455 results about "Medium-density polyethylene" patented technology

A multilayer thin film is disclosed. The multilayer thin film has a thickness within the range of about 0.1 mil to about 1 mil and comprises at least one layer of a linear low density polyethylene (LLDPE) and at least one layer of a high density polyethylene (HDPE) or a medium density polyethylene (MDPE). The multilayer thin film has high tear strength and an excellent combination of other properties.

The invention relates to the technical field of heavy packaging membranes, in particular to a three-layer coextrusion heavy packaging membrane and a fabrication method thereof. An inner layer of the three-layer coextrusion heavy packaging membrane contains LLDPE (linear low density polyethylene) and m-LLDPE (metallocene-linear low density polyethylene); a middle layer thereof contains m-LLDPE, LLDPE, MDPE (medium density polyethylene), EVA (ethylene-vinyl acetate) and a color masterbatch; and an outer layer thereof contains LLDPE, LDPE (low density polyethylene) and m-LLDPE. The fabrication method of the three-layer coextrusion heavy packaging membrane adopts the proportioning, and a product is fabricated on a certain technological condition. Compared with the prior art, the membrane has the characteristics that the membrane is excellent in mechanical property and good in deflexion; a skin-friction coefficient of the membrane is moderate; and a heat-seal window can reach 180 minus/plus 50 DEG C. The membrane can fully meet the requirement of normal use of downstream packaging, is particularly suitable for high-speed FFS (form-fill-seal) packaging, and has a good economic benefit and a social benefit.

A method for making films is disclosed. The method comprises orienting in the machine direction a multilayer film at a draw-down ratio effective to give the film a dart-drop strength that increases with increasing draw-down ratio. The multilayer film comprises at least one layer of a linear low density polyethylene and at least one layer of a high density polyethylene or a medium density polyethylene.

The invention provides a composition and a method for preparing an ultrathin gas-permeable film. The gas-permeable film composition comprises a polyethylene blend, inorganic filler, a dispersant, an antioxidant and processing additives, wherein the polyethylene blend comprises medium-density polyethylene and linear low-density polyethylene, and can also comprise low-density polyethylene; the inorganic filler is micron or nano-scale calcium carbonate; and the dispersant is superfine fully-vulcanized powder rubber. The composition has better processing performance and mechanical properties, the casting and elongation rate are increased and meanwhile the gram weight can be further decreased to reduce the costs; the superfine fully-vulcanized powder rubber can assist the uniform dispersion of the inorganic filler in the resin so that the uniformity of the gas-permeable film is ensured.

The draw tape bag may include, a bag body defining a cavity and a rim, the rim defining a mouth to the bag. The bag may include a hem including a passageway, the hem defining at least one opening. The bag may further include at least one multilayer polyolefin draw tape disposed within the hem. The draw tape may include a first skin layer, a second skin layer, and at least one core layer disposed between the skin layers. The draw tape is machine direction oriented. The core layer may be located between the skin layers. The core layer may include high density polyethylene or medium density polyethylene. The skin layers may include low density polyethylene or linear low density polyethylene.

The invention discloses a high-strength and shock-resistance type metal ceramic composite lining plate and a preparation method thereof. The composite lining plate comprises, by mass, 20-80 parts of ceramic particles, 30-80 parts of metal powder, 30-50 parts of ultra-high molecular weight polyethylene, 5-10 parts of medium density polyethylene, 6-8 parts of low density polyethylene, 1-3 parts of magnesium hydroxide, 1-2 parts of diatomite, 10-15 parts of glass fibers, 0.5-1 part of dicumyl peroxide, 1-5 parts of coupling agent, 1-3 parts of antistatic agent, 1-3 parts of curing agent and 1-2 parts of addition agent. The preparation method includes the steps that the ceramic particles, the metal powder and the addition agent are mixed first so that a mixture A can be obtained; then the other components are mixed so that a mixture B can be obtained; afterwards, the mixture A and the mixture B are mixed, formed, sintered, quenched and tempered, and accordingly the composite lining plate is obtained. The metal ceramic composite lining plate has the characteristics of excellent abrasion resistance, impact resistance, chemical corrosion resistance and low-temperature toughness, and meanwhile has the characteristics of being good in processability and low in material cost.

A metallized, multilayer film suitable for packaging applications is provided which comprises a first skin layer comprising a thermoplastic selected from the group consisting of high density polyethylene, ethylene vinyl alcohol copolymer, medium density polyethylene, linear low density polyethylene, ethylene-propylene-butylene terpolymer, propylene-butylene copolymer, and amorphous polyamide, a metallized layer adjacent to the first skin layer, and a core layer comprising high crystallinity polypropylene homopolymer with an intermolecular stereoregularity greater than 93%. Additionally, low density polyethylene, EMA, EVA, or EAA may be extrusion laminated to the metallized side of the metallized, multilayer film at a web tension sufficient to prevent metal crazing of the vacuum deposited aluminum layer. A method for making the film is also provided.

The invention provides a PE film which is formed by co-extruding a corona layer, a middle layer and an inner layer. The corona layer comprises metallocene linear low density polyethylene resin and medium density polyethylene resin. The middle layer comprises low density polyethylene resin, linear low density polyethylene resin and medium density polyethylene resin. The inner layer comprises metallocene linear low density polyethylene resin and medium density polyethylene resin. The corona layer and the inner layer each comprises the high-proportion metallocene linear low density polyethylene resin, so that the PE film has good heat sealing performance, and the medium density polyethylene resin added in the corona layer, the middle layer and the inner layer enable the film to have good stiffness and flexibility, and the PE film is suitable for package of hygienic products.

The invention discloses a heat-shrinkable bus-bar protective sleeve comprising the following components in parts by weight: 100 parts of a resin substrate, 80-95 parts of a flame retardant, 2-5 parts of silicone master batch, 2-4 parts of a filler, 2.5-3.5 parts of a sensitizing agent, 4-5 parts of a color master batch, 2-4 parts of an antioxidant and 2-7 parts of a lubricating agent, wherein the resin substrate is one or a mixture of two or more of the following substances: linear low density polyethylene, medium density polyethylene, high density polyethylene, ethylene propylene rubber, a POE (Polyolefin Elastomer), a TPEE (Thermoplastic Polyether Ester Elastomer), an ethylene-vinyl acetate copolymer, an ethylene-methyl acrylate copolymer, an ethylene ethyl acrylate copolymer and an ethylene butyl acrylate copolymer; and the flame retardant is one or a mixture of two or more of the following substances: aluminum hydroxide, magnesium hydroxide, melamine cyanurate, ammonium polyphosphate and melamine pyrophosphate. The heat-shrinkable bus-bar protective sleeve disclosed by the invention is unlikely to age and crack and easy to install and replace.

It has been discovered that the properties of sheet or film materials of broad molecular weight distribution ethylene/propylene rubber impact-modified heterophasic copolymer (ICP) can be improved by blending the ICP with a second polyolefin. The second polyolefin may be a syndiotactic polypropylene (sPP), a random copolymer (RCP) of propylene and comonomer (e.g. ethylene and/or butene) made using a Ziegler-Natta or metallocene catalyst, medium density polyethylene (MDPE), linear low density polyethylene (LLDPE), or low crystalline copolymer of propylene/α-olefin. Improvements include, but are not necessarily limited to, reduced motor amps, lower secant modulus, increased dart drop strength, increased gloss, reduced haze, increased elongation to yield, elimination of stress whitening, improved puncture resistance, and decreased seal initiation temperature. This sheet of film materials may be co-extruded with other resins or laminated with other materials after extrusion.

Disclosed are polyethylene blends and films. The blend comprises from 1 to 99%, based on the weight of the blend, of a medium density polyethylene (MDPE) and from 1 to 99% a polyolefin selected from the group consisting of high density polyethylene (HDPE), linear low density polyethylene (LLDPE), low density polyethylene (LDPE), polypropylene, polybutene, and mixtures thereof. The MDPE is made by high pressure, free radical polymerization and has a density within the range of greater than 0.928 to 0.940 g/cm³ and an MI₂ within the range of 0.1 to 1 dg/min. The shrink films made from the blend have strong contraction force and low creep.

The invention relates to inorganic powder highly filled polyolefin decorative paper. The invention is characterized in that the decorative paper is composed of three-layer sheets or films which are formed by carrying out co-extrusion on raw materials containing 2-15% of HDPE (high density polyethylene), 4-15% of LLDPE (linear low density polyethylene), 3-12.7% of LDPE (low density polyethylene), 45-90% of inorganic powder, 0.1-5% of foaming microspheres, 0.1-0.3% of antioxidant and 0.2-13% of inorganic powder activator by virtue of a T-shaped mould of a three-layer co-extrusion film blowing machine, wherein at least one layer is a foaming body; the upper layer and the lower layer of the decorative paper respectively account for 15-20wt% of the decorative paper, the middle layer accounts for 60-70wt% of the decorative paper; and the grain size of the inorganic powder is 2-15 microns, and the density of the inorganic powder is 0.4-0.95g/cm<3>. The surfaces of the films and sheets prepared by the invention are soft and have elasticity, the paper texture is good, the mechanical strength is high, and the relative density is 0.5-0.95g/cm<3>; and the invention has the advantages that thedensity of the inorganic powder highly filled non-polyvinyl chloride (PVC) polymer decorative paper is greatly reduced, the problem of poor mechanical strength of the foaming sheets and films is solved by virtue of a multilayer co-extrusion process, and an obvious technical effect is achieved.

The invention discloses an ultra-thin resin foamed sheet as well as a production method and an application thereof. For the raw material, at least one of LLDPE (linear low density polyethylene), LDPE (low density polyethylene), MDPE (medium density polyethylene) and HDPE (high density polyethylene) is taken as the basic resin, an alkene thermoplastic elastomer or rubber is taken as a resin modifier, and the raw material further comprises a foaming agent and an antioxidant. The ultra-thin resin foamed sheet adopts a porous structure, the thickness is 0.04-0.3 mm, and the apparent density is 0.1-0.5 g/cm<3>; in the thickness direction, the ultra-thin resin foamed sheet comprises at least two bubbles and adopts a round or irregular oval structure. Compared with the conventional foamed sheet, the ultra-thin resin foamed material having irregular oval cellular structure as well as specific thickness and apparent density is thinner and lighter, is softer and lighter than a film material and is more suitable for thin and light sealing and cushioning materials or binding tape substrates of electronic equipment.

The invention discloses a polyethylene cable material. The polyethylene cable material is characterized by comprising the following components: 20 to 80 parts of linear low-density polyethylene, 20 to 80 parts of low density polyethylene, 1 to 5 parts of a catalyst--a dibutyl tin laurate compound, 1 to 3 parts of an anti-oxidant 300, 0.4 to 2 parts of a silicane cross-linking agent--vinyltrimethoxy silane, 0.01 to 0.04 part of an initiator--dicumyl peroxide and 1 to 4 parts of a water supplying agent. A preparation method for the polyethylene cable material comprises the following steps: preparing a catalyst master batch by extruding linear low density polyethylene, low density polyethylene, the anti-oxidant and the catalyst with a single screw; and putting linear low density polyethylene, low density polyethylene and the catalyst master batch in an enclosed mixer, carrying out vacuum-pumping and drying under a heating condition, then allowing the silicane cross-linking agent and the DCP initiator to penetrate into polyethylene through gasification, controlling the rotating speed and time of the enclosed mixer and carrying out discharging and vacuum packaging so as to obtain the one-step silicane cross-linked polyethylene cable material.

Disclosed herein is a backsheet for a solar module. The backsheet includes a first polymeric layer, a second polymeric layer and a moisture-resistant layer. The first polymeric layer includes linear low-density polyethylene (LLDPE), low-density polyethylene (LDPE), medium-density polyethylene (MDPE), high-density polyethylene (HDPE) or polycarbonate (PC). The second polymeric layer includes linear low-density polyethylene (LLDPE), low-density polyethylene (LDPE), medium-density polyethylene (MDPE), high-density polyethylene (HDPE), polycarbonate (PC) or Nylon. The moisture-resistant layer is disposed between the first polymeric layer and the second polymeric layer.

The invention discloses a special veneering pressing and sticking method of melamine impregnated paper, which comprises the steps of: softening medium density polyethylene fibreboards, improving the formula of the melamine impregnated paper, and compression-molding by adopting a concave and convex matching mould. The method avoids the deficiencies that a traditional door sheet is not wear-resistant, is not stain-resistant, is easy to deform, crack, delaminate, burn, and mildew, and the surface of a traditional door sheet needs cumbersome processing procedures, such as many times of painting or spray painting, and the like.

The invention provides a printable double-faced heat sealing film, a preparation method and an application thereof. The film sequentially comprises an outer layer, a middle layer and an inner layer, wherein the outer layer comprises the following raw materials in percentage by weight: 50-70% of first linear low density polyethylene, 15-25% of first low density polyethylene and 15-25% of first metallocene linear low density polyethylene; the middle layer comprises the following raw materials in percentage by weight: 70-80% of second linear low density polyethylene and 20-30% of medium density polyethylene; the inner layer comprises the following raw materials in percentage by weight: 40-60% of third linear low density polyethylene, 18-30% of second low density polyethylene and 18-30% of second metallocene linear low density polyethylene. The film has good double-faced heat sealing property. Meanwhile, after the resin materials in the layers of the thin are reasonably matched, the film further has printability.

The invention discloses a multilayer heat shrinkage film, which comprises a heat sealing layer, an outer layer and a middle layer, wherein the heat sealing layer is in contact with a packing object, the middle layer is connected with the outer layer and the heat sealing layer, the heat sealing layer comprises ultra-low-density polyethylene and one of materials or a mixture of more than one of materials selected from enhanced middle-density polyethylene, linear low-density polyethylene, low-density polyethylene, ethylene alpha-olefins plastic body copolymers, metallocene polyethylene and ethylene-ethylene vinyl acetate copolymers, and the outer layer comprises ethylene-ethylenepropylene polymers and one of materials or a mixture of more than one of materials selected from enhanced middle-density polyethylene, linear low-density polyethylene, low-density polyethylene, ethylene alpha-olefins plastic body copolymers, metallocene polyethylene and ethylene-ethylene vinyl acetate copolymers. Experiment results show that the multilayer heat shrinkage film prepared by the invention has a wider heat sealing temperature range, and in addition, the mechanical performance and the optical performance are good.

The invention discloses a material special for a corrugated pipe for high-density polyethylene (PE) prestressed concrete and a production method thereof. According to a raw material formula, the material comprises the following components in part by weight: 100 parts of recycled high-density polyethylene, 5 to 20 parts of mica powder, 0.1 to 0.5 part of silane coupling agent KH570, 1 to 6 parts of maleic anhydride grafted polyethylene, 1 to 3 parts of PE wax, 0. 3 to 1.5 parts of white mineral oil and 0.2 to 0.5 part of color master batch, and is prepared by the following steps of: adding the mica powder, the silane coupling agent and the PE wax into a high-speed mixer; mixing at the rotation speed of between 800 and 1,200r/min and the temperature of between 100 and 130 DEG C for 2 to 5 minutes to activate the surface of the mica powder so as to obtain uniformly dispersed powdery mixture; and adding the recycled high-density polyethylene and the like in turn. The material special for the corrugated pipe for the high-density polyethylene prestressed concrete is low in cost, has high strength and stable performance, and can meet the operating requirements of the fields of capital construction of concrete, such as bridges, long-span building and the like.

The present invention relates to a sheath material for an optical fiber cable, and a production process thereof. The sheath material comprises, by weight, 85-95% of a polyolefin base material, 2.35-2.85% of carbon black, 0.5-1% of an antioxidant, and 0.8-1% of an additive, wherein the polyolefin base material comprises a polyethylene base material and a modifier, and the additive comprises a fluorine-containing rheological agent PPA, a lubricant, a plastic brightening agent and a softener. During production, carbon black is made into a masterbatch; PPA is made into a masterbatch by using a polyethylene base material; the carbon black masterbatch, the PPA masterbatch, an antioxidant, a plastic brightening agent and a softener are mixed; the mixed material is added to EVA to mix; the resulting mixture is added to polyethylene to mix, and then mastication extrusion is performed through a plastic extruder. According to the present invention, high and medium density polyethylene is adopted as a base material for the optical fiber cable sheath, such that a chemical performance is stable; and various auxiliary materials are added to the polyethylene base material, such that performances of the optical fiber cable sheath are improved, and various use requirements of the optical fiber cables are met.

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.