethylene (HDPE). The HRL is attached to the first outer layer and is coextensive with less than 100%, by area, of the exterior surface of the first outer layer. The sealing layer comprises an ethylene copolymer or a second polymeric blend having a LDPE and an ethylene copolymer. The ethylene copolymer has a density less than or equal to 0.92 g / cm3. The first polymeric blend has a seal initiation temperature less than or equal to 110°C. The lap-sealable film comprises a total composition having greater than or equal to 80% polyethylene.

The invention provides an aluminum oxide aerogel composite material as well as a preparation method and application thereof, and belongs to the technical field of aluminum oxide aerogel preparation. The preparation method provided by the invention comprises the following steps: (1) preparing aluminum sol by taking coal gangue as an aluminum source; (2) mixing the aluminum sol obtained in the step (1) with aluminum silicate fibers, and performing gelation to obtain composite hydrogel; and (3) mixing the composite hydrogel obtained in the step (2) with ethanol, aging, mixing with a modifier, modifying, and carrying out graded normal-pressure drying to obtain the aluminum oxide aerogel composite material, the modifier in the step (3) is one or more of absolute ethyl alcohol, tetraethoxysilane and normal hexane. The alumina aerogel composite material prepared by the preparation method provided by the invention has the characteristics of low density, low heat conductivity coefficient and high strength, and is suitable for the high-temperature processing field of special materials and the aerospace field.

The invention discloses a ceramic component gradient modified C / C-SiC-ZrC composite material and a preparation method thereof, and belongs to the technical field of carbon / carbon composite material matrix modification preparation, a carbon fiber preform and a heating element are placed in chemical liquid phase vaporization deposition equipment, a precursor solution is added until the carbon fiber preform is fully soaked, and a ceramic component gradient modified C / C-SiC-ZrC composite material is obtained; and carrying out chemical liquid phase vaporization deposition reaction to obtain the low-density C / C composite material with porosity in unidirectional gradient distribution. And putting the mixture into a graphite crucible with a carbon-rich area facing downwards and a carbon-less area facing upwards, completely putting the graphite crucible into the ceramic powder for modification, reacting and infiltrating, and cooling to room temperature to obtain the C / C-SiC-ZrC composite material with the gradient modified ceramic components. The end with high ceramic content endows the material with a high-temperature thermal protection function, the end with high pyrolytic carbon content can effectively conduct heat generated in a ceramic-rich area, and the end with low ceramic content can effectively conduct heat generated in a ceramic-rich area. Due to the gradient design from the ceramic-rich area to the carbon-rich area, the material has high-temperature oxidation resistance and ablation resistance and is light, and lightweight design of an aerospace thermal protection structure is facilitated.

The invention discloses a tri-state fluid as well as a preparation method and application thereof. The three-state fluid comprises a water phase, a macromolecular thickening agent, a surfactant and hydrophobic aerogel particles, the macromolecular thickening agent, the surfactant and the hydrophobic aerogel particles are uniformly dispersed in the water phase, and the hydrophobic aerogel particles form a continuous three-dimensional network in the water phase. The three-state fluid has the structural characteristic of solid-liquid-gas three-phase state continuous interpenetration. The three-state fluid disclosed by the invention has the characteristics of low density and ultra-light weight of aerogel, fluidity of a fluid material and the like, solves the problem of uniform dispersion of an ultra-light aerogel material in a high-density fluid, and controls aerogel particles to form a dynamic stable continuous solid-gas network in the fluid; the material shows excellent performance in the aspects of shock absorption, damping, high-performance thermal insulation material forming and the like, and a new thought is provided for preparing a novel fluid material.

The invention relates to the technical field of packaging materials, in particular to a PE composite film for manufacturing a packaging bag and a preparation method of the PE composite film. The PE composite film comprises a lower antibacterial PE layer, a middle barrier PE layer and an upper antibacterial PE layer; the lower antibacterial PE layer is prepared from the following raw materials: low-density polyethylene, linear density polyethylene, an antibacterial functional agent, a tensile functional agent and an auxiliary agent; the middle barrier PE layer is prepared from the following raw materials: linear low-density polyethylene, metallocene low-density polyethylene, a tensile functional agent and an auxiliary agent; the upper antibacterial PE layer is prepared from the following raw materials: linear low-density polyethylene, metallocene low-density polyethylene, an antibacterial functional agent and an auxiliary agent, and the PE composite film for manufacturing the packaging bag, prepared by the invention, has excellent antibacterial property and excellent tensile mechanical property; the requirements on antibacterial property and tensile property in the field of packaging materials can be met.

The invention relates to the technical field of polyethylene packaging films, and particularly discloses an antibacterial polyethylene composite packaging film and a preparation method thereof.The antibacterial polyethylene composite packaging film comprises an inner layer, a middle layer and an outer layer, the inner layer is prepared from the following raw materials in parts by weight: 60 to 80 parts of low-density polyethylene, 25 to 35 parts of polypropylene, 4 to 6 parts of modified filler, 0.3 to 0.6 part of antioxidant and 1 to 3 parts of compatilizer; the middle layer is prepared from 62 to 75 parts of high-density polyethylene, 28 to 40 parts of ethylene-vinyl alcohol copolymer, 0.8 to 1 part of anti-binding agent and 2 to 5 parts of compatilizer; the outer layer comprises 55-70 parts of high-density polyethylene, 35-45 parts of metallocene polyethylene, 12-25 parts of nylon, 4-10 parts of antibacterial modified montmorillonite and 3-6 parts of compatilizer, the polyethylene composite packaging film has good processability and good stability, the composite film adopts a double-layer antibacterial design of the inner layer and the outer layer, the middle layer has excellent barrier property and good compactness, and the polyethylene composite packaging film is suitable for being used as a packaging film. The composite packaging film has excellent antibacterial performance and mechanical performance and good comprehensive performance.

The invention discloses a high-strength rat-proof optical cable and a preparation method thereof. The high-strength rat-proof optical cable comprises at least one reinforcing piece, at least one cable core distributed outside the reinforcing piece, an inner protective layer wrapping the cable core, an armor layer wrapping the inner protective layer and a rat-proof outer sheath wrapping the armor layer, and the cable core is composed of at least one optical fiber and a loose tube; wherein the rat-proof outer sheath is prepared from the following raw materials in parts by weight: 70 to 80 parts of linear low-density polyethylene, 20 to 30 parts of nylon 12, 5 to 8 parts of compatilizer, 15 to 20 parts of modified composite filler, 1 to 3 parts of antioxidant and 0.5 to 1 part of lubricant. According to the high-strength rat-proof optical cable, the LLDPE / nylon 12 alloy matrix with a specific formula is adopted in the outer sheath, and the modified composite filler is introduced, so that the finally prepared optical cable outer sheath has excellent mechanical strength and wear resistance, and an efficient, long-acting and environment-friendly biological rat-proof effect is achieved.

The utility model discloses a midsole secondary foaming forming machine cooling device which comprises a base, the top of the base is fixedly connected with a fixing block, one side of the fixing block is provided with a round through groove, a placing assembly used for placing a mold is arranged in the round through groove, the top of the base is fixedly connected with a bearing seat, and the bearing seat is provided with a bearing block. A cylinder is rotationally connected into the bearing seat through a bearing, a cavity is formed in the cylinder, a spiral pipe is fixedly connected into the cavity, and a connecting frame is fixedly connected to the inner wall of the cylinder. According to the utility model, the surface of the mold can be uniformly cooled through rotating centrifugal force, the problems of local supercooling and insufficient cooling of the mold are reduced, the deviation of medium and low density is reduced, the rotating speed required by different foaming materials can be matched, the rotating speed adjusting time is shortened, and the convenience of the device is improved; and the placing frame can be pushed to the middle of the cylinder, so that the production efficiency of the device is improved.