77 results about "Die swell" patented technology

The present invention relates to a polyolefin that has high environmental stress cracking resistance (ESCR), a high impact property, and an excellent die swell property, and a method of preparing the same. According to the method of preparing polyolefin of the present invention, a supported hybrid metallocene catalyst and an alpha olefin comonomer having 4 or more carbon atoms are used to obtain polyolefin having the bimodal or multimodal molecular weight distribution curves during the single reactor polymerization. The polyolefin has excellent processability, a melt flow rate ratio (MFRR) that is useful to processing, excellent shapability, impact strength, tensile strength, in particular, environmental stress cracking resistance (ESCR) and full notch creep test (FNCT), thus being used to manufacture the blow molded product.

A butyl polymer having improved processability is described, together with a process for production thereof. The butyl polymer derived from a reaction mixture which contains: (i) a monomer mixture comprising a C4 to C7 monoolefin monomer (preferably isobutylene) and a C4 to C14 multiolefin monomer (preferably isoprene); (ii) a multiolefin cross-linking agent (preferably divinyl benzene); and (iii) a chain transfer agent (preferably diisobutylene (2,2,4-trimethyl-1-pentene)). The subject butyl polymer has an improved balance of cold flow, filler dispersion, extrusion rate and die swell.

Bimodal polyethylene compositions and blow molded bottles made therefrom are provided. In at least one specific embodiment, the composition includes at least one high molecular weight polyethylene component having a molecular weight distribution (MWD) of about 6 to about 9, a short chain branch content of less than about 2 branches per 1,000 main chain carbons, and a Mz of about 1,100,000 or more. The composition also includes at least one low molecular weight polyethylene component where a ratio of weight average molecular weight of the high molecular weight polyethylene component to weight average molecular weight of the low molecular weight polyethylene component is about 20 or less. The polyethylene composition has a density of about 0.94 g/cc or more, an ESCR of about 600 hours or more, a percent die swell of about 70% or more, and may comprise at least 70% ethylene-derived units.

Bimodal polyethylene compositions and methods for making the same are provided. In at least one specific embodiment, the bimodal polyethylene composition can include a high molecular weight component having a weight average molecular weight (Mw) of from about 400,000 to about 950,000. The bimodal polyethylene composition can also include a low molecular weight component having a weight average molecular weight (Mw) of from about 3,000 to about 100,000. The high molecular weight component can be present in an amount ranging from about 25 wt % to about 40 wt % of the bimodal polyethylene composition. The bimodal polyethylene composition can also have a percent die swell of less than about 80%.

Bimodal polyethylene compositions and blow molded bottles made therefrom are provided. In at least one specific embodiment, the composition includes at least one high molecular weight polyethylene component having a molecular weight distribution (MWD) of about 6 to about 9, a short chain branch content of less than about 2 branches per 1,000 main chain carbons, and a Mz of about 1,100,000 or more. The composition also includes at least one low molecular weight polyethylene component where a ratio of weight average molecular weight of the high molecular weight polyethylene component to weight average molecular weight of the low molecular weight polyethylene component is about 20 or less. The composition has a density of about 0.94 g/cc or more, an ESCR of about 600 hours or more, and a percent die swell of about 70% or more.

The invention provides a polypropylene based resin composition, which has good moldability on injection molding and which is excellent in its flow mark appearance as well as weld appearance on molding, and suitable for injection-molded articles such as exterior parts of automobiles, and also provides a moldability modifier used for the composition.

The invention is a moldability modifier for a polypropylene based resin, which comprises at least one of a propylene homopolymer and a propylene random polymer having die swell ratio of 1.5 to 2.5 and ratio (Q value: Mw/Mn) of 7 to 13 of the weight average molecular weight (Mw) to the number average molecular weight (Mn) measured by gel permeation chromatography (GPC). The moldability modifier is mixed with a propylene-ethylene block copolymer, an ethylenic or styrenic elastomer, an inorganic filler, etc. to prepare a polypropylene based resin composition.

The invention relates to plywood and a manufacturing method of the plywood, and discloses wood plastic composite material veneering plywood and a manufacturing method and application of the wood plastic composite material veneering plywood. The wood plastic composite material veneering plywood aims to solve the problems that when wooden plywood manufactured according to an existing method is used, a die swells easily, the die is released difficultly, the number of turnover using times is small, and the wood plastic composite board cannot be easily used as a building formwork independently. The wood plastic composite material veneering plywood is formed by a wood plastic composite sheet, a non-woven fabric, wood plywood and adhesives in a manufactured mode. The manufacturing method comprises the steps that the wood plastic composite sheet is manufactured; a non-woven fabric cladding wood plastic composite material is manufactured; the plywood is preprocessed; the adhesives are coated; pre-pressing is carried out; hot pressing is carried out. The wood plastic composite material veneering plywood can be used as the building formwork. The wood plastic composite material veneering plywood has the advantages that the formwork and concrete are separated easily, a casting surface is flat and smooth, and labor intensity of die unloading is relieved; the number of turnover using times of the formwork is improved to be 50-70; weight is light and intensity is high.

The invention discloses a chain type staggered micro-channel structure. The chain type staggered micro-channel structure comprises a substrate and micro fluid passageways arranged on the substrate. The chain type staggered micro-channel structure is characterized in that each micro fluid passageway comprises two branch micro fluid passageway bodies which intersect and are separated in a periodic mode, intersections are formed in the positions where the branch micro fluid passageway bodies intersect, and furcation openings are formed in the positions where the branch micro fluid passageway bodies are separated. According to the micro fluid passageways, the bent micro passageways are arc type channels periodically changing and are formed by smoothly connecting different gradients of arcs, and every two adjacent channels are symmetrical, intersect every other distance and are arranged according to arcs after intersecting. A cooling working medium smoothly flows in the channels, and the friction resistance coefficient is small. The two branch micro fluid passageway bodies of each micro fluid passageway are staggered, the redevelopment of the hot boundary layer on the front edge of each channel is caused, the thickness of the boundary layers is reduced, the fluid can be in the developing state all the time through the regenerated entrance effect, and the heat dissipation performance of heat dissipation devices is improved.

An electrical communications element having a foamed plastic insultation extruded about a conductor with said insulation including at least one component with more than 20% by weight of an ultra-high die swell ratio polymer (UHDSRP), preferably around 15% by weight. The UHDSRP is defined as greater than 55% die swell ratio and more preferably greater than 65% die swell ratio. The insulation also preferably includes at least a second component with a high degree of stress crack resistance, such that the combination of (minimally) these polymers will yield an insulation layer that has a unique combination of physical propeties yielding a high degree of foaming, small uniform cell structure, characteristically lower attenuation, and stress crack resistance capable of withstanding greater than 100 hours at 100° C. while coiled at a stress level of 1 times the insulation outside diameter without failure (cracking).

The invention belongs to the polyester spinning field and relates to an 8-shaped hollow polyester fiber FDY (Fully Drawn Yarn) and a preparation method thereof. A spinning melt contains saturated fatty acid metal salt and modified polyester, wherein the mass ratio of saturated fatty acid metal salt to modified polyester is (0.0005-0.002) to 1; saturated fatty acid metal salt is fatty acid metal salt, the carbon atomic number is 12-22, the melting point is 100-180 DEG C, and the kinetic viscosity is less than or equal to 1Pa.s; a molecular chain of modified polyester comprises a terephthalic acid chain segment, a glycol chain segment and a rigid structure chain segment, and the molar ratio of the rigid structure chain segment to the terephthalic acid chain segment is (0.02-0.05) to 1; and the die swell ratio of the spinning melt is 1.23-1.33, and the after-filtration pressure during the spinning is 85-125kg/cm<2>. The prepared 8-shaped hollow polyester fiber FDY has relatively high degree of hollowness and relatively good shape-preserving effect.

Processes are disclosed for oxygen-tailoring polyethylene blow molding resin. Polyethylene resin is conveyed through a feed zone, a melt-mixing zone and a melt zone, wherein the temperature of the polyethylene resin is from about 216° C. to about 260° C. in the melt zone. The resin is contacted with oxygen in an amount of at least about 20 parts by weight oxygen per million parts by weight resin. The oxygen-treated resin can be used to make polyethylene blow molded articles having improved melt strength, processability, and die swell.

The present invention discloses a system for analyzing and simulating the die swell and the flow profile in polymer melt extrusion through a die, said system typically comprising a mesh generator adapted to generate a computational mesh; a pre-processor adapted to obtain die parameters, boundary conditions, polymer melt parameters including rheological characterization and constitutive equations and to generate an input file; a simulator adapted to receive the input file from the pre-processor and process the input data to simulate die swell; a mesh corrector means adapted to analyze the die swell obtained from said simulator and to correct the motion of the computational mesh and polymer melt to converge the die swell; a post-processor means adapted to visualize the die swell and flow profiles for the polymer melt; and a database means adapted to store the die swell corresponding to the die, mesh and polymer melt parameters.

The invention discloses a composite metal plastic pipe extrusion molding device and a molding method thereof. The device comprises a sieve mesh cover, a connection flange, a wedging ring, a core rod, a material cover, an airless assisted mold and a connecting outer cover; the right end of the airless assisted mold is connected with an air assisted mold; the outer side of the air assisted mold is provided with an air assisted mold outer cover; the air assisted mold outer cover is connected with a mold air inlet cover plate; the leak tightness of air passage is guaranteed through a sealing ring; the right end of the core rod is connected with the inner cover of the core rod; and the right end is connected with the air inlet cover plate of the core rod. The method comprises that lubrication gas with certain pressure is divided into two paths while entering the air assisted molding passage. Since stable air cushion films are formed between the mold, the core rod and the plastic melt, thereby reducing the extrusion pressure, saving the energy consumption, basically eliminating die swelling, improving precision of products, reducing material waste, shortening molding period, and saving the cost.

The invention relates to a principle and a method for improving the stability of a polypropylene melt. The method and the principle are characterized in that: by adding a tetrafluoroethylene polymer with a polypropylene melt strength enhancing function and a flaky component with a melt die swell control function, the melt die swell phenomenon is significantly reduced, and the obtained polypropylene modified material is suitable for thermal forming of various large parts, thus meeting the requirements for extrusion of hollow plates and large-diameter pipes. During extrusion blow molding of large hollow products, the melt dimensional stability can also be ensured. The method and the principle also have the advantages of enhancing the processing speed and reducing the cost.

A flexible flat cable includes an insulating layer disposed through extrusion in vicinity of a plurality of conductors arrayed in parallel with each other. The insulating layer is composed of a vinyl chloride-based resin composition having a die swell ratio of 1.1 or more at a molding temperature during the extrusion. The molding temperature is between 150° C. to 200° C. with a linear rate of between 50 m/minute to 200 m/minute. A melt tension of the vinyl chloride-based resin composition is 0.02 N to 0.2 N.

The invention relates to a flat polyester fiber FDY (Fully Drawn Yarn) and a preparation method thereof. The spinning melt comprises a saturated fatty acid metal salt and polyester, wherein a mass ratio of the saturated fatty acid metal salt to polyester is (0.0005-0.002):1; the filtered pressure during spinning is 84-126kg/cm<2>; a die-swell ratio of the spinning melt is 1.22-1.34; and the saturated fatty acid metal salt refers to a fatty acid metal salt with the carbon atom number of 12-22, the melting point of 100-180 DEG C and the dynamic viscosity of less than or equal to 1Pa.s. The saturated fatty acid metal salt is added into the spinning melt, and the filtered pressure and extrudate swelling during spinning can be effectively reduced, so that the product has an excellent shape preserving effect; meanwhile, the saturated fatty acid metal salt can serve as a nucleating agent, so that the fiber curing speed is increased, and the fiber shape preserving effect is improved. In addition, the fiber structure regularity is not greatly damaged by the saturated fatty acid metal salt, and excellent performances of the polyester fibers are maintained.

This invention presents a Pitot tube design and methodology for determining the flow characteristics of fluids in subsonic and supersonic flow, including the effects of viscosity and turbulence. A new methodology, the Two-Fluid Theory, is developed which treats a real fluid as being composed of two ideal fluids: an inviscid fluid and a Poiseuille fluid. The resulting expression for flow velocity is applicable to a real fluid of any viscosity and to pipes of any L/D ratios, including entrance effects.

Two designs, comprising annular, smooth-bore tubes, with devices for measuring total and static pressures, are presented: one for incompressible flow; one for compressible, supersonic flow. Allowance is made for the viscous component of the flow to become fully developed, in accordance with the Theory.

The invention discloses a device used for preparing high-density powder metallurgy parts, and belongs to the technical field of powder metallurgy. The device comprises an impact unit (1), a side plate (2), a base (3), a die frame (4), a hydraulic system (5), a die wall lubricating device (6), a die wall lubricating system (7) and a control system (8). The device has the advantages that the combination of a high-speed pressing device and an electrostatic die wall lubricating device realizes the preparation of the high-density powder metallurgy parts (the density is higher than 7.4 g/cm) by carrying out automatic die wall lubrication during high-speed pressing without adding a lubricating agent into the powder, the product precision is ensured, the product shrinkage is reduced, the environment pollution is reduced, and the production cost of the powder metallurgy parts is reduced. Simultaneously, the operation and matching of steps of the device are controlled by a programmable logic controller (PLC), and the automatic production can be realized.