1005 results about "Linear low-density polyethylene" patented technology

The invention discloses a high-strength polyethylene film and a preparation method thereof, and relates to the technical field of high polymer materials. The invention discloses a high-strength polyethylene film. The high-density polyethylene composite material is prepared from the following raw materials in parts by weight: 35 to 45 parts of high-density polyethylene, 25 to 35 parts of linear low-density polyethylene, 12 to 18 parts of ethylene-vinyl acetate copolymer, 5 to 10 parts of nano silicon dioxide, 3 to 7 parts of organic montmorillonite, 1.5 to 3.5 parts of hindered amine light stabilizer, 1.5 to 2.5 parts of antioxidant 1010, 0.8 to 1.2 parts of calcium stearate, 0.8 to 1.2 parts of zinc stearate, 0.8 to 1.2 parts of silane coupling agent and 4 to 6 parts of maleic anhydride grafted polyethylene. The composite material is prepared from the following components in parts by weight: 1.5-3.5 parts of a quaternized chitosan-nano silver compound, 6-9 parts of a modified toughening agent, 4-7 parts of a modified heat-resistant agent, 1.5-3.5 parts of a processing aid, 0.15-0.35 part of dibenzoyl peroxide and 0.5-1.5 parts of a nucleating agent DBS. The composite material is excellent in comprehensive performance, high in strength, good in flexibility and puncture resistance, excellent in aging resistance, heat resistance, chemical resistance and antibacterial property, good in processability, capable of meeting the requirements of multiple fields such as packaging and agriculture, scientific in preparation method and high in practical value.

The invention relates to the technical field of cables, and provides a fireproof flame-retardant 10kV power cable and a preparation method thereof. The fire-resistant flame-retardant 10kV power cable comprises a conductor and a fire-resistant flame-retardant layer, the fireproof flame-retardant layer is prepared from the following raw materials in parts by weight: 35 to 45 parts of linear low-density polyethylene, 40 to 50 parts of ethylene-vinyl acetate copolymer, 25 to 30 parts of modified aluminum hydroxide, 5 to 8 parts of polyethylene grafted maleic anhydride, 10 to 12 parts of phosphate modified halloysite nanotube, 5 to 8 parts of ZIF-8 loaded zinc borate core-shell particles, 15 to 20 parts of magnesium hydroxide and 2 to 3 parts of silane coupling agent. 0.5 to 1 part of antioxidant, 0.5 to 1 part of calcium stearate and 1 to 1.5 parts of polyethylene wax. According to the cable prepared in the invention, the situation that a conductor is exposed and the fire resistance is lost due to cracking and falling under long-time high-temperature baking is avoided; the continuous effectiveness of the flame retardant at high temperature is improved.

The invention relates to the technical field of packaging films, and particularly discloses a heat-resistant polyethylene composite packaging film and a preparation method thereof.The polyethylene composite packaging film comprises an inner layer, a middle layer and an outer layer, the inner layer is prepared from, by mass, 100 parts of linear low-density polyethylene, 28-32 parts of polypropylene and 8-10 parts of hydrotalcite modified blending materials, the middle layer comprises the following raw materials in parts by weight: 100 parts of low-density polyethylene, 40-60 parts of linear low-density polyethylene, 3-5 parts of a coupling agent and 0.5-1 part of an antioxidant, the outer layer comprises the following raw materials in parts by weight: 100 parts of modified PA6, 20-30 parts of metallocene polyethylene and 5-8 parts of a compatilizer, functional gradient distribution is realized by adopting layered extrusion of three-layer co-extrusion, and PA6 and polypropylene have a synergistic effect, so that the composite film has excellent heat resistance, and the service life of the composite film is prolonged. The hydrotalcite and the graphene oxide have a synergistic effect, the layered structure effectively obstructs oxygen and water vapor, and the obtained polyethylene composite packaging film is good in barrier property and has excellent mechanical property and heat resistance.

The invention discloses a rat-proof and termite-proof flame-retardant medium-voltage cable and a preparation method thereof, and belongs to the technical field of cables. The cable is composed of a conductor, a conductor shielding layer, an insulating layer, a metal shielding layer and a protective sleeve which are sequentially arranged from inside to outside. Linear low-density polyethylene is taken as a raw material of the protective sleeve material, and polyethylene molecular chains are mutually connected through irradiation crosslinking to form a three-dimensional network structure, so that the cable is endowed with excellent mechanical strength and excellent comprehensive performance; by modifying the nano silicon nitride, the agglomeration phenomenon is obviously reduced, the mechanical strength and wear resistance of the cable are enhanced, and the rat-proof and termite-proof effects of the cable are improved; the prepared multi-effect flame retardant contains multiple functional groups, can significantly enhance the flame retardance, mechanical strength and rat-proof and termite-proof effects of the cable, and has long and stable performance. Therefore, the prepared cable is high in mechanical strength and good in wear resistance, has stable and efficient flame retardance and rat-proof and termite-proof effects, and has important application value in the technical field of cables.

The invention belongs to the technical field of waterproofing of constructional engineering, and provides a high-strength puncture-resistant railway tunnel waterproof and drainage board and a preparation method thereof.The high-strength puncture-resistant railway tunnel waterproof and drainage board is prepared from, by mass, 30-35 wt% of polyolefin elastomer POE, 40-45 wt% of high-density polyethylene and 20-30 wt% of antioxidant enhanced master batch; the antioxidant enhanced master batch is prepared from the following components in parts by weight: 6 to 8 parts of nano SiO2, 20 to 28 parts of EPDM-g-MS, 60 to 70 parts of linear low-density polyethylene, 1 to 3 parts of an antioxidant and 1 to 3 parts of an anti-ultraviolet agent. The waterproof and drainage board for the railway tunnel, provided by the invention, not only meets all properties specified in Q / CR562.3-2018, but also has more excellent tensile property and puncture resistance.

The invention discloses an anti-freezing PE (polyethylene) film, a composite film of the anti-freezing PE film and a related preparation method, relates to the field of packaging films, and aims to solve the problem of low freezing resistance and puncture resistance in the prior art. Comprising anti-freezing layer components: low-density polyethylene, high-density polyethylene, metallocene linear low-density polyethylene resin, cold-resistant PA66 resin, composite phosphate, olefin block copolymer resin, a modified nanoscale silicon oxide coupling agent and a nanoparticle toughening agent, and barrier layer components: low-density polyethylene, linear low-density polyethylene and high-density polyethylene. The toughening heat-sealing layer comprises the following components: low-density polyethylene, sarin resin, metallocene linear low-density polyethylene resin, EVA (Ethylene Vinyl Acetate) modified bonding resin, a slipping agent, a nanoparticle toughening agent, a modified nanoscale silicon oxide coupling agent, dioctyl adipate and an antioxidant. The composite material can resist-38 DEG C ultra-low temperature freezing, and is puncture-resistant, cold-resistant and excellent in barrier property.

The present application relates to the field of polyethylene films, and particularly discloses a multifunctional polyethylene breathable film and a preparation method therefor. The multifunctional polyethylene breathable film comprises the following raw materials in percentage by weight: 15%-30% of linear low-density polyethylene, 15%-40% of metallocene linear low-density polyethylene, 5%-10% of low-density polyethylene, 30%-50% of breathable masterbatch, 2%-10% of antistatic masterbatch, 2%-10% of antibacterial masterbatch, 5%-10% of flame-retardant masterbatch, and 2%-5% of color masterbatch. The preparation method for the multifunctional polyethylene breathable film comprises the following steps: mixing linear low-density polyethylene, metallocene linear low-density polyethylene, low-density polyethylene, breathable masterbatch, antistatic masterbatch, antibacterial masterbatch, flame-retardant masterbatch, and color masterbatch according to a formula ratio, performing melt extrusion, performing blow molding, drawing and stretching to form a film, and performing corona treatment. The prepared breathable film not only has good breathability and mechanical properties, but also has excellent antistatic, flame-retardant and antibacterial functions.

The invention relates to the technical field of cable coating materials, and particularly discloses a B1-grade cable material as well as a preparation method and application thereof. The cable material provided by the invention comprises matrix resin, a compatilizer, a flame retardant, a lubricant, an antioxidant, a smoke suppression charring agent, nano silicon dioxide and a silane coupling agent, the matrix resin is a mixture of linear low density polyethylene resin, an ethylene-octylene copolymer, metallocene polyethylene and an ethylene-vinyl acetate copolymer; the flame retardant is a mixture of magnesium hydroxide, aluminum hydroxide and hydrotalcite; the smoke suppression charring agent is a mixture of hydrous magnesium silicate and modified montmorillonite; the silane coupling agent is a mixture of vinyl silane and diamino silane. According to the cable material provided by the invention, the specific matrix resin, the flame retardant, the smoke suppression charring agent and the silane coupling agent are combined with auxiliaries such as the compatilizer, the lubricant, the antioxidant and the nano silicon dioxide to serve as raw materials, so that the flame-retardant effect of the B1-grade cable material is greatly improved.

The invention relates to the technical field of wire and cable manufacturing, in particular to a high-flexibility low-smoke fire-fighting power cable and a preparation method thereof. The cable sequentially comprises a cable core, a shielding layer and an outer sheath layer from inside to outside, the outer sheath layer is prepared from the following preparation raw materials: 60 to 65 parts of methyl vinyl silicone rubber, 12 to 15 parts of ethylene propylene diene monomer, 8 to 10 parts of linear low-density polyethylene, 5 to 6 parts of cross-linking agent, 20 to 22 parts of flame retardant, 6 to 8 parts of reinforced flame-retardant filler, 20 to 25 parts of modified heat-conducting filler, 1.2 to 1.5 parts of coupling agent, 1.3 to 1.5 parts of antioxidant, 3 to 3.5 parts of lubricant, 2 to 2.5 parts of vulcanizing agent and 0.6 to 0.8 part of accelerant. The outer sheath layer of the high-flexibility low-smoke fire-fighting power cable prepared by the invention has excellent mechanical strength, toughness, heat-conducting property, high temperature resistance and flame retardant property, so that the high-flexibility low-smoke fire-fighting power cable has higher reliability and safety in fire-fighting power supply occasions.

The invention discloses a weather-resistant flame-retardant crosslinked polyethylene insulating material, a cable material and a preparation method. The weather-resistant flame-retardant crosslinked polyethylene insulating material comprises the following components in parts by mass: 60-70 parts of linear low-density polyethylene (LLDPE), 20-25 parts of low-density polyethylene (LDPE) and 15-20 parts of a copolymerization mixture, the copolymerization mixture is prepared from a styrene-ethylene / butylene-styrene block copolymer (SEBS) and styrene-ethylene / butylene-styrene block copolymer grafted maleic anhydride (SEBS-g-MAH). The cable material disclosed by the invention not only can give consideration to the flame-retardant characteristic and light aging resistance of a cable insulating material, but also can inhibit the damage of moisture to the insulating material under an alternating electric field, reduce the moisture entering the insulating material in a natural environment, and improve the water tree resistance of the material.

The invention relates to a high-strength polyethylene wrapping film, which is composed of an ABCBC five-layer composite structure, the A layer comprises linear low-density polyethylene, tackifying master batch and an elastomer; the layer B comprises linear low-density polyethylene, metallocene polyethylene and low-density polyethylene; and the layer C is made of linear low-density polyethylene. By optimizing the ratio of the linear low-density polyethylene to the additive among the layers, the vacuum degree of the preparation process and the cooling speed of the molten adhesive film on a cooling roller are improved, and the longitudinal and transverse tensile strength of the prepared polyethylene film is superior to that of the existing film. The prepared high-strength polyethylene wrapping film can be used in the field of heavy object packaging.

The invention discloses a novel double-layer protection waterproof bus, which belongs to the technical field of power transmission equipment, and comprises an aluminum pipe, a copper pipe, a conductor shielding layer, a main insulating layer, an insulating shielding layer, a grounding screen and a double-layer outer sheath, the inner layer sheath is prepared from 85 to 95 parts of linear low density polyethylene, 8 to 15 parts of ethylene-octylene elastomer, 2.3 to 2.7 parts of silane coupling agent, 0.12 to 0.15 part of initiator, 0.5 to 1 part of antioxidant, 1.2 to 1.5 parts of stearic acid, 3 to 3.5 parts of zinc oxide and 2.4 to 2.8 parts of catalyst; the outer sheath is prepared from 50 to 70 parts of linear low-density polyethylene, 40 to 60 parts of high-density polyethylene, 2.3 to 2.7 parts of a silane coupling agent, 0.12 to 0.15 part of an initiator, 2.5 to 3.0 parts of a water supply type antioxidant, 1.2 to 1.5 parts of zinc oxide and 2.4 to 2.8 parts of a catalyst; the invention further discloses a preparation method of the novel double-layer protection waterproof bus, and the double-layer outer sheath which is excellent in single-layer performance, good in compatibility between layers and strong in bonding force is extruded on the prefabricated bus through a co-extrusion and self-crosslinking method.

The invention belongs to the technical field of flame-retardant polypropylene, and particularly relates to flame-retardant polypropylene containing intumescent DOPO derivatives and a preparation method thereof.The flame-retardant polypropylene is prepared from, by mass, 100 parts of polypropylene, 15-25 parts of intumescent DOPO flame retardant shown in the formula I, 3-10 parts of linear low-density polyethylene and 2-8 parts of silane coupling agent modified glass fiber, 1-8 parts of nano calcium carbonate; the total mass part of the silane coupling agent modified glass fiber and the nano calcium carbonate is 4-10. The novel intumescent DOPO flame retardant is prepared through synthesis, has an N and P synergistic flame retardant effect, and can enable polyolefin to have a very good flame retardant effect under the condition of a relatively low addition amount. Meanwhile, a certain amount of linear low-density polyethylene, silane coupling agent modified glass fiber and nano calcium carbonate are added in a matched manner, so that the mechanical property of polypropylene is improved, and particularly the impact property is remarkably improved.

The invention relates to the technical field of cables, and provides a high-temperature-resistant flame-retardant power cable and a preparation method thereof. A high-temperature-resistant flame-retardant power cable comprises a conductor and a high-temperature-resistant flame-retardant outer layer wrapping the conductor. The high-temperature-resistant flame-retardant outer layer is prepared from the following raw materials in parts by weight: linear low-density polyethylene, an ethylene-vinyl acetate copolymer, ethylene propylene diene monomer, chopped polyimide fibers, nano-coated magnesium hydroxide, zinc borate, zinc stannate, polyethylene grafted maleic anhydride, an anti-aging agent, dicumyl peroxide, an antioxidant, polyethylene wax, calcium stearate and cerium dioxide. According to the cable prepared in the invention, the reliability of an existing high-temperature-resistant flame-retardant power cable under thermal cycle is improved, and the problem of local temperature resistance difference caused by agglomeration and high-temperature migration of nanoparticles in a polymer matrix is improved.

The invention provides a flame-retardant polyolefin composition as well as a preparation method and application thereof, and the flame-retardant polyolefin composition comprises the following components in parts by weight: 13-22 parts of an ethylene-vinyl acetate copolymer, 1.5-8.5 parts of linear low density polyethylene, 8-17 parts of a polyolefin elastomer, 35-55 parts of a flame retardant and 0.5-2.5 parts of an antioxidant. The antioxidant comprises a main antioxidant and an auxiliary antioxidant; the main antioxidant comprises a hindered phenol antioxidant and an amine antioxidant; and the auxiliary antioxidant comprises a thioester antioxidant and / or a phosphite ester antioxidant. According to the flame-retardant polyolefin composition disclosed by the invention, the ethylene-vinyl acetate copolymer, the linear low-density polyethylene and the polyolefin elastomer are compounded according to a specific content, and meanwhile, the antioxidant with specific composition is matched, so that the flame-retardant polyolefin composition is good in heat resistance, aging resistance and precipitation resistance; meanwhile, the mechanical property is good.

The invention discloses a halogen-free flame-retardant reinforced PPE / PA6 composition with a high CTI (comparative tracking index) value and a preparation method of the halogen-free flame-retardant reinforced PPE / PA6 composition. The halogen-free flame-retardant reinforced PPE / PA6 composition comprises the following raw materials in percentage by mass: 7%-30% of high-fluidity PPE, 20%-40% of high-fluidity PA6, 3%-10% of a toughening agent, 4%-8% of a halogen-free flame retardant, 3%-7% of a compatilizer, 20%-50% of glass fibers, 2%-5% of a CTI (comparative tracking index) enhancing aid, 1.3%-1.7% of linear low-density polyethylene and 1%-5% of other aids. The halogen-free flame-retardant reinforced PPE / PA6 alloy material provided by the invention has an excellent CTI (Comparative Tracking Index) value (700V) and good flame retardance (1.6 mm-V0), and can be applied to new energy automobile battery components, electronic appliances and the like.

The invention relates to the technical field of wire and cable preparation, and discloses a flame-retardant anti-aging wire and cable and a preparation method thereof. The preparation method of the flame-retardant anti-aging wire and cable comprises the following steps: reacting a ketal compound with thionyl chloride, and then reacting with ricinoleic acid ester to obtain an intermediate product; reacting the thiazolopyridyl compound with the intermediate product to obtain a bio-based plasticizer; modifying the bio-based plasticizer to obtain a modified bio-based plasticizer; mixing polyvinyl chloride resin, linear low-density polyethylene, an ethylene-octylene copolymer, a flame-retardant anti-aging agent, a modified bio-based plasticizer and other components to obtain a sheath layer mixed master batch, and extruding to obtain a sheath layer; and after coating the conductor with the sheath layer, cooling, rolling and packaging to obtain the flame-retardant anti-aging wire and cable. The flame-retardant anti-aging wire and cable sheath layer has good flame retardance, aging resistance and mechanical property, and plays a good role in protecting wires and cables.

The invention discloses a large-current-carrying-capacity flexible power cable, which belongs to the technical field of cable preparation, is used for solving the technical problem that the flame retardant property and the mechanical property of the power cable need to be further improved in the prior art, and specifically comprises a cable core, a wrapping layer, an insulating layer and a sheath layer which are sequentially arranged from inside to outside. The preparation method comprises the following steps: preparing alkoxy silane containing a benzocyclobutene group, preparing flame-retardant particles by using a sol-gel method, preparing modified polyurethane by using modified polysiloxane and 2, 5-furandimethanol as soft segments, naphthalene diisocyanate as a hard segment and trimethylolpropane as a chain extender, and preparing the flame-retardant flame-retardant polyurethane. The linear low-density polyethylene, the MAH-g-PE, the modified polyurethane, the flame-retardant particles and the auxiliary additive are melted and extruded outside the wire core to form the insulating layer, so that the power cable is obtained, the flame-retardant property of the power cable is effectively improved, and the mechanical property and the current-carrying stability of the power cable are also improved.

Disclosed in the present invention are a 90°C thermoplastic halogen-free low-smoke flame-retardant polyolefin sheath material and a preparation method therefor. The sheath material is prepared from raw materials comprising the following components in parts by mass: 20-40 parts of an ethylene-vinyl acetate copolymer, 20-40 parts of a linear low-density polyethylene, 2-10 parts of a high-density polyethylene, 20-40 parts of a metallocene ethylene-octylene copolymer, 10-15 parts of a maleic-anhydride-grafted metallocene linear low-density polyethylene copolymer, 58-73 parts of aluminum hydroxide, 20-25 parts of modified magnesium hydroxide, 64-84 parts of a synergistic flame retardant, 2-3 parts of a coupling agent, 1-4 parts of a lubricant, 1-3 parts of an antioxidant, and 2-7 parts of a coloring agent, wherein the synergistic flame retardant comprises lithium oxide. A matrix resin has low-temperature performance, mechanical properties and cracking resistance. With regard to flame retardance, a large amount of the synergistic flame retardant, i.e., lithium oxide, is added to a traditional magnesium-aluminum compound flame-retardant system, and therefore an off-white hard shell can be formed during a combustion process while low heat release is ensured, thereby ensuring no dripping during the combustion process.

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.

These polypropylene resin foam particles each have a foam core layer composed of a polypropylene resin, and a coating layer covering the foam core layer. The coating layer is composed of linear low-density polyethylene. The mass ratio of the coating layer to the foam core layer is 0.005-0.05. The polypropylene resin constituting the foam core layer satisfies a prescribed condition (i) or (ii). Said foam particles can remarkably reduce the steam pressure at the time of in-mold molding, can shorten the curing time, and furthermore makes it possible to obtain a foam particle molded article that has a desired shape and is excellent in appearance even when the curing time is shortened.

The invention relates to the technical field of cables, and particularly discloses an anti-interference control cable. The anti-interference control cable comprises a plurality of cable cores, a glass fiber tape wrapping layer, a glass fiber filler, an inner copper-plastic composite tape shielding layer, an aluminum wire braided shielding layer, an outer copper-plastic composite tape shielding layer, a mica tape wrapping layer and a sheath layer. The sheath layer is formed by extruding and processing a flame-retardant cross-linked polyethylene material; the flame-retardant crosslinked polyethylene material is mainly prepared from the following raw materials: a linear low-density polyethylene prepolymer, an ethylene-vinyl acetate prepolymer, maleic anhydride grafted polyethylene, stearic acid, a modified hyperbranched amide polymer, a crosslinking agent, an antioxidant, an ultraviolet light absorber and a flame retardant. The flame-retardant crosslinked polyethylene material has the characteristics of high tensile strength and good aging resistance. The anti-interference control cable has the characteristics of strong anti-electromagnetic interference capability, good flame retardance and good aging resistance, shows excellent comprehensive performance, improves safety and reliability, and meets market requirements.

The present invention relates to a weather-resistant and anti-aging polyethylene pipeline and a preparation method thereof, and belongs to the technical field of polymer materials. The pipeline adopts high-density polyethylene resin, linear low-density polyethylene resin, polyimide resin powder, nano silicon dioxide, nano hexagonal boron nitride, polybenzimidazole fiber, carnosic acid, zinc glycyrrhetinate, antioxidant 1010, hindered amine light stabilizer, polydimethylsiloxane titanate cross-linked polymer, 3-methacryloxypropyl triethoxysilane as raw materials; wherein, polyimide resin powder, carnosic acid and zinc glycyrrhetinate are uniformly mixed, and then modified at 300°C to 350°C for 30min to 60min to obtain a modified product, which can better improve the weather resistance and aging resistance of the pipeline. Each component is compatible with each other, and a special modified preparation method is adopted to better play the synergistic effect of the components, and greatly improve the weather resistance and aging resistance of the polyethylene pipeline.

The invention relates to the technical field of cables, and provides a 10kV flame-retardant wire cable and a preparation method thereof. The 10kV flame-retardant wire cable comprises a bunched wire core and an outer sheath layer, the outer sheath layer is prepared from the following raw materials in parts by weight: 40 to 50 parts of linear low-density polyethylene, 30 to 40 parts of ethylene-vinyl acetate copolymer, 18 to 20 parts of microencapsulated ammonium polyphosphate, 6 to 8 parts of organic modified nano montmorillonite, 4 to 6 parts of zinc borate, 1 to 2 parts of silane coupling agent, 0.5 to 1 part of antioxidant and 0.4 to 0.6 part of calcium stearate. According to the 10 kV flame-retardant electric wire and cable prepared in the invention, the flame-retardant grade of the flame-retardant electric wire and cable is improved, but the problem that the elongation at break of the material is reduced due to excessive addition of the inorganic flame retardant is solved; and the problems of environmental adaptability and mechanical performance of sheath cracking easily caused by insufficient bending radius of the cable are improved.

The present invention relates to an olefin-based polymer, a film made therefrom, and a method for producing the same. The olefin-based polymer according to a specific example of the present invention has excellent processability, and the film made therefrom, particularly a linear low-density polyethylene film, has excellent mechanical strength, particularly impact strength.

Provided are linear low density polyethylene (LLDPE) compositions including a LLDPE polymer and from 100 ppm to 10,000 ppm of a polymer processing aid (PPA) that is substantially free of fluorine-containing compounds. The non-fluorine-containing inventive PPAs may be a polyphosphite, a polysiloxane, a polyethylene glycol, a high MFR polypropylene, a high MFR polybutene-1, a metal salt of a fatty acid, a polyamide, or a boron nitride. Also provided are polyolefin masterbatches including from 1 wt. % to 50 wt. % of such inventive PPAs and methods of decreasing melt fracture % in linear low density polyethylene films by blending such inventive PPAs and polyolefin masterbatches into cast films and blown films during extrusion processing.

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 relates to the technical field of flame-retardant materials, in particular to a halogen-free low-smoke flame-retardant material and a preparation process thereof. The halogen-free low-smoke flame-retardant material is prepared from the following raw materials: an ethylene-vinyl acetate copolymer, linear low-density polyethylene, maleic anhydride grafted modified polyethylene, a composite flame retardant, magnesium hydroxide, a synergistic flame retardant, an interface modifier and the like. The composite flame retardant is prepared from a sulfydryl-containing silane coupling agent, aluminum hydroxide and vinyl acetate. A composite flame retardant is prepared from a mercapto silane coupling agent, aluminum hydroxide and vinyl acetate as raw materials, the composite flame retardant is introduced into a material system, the dispersity and compatibility of inorganic filler in a polymer group are improved, a more continuous cross-linked network structure is formed, high-speed dry mixing, melt mixing and extrusion molding by a double-shaft eccentric rotor extruder are adopted, and the flame-retardant composite material is prepared. The processability of the material and the quality of a final product are improved, and the flame retardant property of the material is improved through the synergistic effect of the synergistic flame retardant.

The invention belongs to the technical field of waterproof and drainage boards, and provides a waterproof and drainage board with high compressive strength and tensile strength and a preparation method and application thereof.The waterproof and drainage board is formed by compounding an upper layer, a middle layer and a lower layer, and the upper layer and the lower layer are each prepared from 30-40 parts of high-density polyethylene, 10-20 parts of chlorinated polypropylene, 10-15 parts of metallocene polyethylene and 1-3 parts of carbon nanotubes; 2-5 parts of nano calcium carbonate, 1-5 parts of polyethylene wax, 1-3 parts of an antioxidant and 1-3 parts of an anti-ultraviolet agent; the middle layer is prepared from the following raw materials: 35 to 55 parts of linear low-density polyethylene, 15 to 30 parts of metallocene polyethylene, 10 to 15 parts of ethylene-vinyl acetate copolymer, 5 to 10 parts of POE (Polyolefin Elastomer), 5 to 10 parts of aramid chopped fiber, 1 to 3 parts of antioxidant and 1 to 3 parts of ultraviolet screening agent; the nano calcium carbonate is subjected to modification treatment. The waterproof and drainage board has relatively high compressive strength and tensile strength, and has a good application prospect.

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.