20 results about "Medium-density polyethylene" patented technology

This application relates to the field of insulating materials, specifically disclosing a flexural insulating material, its preparation method, and a robot cable, comprising the following raw materials in parts by weight: 50-80 parts of low-density polyethylene, 30-40 parts of medium-density polyethylene, 30-40 parts of ethylene-tetrafluoroethylene-perfluoropropyl vinyl ether terpolymer, 1-20 parts of filler, 3-8 parts of compatibilizer, 0.1-5 parts of crosslinking agent, and 0.1-5 parts of co-crosslinking agent. This invention addresses the performance shortcomings of existing insulating materials, achieving a balance of flexural resistance, abrasion resistance, insulation stability, and excellent flexibility, thus meeting the stringent requirements of high-frequency cables used in robots / manipulators.

This invention relates to the field of insulation materials technology, specifically to a high-strength, tear-resistant, halogen-free, flame-retardant insulating material and its preparation method. The high-strength, tear-resistant, halogen-free, flame-retardant insulating material comprises the following components by weight: 70-90 parts EPDM rubber, 5-15 parts thermoplastic elastomer, 15-25 parts medium-density polyethylene, 10-20 parts ethylene-vinyl acetate copolymer, 3-5 parts triallyl isocyanate, 2-4 parts sulfur, 1-3 parts polyethylene wax, 3-5 parts zinc oxide, 1-3 parts antioxidant, 30-50 parts aluminum hydroxide, 20-40 parts modified silica, 0.2-0.5 parts ultraviolet absorber, 1-3 parts accelerator, and 2-4 parts silicone masterbatch. The high-strength, tear-resistant, halogen-free, flame-retardant insulating material prepared by this invention exhibits excellent tensile and tear resistance and flame-retardant properties, thereby extending its service life.

This invention relates to the field of plastic multilayer film molding technology, and discloses a co-extrusion molding method for coated multilayer polyethylene film, comprising: melting and extruding high-density polyethylene resin and medium-density polyethylene resin and molding them into a multilayer polyethylene co-extruded melt film; attaching it to the surface of a cooling roller and controlling the cooling to form a multilayer polyethylene base film; activating its surface by bombarding with a corona bombardment device to form an activated surface layer; coating the activated surface layer with an amide-based slip emulsion to form a wet coating and drying it. This invention reconstructs the cooling crystallization kinetics of the co-extruded melt, inhibits the crystallization of high-density polyethylene, forms a metastable amorphous skin layer with high free volume in situ on the outer surface, provides a sensitive target area for introducing polar groups, inhibits the crystal phase shear deformation of the film under high temperature conditions, blocks stress concentration, and ensures that the film maintains morphological stability in a high-temperature cooking environment.

This invention provides a bimodal medium-density polyethylene (MDPE) composition and a micro-irrigation drip tape comprising the MDPE composition. The MDPE composition can be extruded at high linear velocity while maintaining other desired properties. The MDPE composition comprises a high molecular weight (HMW) polyethylene component and a low molecular weight (LMW) polyethylene component. The MDPE composition has a molecular weight of 0.937 g / cm³. 3 Up to 0.946 g / cm 3 Density; high-load melt index (I21) of 7 g / 10 min to 20 g / 10 min; cross G' = G” of 30 kPa to 50 kPa; notched constant tensile load failure time greater than 700 hours at 30% yield stress as measured according to ASTM D5397; and strain hardening modulus greater than 65 MPa.

This application discloses a high puncture-resistant polyethylene geomembrane and its production apparatus and process, belonging to the field of geomembrane technology. The high puncture-resistant polyethylene geomembrane comprises, from top to bottom, an upper membrane, a first middle membrane, an inner membrane, a second middle membrane, and a lower membrane. By weight, the upper and lower membranes each comprise 90-100 parts of modified linear low-density polyethylene resin and 2-10 parts of dual-resistant black masterbatch; the first and second middle membranes each comprise 40-60 parts of medium-density polyethylene resin, 35-55 parts of metallocene high-density polyethylene resin, and 2-10 parts of dual-resistant black masterbatch; the inner membrane comprises 60-80 parts of medium-density polyethylene resin, 15-35 parts of linear low-density polyethylene resin, and 2-10 parts of dual-resistant black masterbatch. This application describes a polyethylene geomembrane with a symmetrical five-layer structure centered on the inner membrane. It specifically defines the components of each layer and the proportional relationship between the components, thereby simultaneously improving the puncture resistance and environmental stress cracking resistance of the polyethylene geomembrane to meet the needs of seepage prevention projects in harsh environments.

The gas barrier film is provided with a multilayer polyethylene film and a gas barrier layer, the multilayer polyethylene film has a surface layer, an intermediate layer, and an inner layer in this order, the surface layer is provided between the intermediate layer and the gas barrier layer, and the surface layer is composed of a medium-density polyethylene resin or a high-density polyethylene resin having a density of 0.926 g / cm3 or more. The composite elastic modulus of the surface layer and the inner layer is 1.45 GPa or more and less than 1.90 GPa, the composite elastic modulus of the intermediate layer is 1.80 GPa or more and less than 2.50 GPa, the ratio of the thickness of the intermediate layer to the total thickness of the surface layer and the inner layer is 0.5 or more, the temperature indicated by the maximum value of the melting peak of the multilayer polyethylene film exceeds 129 DEG C and less than 136 DEG C, and the thickness of the intermediate layer is 0.5 or more. The gas barrier layer has at least one of an inorganic oxide layer and a gas barrier coating layer.

Metallocene-catalyzed multimodal medium-density polyethylene (mMDPE), the use of said multimodal medium-density polyethylene (mMDPE) in membrane applications, and membranes comprising the mMDPE of the present invention.

The application provides a food packaging recycled film regenerated geomembrane and a preparation method thereof. The food packaging recycled film regenerated geomembrane comprises an outermost layer, an intermediate layer and an innermost layer arranged in sequence. The outermost layer and the innermost layer are symmetrically distributed with the intermediate layer as an axis. The outermost layer and the innermost layer comprise, by weight percentage, 85.0-95.0% of high-density polyethylene, 1.0-10.0% of medium-density polyethylene, 1.0-5.0% of a first compatilizer and 0.5-2.0% of silane modified montmorillonite. The intermediate layer comprises 75.0-93.0% of food packaging recycled film, 5.0-20.0% of a second compatilizer and 2.0-8.0% of ethylene-vinyl acetate copolymer. On the basis of the silane modified montmorillonite, the PA and PET in the food packaging recycled film can improve the mechanical properties such as stiffness and strength of the geomembrane. Thus, the geomembrane has good performance in all aspects and can be used as a replacement product of the virgin geomembrane.

A gas barrier film includes a multilayer polyethylene film and a gas barrier layer, in which the multilayer polyethylene film includes at least three layers of a front layer, an intermediate layer, and a rear layer in this order on the gas barrier layer side; the intermediate layer has a probe descent temperature which is higher than that of the front layer and is higher than or equal to that of the rear layer; the front layer is constituted of a medium-density polyethylene resin having a density of 0.926 g / cm3 or more, or a high-density polyethylene resin; and the gas barrier layer includes at least either of an inorganic oxide layer and a gas barrier coating layer.

This gas barrier film is provided with a multilayer polyethylene film and a gas barrier layer, the multilayer polyethylene film having at least a surface layer, an intermediate layer, and a rear surface layer in this order on the gas barrier layer side, and the probe drop temperature of the intermediate layer is higher than the probe drop temperature of the surface layer and is equal to or higher than the probe drop temperature of the rear surface layer. The surface layer is composed of a medium-density polyethylene resin or a high-density polyethylene resin having a density of 0.926 g / cm3 or more, and the gas barrier layer has at least one of an inorganic oxide layer and a gas barrier coating layer.

The invention relates to the technical field of photovoltaic cables, in particular to a multi-layer composite photovoltaic cable and a preparation method thereof. The photovoltaic cable comprises photovoltaic conductors which are sequentially arranged from inside to outside. The first fireproof layer wraps the outer side of the photovoltaic conductor and is formed by overlapping and wrapping a double-sided synthetic mica tape; the insulating layer coats the outer side of the first fireproof layer; the second fireproof layer coats the outer side of the insulating layer; the waterproof lining layer wraps the outer side of the second fireproof layer and is made of medium-density polyethylene; the liner layer wraps the outer side of the water-blocking lining layer and comprises a layered structure formed by wrapping a flame-retardant glass fiber tape; and the sheath layer coats the outer side of the liner layer. The photovoltaic cable provided by the invention has the advantages of fire prevention, water resistance, rat and ant prevention, long time efficiency, high environmental protection performance and the like, can stably operate in a fire or humid environment, and is beneficial to popularization and application of field laying.

This invention provides a halogen-free flame-retardant waterproof layer, a halogen-free flame-retardant waterproof membrane, and a method for preparing the same, belonging to the field of waterproof membranes and flame-retardant materials. The halogen-free flame-retardant waterproof layer comprises, by weight, 10-30 parts high-density polyethylene resin, 20-60 parts medium-density polyethylene resin, 0-10 parts linear low-density polyethylene resin, 5-20 parts ethylene-vinyl acetate copolymer resin, 5-10 parts ethylene-acrylic acid copolymer compatibilizer, 5-50 parts condensed-phase halogen-free flame retardant, 0.1-3 parts polyether block amide elastomer antistatic agent, 0.1-3 parts rare earth coupling agent, 0.1-1.5 parts dispersant, 0.1-1.5 parts antioxidant, and 0.1-1.5 parts light stabilizer; wherein the condensed-phase halogen-free flame retardant is selected from at least one of phosphorus-based flame retardants, phosphorus-nitrogen intumescent flame retardants, and silicon-based flame retardants. The waterproof membrane has a multi-layered structure, including a strong flame-retardant waterproof layer and a non-flame-retardant or weak flame-retardant waterproof layer, with the strong flame-retardant waterproof layer and the non-flame-retardant and / or weak flame-retardant waterproof layer being distributed alternately.

The invention relates to a nylon and medium density polyethylene composite flame-retardant inner sheath for a photovoltaic cable, which relates to the technical field of cable sheaths and comprises an inner layer, a first connecting layer, a middle layer, a second connecting layer and an outer layer. The composite material has the effects of high flame retardance and high mechanical property. The outer side of the inner layer is connected with the middle layer through the first connecting layer, the inner layer can provide high strength and wear resistance, provide structural support for the inner sheath, mechanically protect the cable and resist friction and bending stress during installation, and the middle layer can achieve the protection effect, resist external extrusion and serve as a flame-retardant carrier. And the mechanical strength and the flame-retardant effect of the inner sheath can be effectively improved, so that the protection effect on a cable line is improved, and the use requirements are met.

The application discloses a heat-shrinkable tube and a preparation method and application thereof. The heat-shrinkable tube comprises the following components in parts by weight: 40-60 parts of high-density polyethylene, 20-40 parts of medium-density polyethylene, 10-20 parts of elastomer and 0.1-0.5 parts of antioxidant. The heat-shrinkable tube provided by the application is excellent in rigidity and shrinkability and is non-toxic and harmless.

The invention discloses a multi-layer co-extrusion polyethylene composite film and a preparation method thereof. The composite film comprises a protective layer, a barrier layer and an antibacterial layer which are sequentially laminated and compounded, wherein the antibacterial layer is prepared from the following raw materials in parts by mass: 90 to 100 parts of linear low density polyethylene and 0.2 to 10 parts of modified zinc oxide; the barrier layer is prepared from the following components in parts by mass: 85 to 95 parts of medium density polyethylene, 0.5 to 5 parts of modified aluminum oxide and 5 to 10 parts of compatilizer; the protective layer is prepared from the following raw materials in parts by mass: 90 to 100 parts of high-density polyethylene, 0.1 to 0.5 part of heat stabilizer and 0.1 to 1 part of cross-linking agent. According to the invention, polyethylene is taken as a single matrix, a three-layer co-extrusion cast film technology is utilized, and sectional gradual cooling and low-energy electron beam radiation crosslinking modification are matched, so that the composite film with a three-layer structure of a protection layer, a barrier layer and an antibacterial layer is prepared, and the composite film has excellent barrier property, antibacterial property and mechanical property.

The present disclosure relates to a metallocene-catalysed multimodal medium density polyethylene (mMDPE), inclusion of the multimodal medium density polyethylene (mMDPE) in film applications, and film including the mMDPE of the disclosure.

The invention discloses a high-low temperature PE film for medical instrument packaging and a processing method thereof.The PE film is of a three-layer or five-layer co-extrusion structure, a bag can be directly made without compounding, and the PE film comprises a heat sealing layer, a middle layer and an outer layer which are sequentially arranged from inside to outside; the heat sealing layer is a low-temperature heat sealing layer and consists of a mixture of POE (Polyolefin Elastomer) metallocene, KN resin and metallocene polyethylene; the number of the middle layers is 1-3, and the middle layers are composed of a mixture of a high-density metallocene material, HDPE and medium-density polyethylene. And the outer layer consists of a mixture of high-density metallocene polyethylene, LDPE (Low-Density Polyethylene) and an anti-blocking agent. Through the co-extrusion structure, direct bag making without compounding is achieved, the process is simplified, cost is reduced, and the problems of traditional complex compounding and layering are solved; the specific raw material ratio of each layer realizes low-temperature heat sealing, high strength and good opening property, and avoids instrument damage, film damage and adhesion.

This invention belongs to the field of resin materials technology. This invention provides a pipe lining resin and its preparation method, which includes the following steps: S1, vacuum drying nylon 6 to obtain dried nylon; S2, mixing 19.5-20.5 parts by weight of the dried nylon, 4.9-5.2 parts by weight of compatibilizer, 68-72 parts by weight of medium-density polyethylene, 1.4-1.6 parts by weight of modified graphite nanosheets, and 3.4-3.6 parts by weight of maleic anhydride-grafted ethylene-octene copolymer to obtain a mixture; S3, melt-extruding the mixture in a twin-screw extruder, water-cooling and pelletizing, and vacuum drying to obtain the pipe lining resin. This invention improves the heat resistance and resistance to hot oil corrosion of the prepared pipe lining resin by limiting the amount of compatibilizer added to medium-density polyethylene and increasing the amount of nylon 6, while further improving its impact strength.

The invention discloses a high-performance and high-adaptability sheet which comprises an outer film, an upper lamination layer, a barrier layer, a lower lamination layer and an inner film which are sequentially connected from top to bottom in a composite mode. The outer film is formed by combining medium-density polyethylene and high-density polyethylene; the inner film is a curtain coating embossing inner film. According to the technical scheme, the condition of side seal wrinkles can be effectively reduced. In addition, the stiffness of the sheet is increased, after the sheet is made into a pipe and canned, the product is higher in overall hand feeling hardness, the product is higher in grade, and the overall quality of the product is improved. And the embossed inner film has excellent and comfortable hand feeling, so that a consumer feels more comfortable during use.

This invention discloses an anti-corrosion modified polyethylene coating for the surface of N-HAP hot-dip plastic-coated steel pipes and its preparation method, belonging to the field of coating technology. The invention comprises the following raw materials in parts by weight: 45-50 parts of synergistic microspheres, 30-32 parts of modified filler, 10-15 parts of nano-fumed silica, 1.5-2 parts of anhydrous ethanol, 50-60 parts of maleic anhydride-grafted polyethylene, 700-800 parts of medium-density polyethylene, 200-240 parts of high-density polyethylene, 100-120 parts of linear low-density polyethylene, 7-8 parts of antioxidant, 20-25 parts of polyethylene wax, and 15-20 parts of black masterbatch. The introduction of synergistic microspheres and modified filler effectively improves the wear resistance, corrosion resistance, scale resistance, and heat resistance of the anti-corrosion modified polyethylene coating for the surface of N-HAP hot-dip plastic-coated steel pipes. Therefore, this invention has a wider range of application prospects.