376 results about "Polyethylene membrane" patented technology

A multi-layer, microporous polyethylene membrane having at least three layers comprising (a) a first microporous layer amount of a polyethylene resin and constituting at least both surface layers, and (b) at least one second microporous layer made of a polyethylene resin, a heat-resistant resin having a melting point or glass transition temperature of 150° C. or higher and a filler, and sandwiched by both surface layers.

A multi-layer, microporous polyethylene membrane comprising (a) a first microporous layer made of a polyethylene resin, and (b) a second microporous layer comprising a polyethylene resin, and a heat-resistant polymer having a melting point or a glass transition temperature of 170° C. or higher, the heat-resistant polymer being dispersed in the form of fine particles in the polyethylene resin, and the second microporous layer having pores containing fine particles of the heat-resistant polymer as nuclei from which the cleavage of polyethylene resin fibrils starts, the multi-layer microporous polyethylene membrane having well-balanced shutdown properties, meltdown properties, permeability, mechanical strength, heat shrinkage resistance and compression resistance.

A microporous polyethylene membrane made of a polyethylene resin comprising 15% or less by mass of ultra-high-molecular-weight polyethylene having a mass-average molecular weight of 1×10⁶ or more, which is constituted by a dense-structure layer having an average pore diameter of 0.01 to 0.05 μm, and a coarse-structure layer formed on at least one surface and having an average pore diameter 1.2-fold to 5.0-fold of that of the dense-structure layer, has a high electrolytic solution absorption speed with thickness and air permeability little changing when compressed. Such a microporous polyethylene membrane is produced by extruding a melt blend of the above polyethylene resin and a membrane-forming solvent through a die, cooling the resultant extrudate with a temperature distribution in a thickness direction to provide a gel-like sheet, stretching the gel-like sheet at a temperature from the crystal dispersion temperature of the polyethylene resin +10° C. to the crystal dispersion temperature +30° C., removing the membrane-forming solvent, and stretching the membrane again to 1.05-fold to 1.45-fold.

The invention relates to low-frequency sound absorption needling non-woven composite materials and a preparation method of the low-frequency sound absorption needling non-woven composite materials and application of the low-frequency sound absorption needling non-woven composite materials. The composite materials comprise kapok fibers or hollow Dacron non-woven fabric and polyethylene films. The preparation method comprises: mixing, opening, carding and meshing are conducted to 60%-90% kapok fibers and 40%-10% hollow Dacron non-woven fabric according to mass percent; a fiber mesh is inputted in a needling machine so as to conduct needling reinforcement, the fiber mesh is reeled and cut off so as to obtain kapok or hollow Dacron needle non-woven fabric; the polyethylene films in 0.06mm-0.10mm are smoothly placed on one side of the needle non-woven fiber mesh, and are composited, taken out and cooled, and then the low-frequency sound absorption needling non-woven composite materials are obtained. The composite materials can be applied to the field of automotive trim, construction, high-speed rail and the like. The sound absorption materials have the advantages of being light in weight, simple in operation of the preparation method, good in economic benefit and suitable for industrial production.

The invention discloses a self-lubricating polyethylene membrane. The membrane consists of an outer layer, an intermediate layer and an inner layer, wherein the outer layer contains low density polyethylene and linear low density polyethylene with a weight ratio of 1:0.5-2; the intermediate layer contains low density polyethylene and linear low density polyethylene with a weight ratio of 1:0.5-5; and the inner layer contains low density polyethylene, linear low density polyethylene, metallocene linear low density polyethylene, a slipping agent and an auxiliary agent with a weight ratio of 1:0.5-2:1-2:0.01-0.02:0.05-0.2. Compared with the prior art, the self-lubricating polyethylene membrane has precise and stable friction coefficient and good transparency and lustrousness, and can realize matched packaging effect with a quick automatic packaging machine.

A multi-layer, microporous polyethylene membrane having at least two layers, which comprises (a) a microporous polyethylene resin layer A comprising high-density polyethylene A having 0.2 or more terminal vinyl groups per 10,000 carbon atoms when measured by infrared spectroscopy, and (b) a microporous polyethylene resin layer B comprising high-density polyethylene B having less than 0.2 terminal vinyl groups per 10,000 carbon atoms when measured by infrared spectroscopy, has well-balanced permeability, mechanical strength, heat shrinkage resistance, shutdown properties, meltdown properties and oxidation resistance.

The invention provides a polyethylene film resistant to high-temperature steaming and a production process of the polyethylene film. The polyethylene film comprises a corona layer, a middle layer and a heat sealing layer, wherein raw materials of the corona layer, the middle layer and the heat sealing layer comprise metallocene medium-density polyethylene and metallocene high-density polyethylene independently; the difference between the vicat softening point and the melting point of each of metallocene medium-density polyethylene and metallocene high-density polyethylene does not exceed 10 DEG C. The polyethylene film has high mechanical strength, excellent optical performance, low-temperature freezing performance, high heat-sealing strength, high thermo-viscous force, a wide heat-sealing window, low odor, resistance to steaming for 30 min at the temperature of 121 DEG C and other excellent performance and can be used as an inner material of a composite film resistant to high-temperature steaming.

The invention relates to a porous membrane having a particle filtration value of at least 10 under U.S. Military Standard MIL-STD-282 (1956), where the porous membrane is a polyethylene membrane. The membranes according to the invention are particularly useful for filters such as ASHRAE filters, HEPA filters and ULPA filters for example in heating, ventilating, respirators and air conditioning applications.

The invention discloses a high-temperature steaming resistant and easy-uncovered composite film. The film comprises a surface layer, a barrier layer and a heat sealing layer arranged in sequence; thesurface layer is a single-layer structure or two-layer composite structure or a three-layer composite structure, and comprises a PET film, a nylon film or a polypropylene film; the barrier layer is aluminum foil or aluminized PET; and the heat sealing layer is an inorganic filler modified polyethylene film. The invention also discloses a manufacturing method of the high-temperature steaming resistant and easy-uncovered composite film. The film of the invention can be subjected to high-temperature steaming sterilization, has good transparency, a wide heat sealing window, stable heat sealing strength and excellent uncovering property, and can meet safety performance requirements of medical packaging. After reaching the heat sealing window, the film of the invention does not cause dead sealing compared with a conventional film.

The invention provides a photoresponse block liquid crystal polymer with crosslinkable property and a preparation method thereof. The preparation method of the photoresponse block liquid crystal polymer is not limited by the dimension of a liquid crystal box, thereby being simpler and easier to operate on the aspect of the processing forming of the photoresponse block liquid crystal polymer; and in addition, the invention is not only beneficial to the preparation of large-size membranous materials, but also easy to realize the composite processing with flexible membranes, i.e. polyethylene membranes and the like, greatly enhances the mechanical property of the materials and is beneficial to the development of the photoresponse block liquid crystal polymer as an all-optical driving flexible device.

The invention relates to a fabricating method of air vent vehicle body paste, which mainly comprises the following steps: putting base paper on a membrane pouring machine frame; pouring a polyethylene membrane on the base paper at high temperature to form membrane poured paper; extruding leather patterns with regular tongues on the membrane poured paper to form embossing membrane poured paper; coating liquid organic silicone on the embossing membrane poured paper, making embossing release paper; coating glue water on the embossing release paper after being coated with the silicone; drying the embossing release paper after being coated with the glue water through an oven; jointing a PVC membrane on the embossing release paper through a cooling and jointing roll; and rolling, cutting and packaging after the jointing. The air vent vehicle body paste fabricated by the method can guide gathered air without air bubbles through leather patterned tongues during jointing and using, is convenient for construction, and is flat and beautiful in pictures.

A multi-layer, microporous polyolefin membrane comprising a polypropylene layer and a polyethylene resin layer and having well-balanced permeability, mechanical strength, heat shrinkage resistance, shutdown properties and meltdown properties can be obtained by (1) forming a sheet comprising a gel-like polypropylene layer containing a membrane-forming solvent or a polypropylene layer containing no membrane-forming solvent and a gel-like polyethylene resin layer containing a membrane-forming solvent, stretching the sheet at two-stage temperatures, and then removing the membrane-forming solvent, or (2) forming a gel-like polypropylene sheet containing a membrane-forming solvent or a polypropylene sheet containing no membrane-forming solvent, and a gel-like polyethylene resin sheet containing a membrane-forming solvent, stretching them at two-stage temperatures, removing the membrane-forming solvent, and then laminating the resultant microporous polypropylene membrane and the resultant microporous polyethylene membrane.

A preparation method of a calcium carbonate-filled high-performance degradable polyethylene film comprises the following steps: 1, drying calcium carbonate; 2, fully mixing dried calcium carbonate with a coupling agent according to a mass ratio of 100:0.5-3; 3, fully mixing high density polyethylene, EVA and calcium carbonate obtained in step 2; 4, adding a photodegradation agent to a mixture obtained in step 3, and uniformly mixing; 5, adding a mixture obtained in step 4 to an extruder, and carrying out fusing extrusion and granulation; and 6, adding granules obtained in step 5 to a film blowing machine, and carrying out blow molding to form the film. The polyethylene film prepared in the invention has the advantages of low cost, good mechanical performances, high tensile strength and elongation at break, degradability and environmental protection.

The invention provides a preparation method of a standard sample for the specific migration quantity detection on restricted substances in a polyethylene film. The preparation method comprises the following steps: uniformly mixing specific migration substances and a blow molding grade polyethylene resin raw material, and manufacturing master batches by using a double-screw extruder; then mixing the master batches and the polyethylene resin raw material in a set proportion, regulating the pulling speed by using a blow molding machine to obtain the polyethylene film with a certain thickness, and carrying out series treatment on the film to obtain the standard sample. The standard sample has the good uniformity and stability, can be used for comparing interlaboratory specific migration quantity detection data of the restricted substances in the polyethylene film, verifying the accuracy of the method, calibrating test instruments, controlling the quality and assessing test results. The preparation method is low in material cost and simple; the obtained standard sample is a material standard sample, is uniform and stable, and is easy to store.

The invention relates to a material special for preparing a lithium ion battery diaphragm and a preparation method thereof. The material consists of the following components in part by weight: 62.5 to 86 parts of polyethylene, 0.5 to 1.5 parts of di-tert-butyl peroxide, 3 to 5 parts of vinyl triethoxy silane, 10 to 30 parts of titanium dioxide whiskers and 0.5 to 1 part of antioxidant. The preparation method comprises the following steps of: mixing the polyethylene, the di-tert-butyl peroxide, the antioxidant and the vinyl triethoxy silane, performing melt blending by using a double-screw extruder and performing an in-situ grafting reaction to obtain silane-grafted polyethylene; and stirring and blending the silane-grafted polyethylene and the titanium dioxide whiskers to obtain the material special for preparing the lithium ion battery diaphragm. The vinyl triethoxy silane is grafted on a polyethylene molecular chain and an ethyoxyl silane group can further react with the titanium dioxide whiskers so that a cross-linking reaction is realized in an entire membrane system and the intensity of a polyethylene membrane is enhanced.

The invention discloses a formation method of a nano coating of a lithium ion battery membrane. The formation method comprises the following steps: (1) dissolving an aqueous adhesive and an additive into de-ionized water and stirring for 3h to obtain an aqueous adhesive mixed solution; (2) adding an inorganic material nano-sol into the aqueous adhesive mixed solution; continually stirring for 2h and standing for 1h to obtain aqueous nano coating paint; (3) putting a polyethylene membrane into a plasma treatment device for treating, so as to primarily improve the surface of the membrane; then coating the surface of the lithium ion battery membrane and the surface of a three-dimensional pore channel with the aqueous nano coating paint; drying the coated membrane in the air for 10min and then transferring the membrane into a drying box at 40 DEG C; drying to obtain the lithium ion battery membrane modified by a nano inorganic coating. The battery membrane disclosed by the invention can be used for modifying the surface of the membrane and the pore channel under the condition that the thickness of the membrane is not increased; the speed of ions penetrating through the membrane is improved, and the ion conductivity and the lithium-ion transference number of the membrane are improved; when the modified membrane is used for assembling a battery, the circulating performance of the battery is remarkably improved.

The invention belongs to the technical field of grain storage, and in particular relates to an underground bionic honeycomb granary and a grain storage method. The granary is designed through the reference and absorption of the original ecological honeycomb structure principle and comprises a granary body positioned below the ground surface, wherein the granary body consists of a plurality of rows of honeycomb silos among which gaps are formed in the transverse direction; each row of honeycomb silo comprises a plurality of silos which are tightly arranged along the longitudinal direction in turn; a silo upper opening is formed at the upper end of each silo and is provided with a closed cover; each silo comprises a reinforced concrete layer or a brick-concrete masonry layer; a polyethylenefilm layer is arranged in each silo; a spodosol layer is backfilled in an outer wall gap of each silo; and soil or sandstone or a soil and sandstone mixed material is backfilled among the spodosol layers. Grain is stored in the polyethylene film layers and isolated from outside, so that four ecological factors such as moisture, temperature, oxygen and light rays which can cause the deterioration of the stored grain are inhibited from the source, the stored grain is free from insects, mildew, rat damage, fires, floods and earthquakes, and the shelf life of the stored grain is prolonged by morethan one time.