318 results about "Melt flow index" patented technology

The invention discloses a cross-linking type biodegradable POF heat shrink film and a preparation method thereof, and belongs to the technical field of heat shrink films, and the cross-linking type biodegradable POF heat shrink film is characterized by comprising three layers of films which are sequentially attached, each of the first-layer film and the third-layer film comprises the following raw materials in percentage by weight: 89.5-94% of PP, 2-6% of degradable master batch, 0.5-3% of an anti-blocking agent and 1-4% of a slipping agent; the second-layer film is prepared from the following raw materials in percentage by weight: 30 to 35 percent of LLDPE-A, 9 to 14.5 percent of toughening agent, 0.5 to 1 percent of degradable master batch, 40 to 45 percent of LLDPE-B and 10 to 15 percent of metallocene LLDPE; the melt index of the LLDPE-A is 2.5 g / 10min, the melt index of the LLDPE-B is 2.1 g / 10min, the melt index of the metallocene LLDPE is 1.0 g / 10min, and through the synergistic effect between the LLDPE with different melt indexes and the flexibilizer, the low-temperature tear resistance of the heat shrink film is effectively improved.

The invention relates to the technical field of material performance detection, in particular to a rapid testing method for thermal aging failure of an oil and gas pipeline anticorrosive coating material, which comprises the following steps: testing oxidation induction time t of a sample; respectively carrying out thermal aging with different time lengths at 150 DEG C, measuring and calculating A (tri) / A (on) and a melt index change rate, establishing a linear equation of the A (tri) / A (on), and calculating A '(tri) / A' (on) corresponding to 35% of the melt index change rate; carrying out thermo-oxidative aging on the sample at different time lengths, measuring and calculating A (tri) / A (on), and obtaining aging time t'according to A '(tri) / A' (on); carrying out oxidation induction time test on the thermally aged material to obtain a rate coefficient k; and calculating the aging time corresponding to the material failure critical point. The test method provided by the invention can rapidly characterize the thermal aging failure critical point of the anticorrosive coating material, and provides a scientific basis for development of the material.

The invention provides a modified engineering plastic melt index real-time monitoring method which comprises the following steps: determining a melt index difference value of adjacent monitoring points by acquiring a melt index value of each section of an extrusion production line; obtaining the number of shearing cycles of the extrusion production line, identifying the fiber shearing damage degree of each section according to the melt index difference and the number of shearing cycles to obtain fiber damage distribution, and determining the fiber fracture position according to the fiber damage distribution; the melt index difference value corresponding to the fiber fracture position is analyzed by obtaining the melt index of the fiber fracture position, and the monitoring point interval is dynamically adjusted through the melt index difference value; and obtaining the melt index value and the fiber shortening amplitude after the interval adjustment of the monitoring points, and comparing the melt index change and the fiber length loss of each monitoring point to obtain the corresponding distribution of the fiber shortening amplitude and the melt index value.

The invention relates to the technical field of polymer compositions, and discloses a fiber microcrack self-healing composition with a shape memory characteristic, which comprises modified polyester containing thermally reversible dynamic covalent bonds and an asymmetric polyether-polyester block copolymer interface regulator, the melt index ratio of the interface regulating agent to the modified polyester is 1.8-3.2, and the interface regulating agent is distributed on the periphery of the modified polyester to form a core-shell microdomain. By utilizing the rheological gradient among the components, the interface regulating agent forms a low-viscosity flowing layer when the matrix shrinks; and the modified polyester is restrained to directionally migrate towards the tip of the fiber microcrack, so that active closing and densification filling of the crack area are realized, micro holes in the repaired area are eliminated, and the mechanical continuity of the composition in a dynamic environment is kept.

The invention discloses an accurate temperature control method and system for regeneration and recovery of injection molding products, and relates to the field of temperature control. The method comprises the following steps: analyzing regenerated plastic components in real time through a near-infrared spectrometer, and obtaining a melt index, a thermal stability parameter and a glass transition temperature; establishing a melt apparent viscosity-temperature-shear rate three-dimensional response curved surface model in combination with a rheology theory; the method comprises the following steps: acquiring temperature gradient and pressure data by utilizing a multi-sensor network deployed in each module of a double-screw extruder, calculating an actual shear rate and melt apparent viscosity, and comparing the actual shear rate and melt apparent viscosity with theoretical values to trigger a PID (Proportion Integration Differentiation) neural network to predict temperature fluctuation so as to carry out differential temperature compensation on a feeding section and a melting section; and after each batch of production, model parameters are optimized by adopting a least square method, so that closed-loop intelligent regulation and control in the processing process of the regenerated plastic are realized. The method has the advantages that through the three-dimensional model, the PID neural network differential temperature control is combined, the temperature control problem of the regenerated plastic is solved, the quality stability of products is improved, and the waste rate is reduced.

The present invention relates to oriented, multilayer polyethylene films. In one aspect, a biaxially oriented, multilayer polyethylene film comprises: at least one inner layer comprising: (1) a polyethylene-based composition that comprises: (a) at least 97% by weight, based on the total weight of the polyethylene-based composition, of one or more polyethylenes having a density between 0.926 g / cm3 to 0.970 g / cm3 and a melt index (I2) between 0.1 to 10 g / 10 min; (b) 20 to 5000 ppm, based on the total weight of the polyethylene-based composition of a sorbitol acetal derivative comprising the structure of formula (I): wherein R1-R5 comprise the same or different moieties chosen from hydrogen and a C1-C3 alkyl.

The present invention relates to a polyolefin polymer, and a system and method for polymerizing same, the polymer having a density of 0.868 to 0.897 g / cm3, a melt flow index (MIE, 190°C with a load of 2.16 kg) of 0.1 g / 10 min to 20.0 g / 10 min, a PDI of 1 to 5, a number average molecular weight (Mn) of 20,000 to 70,000 g / mol, a weight average molecular weight (Mw) of 50,000 to 150,000 g / mol, and two or more melting temperatures (Tm).

The invention relates to the technical field of high polymer materials, in particular to a polyethylene flame-retardant master batch and a production process thereof. The polyethylene flame-retardant master batch is prepared from the following raw materials in parts by weight: 50 to 60 parts of polyethylene, 10 to 20 parts of hydroxymethyl phosphinic acid, 15 to 20 parts of HDPE-g-MAH, 0.8 to 1.5 parts of an initiator, 1 to 2 parts of an antioxidant and 3 to 6 parts of functional particles. The polyethylene is selected from high-density polyethylene, and the melt index of the polyethylene is 7-20g / 10min under the conditions of 190 DEG C and 2.16 kg; the polyethylene flame-retardant master batch produced by the invention not only can effectively enhance the flame retardant property of a polyethylene product, but also can effectively improve the anti-aging property of the polyethylene product; and the service life of the polyethylene product is prolonged to a certain extent while the quality of the polyethylene product is ensured.

Disclosed herein is a blown film comprising at least 50 wt.% of a polyethylene composition comprising the reaction product of ethylene and optionally, one or more alpha-olefin comonomers, wherein the polyethylene composition is characterized by the following properties: a melt index, I2, of from 0.1 to 2 g / 10 min; a density of from 0.940 to 0.970 g / cm³; a melt flow ratio, I10 / I2, of from 5.5 to 7.2; and a molecular weight distribution (Mw / Mn) of from 2.2 to 3.5.

The invention relates to a polypropylene material as well as a preparation method and application thereof. The polypropylene material comprises the following components: co-polypropylene, the co-polypropylene comprises a continuous phase formed by a homo-polypropylene chain segment and a rubber phase formed by an ethylene-propylene copolymer chain segment; the isotacticity of the homo-polypropylene chain segment is 98 to 99 percent; the mass percentage content of the rubber phase in the co-polypropylene is 10-15%; the mass percentage content of the ethylene unit in the rubber phase is 20-40%; the melt index of the polypropylene material is 60 to 100g / 10min. Through component design, the polypropylene material provided by the invention has the characteristics of high melt index, high modulus and high impact resistance, and can meet the application requirements of large thin-wall workpieces.

The utility model discloses a melt index tester which comprises a tester main body, the outer wall of a charging barrel is in sliding sleeve connection with the tester main body, a heating coil for heating the charging barrel is arranged in the tester main body, the bottom of the charging barrel is connected with a mold outlet, a piston assembly is arranged in the charging barrel, and the piston assembly is arranged in the charging barrel. The piston assembly is used for extruding molten materials in the charging barrel to be discharged, the fixed lantern ring fixedly sleeves the top of the outer wall of the charging barrel, the fixed lantern ring is slidably clamped to the top of the tester main body, and the handle assembly is arranged on the side of the fixed lantern ring. According to the utility model, the tester main body, the charging barrel, the fixed lantern ring, the piston assembly and the handle assembly are matched for use, under the action of the handle, the limiting block and the locking rod, the stability of the connecting plate and the fixed lantern ring mounted on the tester main body can be ensured, the locking rod is driven by the handle to be separated from the limiting block, and the charging barrel can be directly taken out; and therefore, the charging barrel is detached and cleaned.

This invention relates to the field of polymer materials technology, specifically disclosing the application of low melt flow index (MFI) polyoxymethylene (POM) in improving the spinning performance of POM. Using heteropolyacids as catalysts, and controlling the polymerization temperature and the amount of heteropolyacid catalyst added, low MFI POM with a melt flow index of 0.1 g / 10 min to 2.5 g / 10 min was prepared. After compounding this low MFI POM with a heat-stabilizing agent in a certain proportion, it was blended with general-purpose POM and extruded into granules. Unexpectedly, the thermal stability of the POM was significantly improved, and it also exhibited moderate rheological properties. When applied to the melt spinning process, the spinnability of the POM was significantly improved. Compared with the POM without the addition of this low MFI, the draw ratio increased by approximately 1.4 times, and the tensile strength of the POM fiber reached 6–8 g / d, a maximum increase of approximately 1.4 times. The yield and strength of the finished fiber product were significantly improved.

The present disclosure relates to a polymer blend (I) comprising: A) a first polyethylene component in a wt.% A amount from 5 to 80 wt.%, having a density DA from 0.926 to 0.945 g / cm3, a Melt Index MIE from 0.1 to 3 g / 10 min and Mw / Mn of 7 or greater; B) a second polyethylene component in a wt.% B amount from 5 to 80 wt.%, having a density DB from 0.949 to 0.965 g / cm3, a Melt Index MIF from 5 to 28 g / 10 min. and a ratio MIF / MIP from 5 to 10.5; C) a third polyethylene component in a wt.% C amount from 10 to 40 wt.%, having a density DC from 0.949 to 0.965 g / cm3, a Melt Index MIF from 10 to 40 g / 10 min. and a ratio MIF / MIP from 11 to 30; wherein the wt.% A of the first polyethylene component A), the wt.% B of second polyethylene component B) and the wt.% C of third polyethylene component C) are with respect to the overall weight of A) + B) + C).

This invention discloses a thermoplastic elastomer composition, its preparation method, and its applications. The thermoplastic elastomer composition of this invention comprises the following components: PP resin I, SEBS, TPV, glass fiber powder, paraffin oil, antioxidant, and light stabilizer; wherein, the PP resin I conforms to ISO 1133-1-2011 standard, with a melt index of 80–130 g / 10 min at 230°C and 2.16 kg; the SEBS has a weight-average molecular weight of 80,000–160,000; and the TPV comprises PP resin II and EPDM. The thermoplastic elastomer composition of this invention combines PP resin with a specific melt index, SEBS with a specific weight-average molecular weight, and TPV, resulting in a thermoplastic elastomer composition that possesses both high fluidity and low gloss, as well as excellent high-temperature resistance.

A multilayer film suitable for manufacturing a stretch hood used to secure palletized goods during shipment and transport. The multilayer film comprises at least three layers and includes a first layer comprising a linear low density polyethylene resin having a melt index within the range of 0.20 and 0.60 dg / min and a density within the range of 0.910 to 0.914 g / cm3, a second layer comprising a linear low density polyethylene resin having a melt index within the range of 0.20 and 0.60 dg / min and a density within the range of 0.910 to 0.914 g / cm3, and at least one intermediate layer in between the first and second layers, the intermediate layer or layers including a linear low density polyethylene resin having a fractional melt index and a thermoplastic polyolefin having a melt index within the range of 0.30 and 0.70 dg / 10 min and a density within the range of 0.870 to 0.890 g / cm. The multilayer film having a total thickness between 4.85 and 6.7 mils and a density between 0.909 and 0.913 g / cm3. A stretch hood fabricated from such multilayer film exhibits exceptionally high holding force and, provides robust stability when utilized on palletized goods during transport. A method of manufacture of such multilayer film is also provided.

The application belongs to the technical field of precision casting, and particularly relates to a high-viscosity and high-strength precision casting adhesive wax and a preparation method thereof. The adhesive wax comprises the following components: 30-40 parts of paraffin wax, 16-24 parts of microcrystalline wax, 25-30 parts of petroleum resin, 8-14 parts of rosin resin, 5-10 parts of EVA, 2-5 parts of LDPE and 0.1-2 parts of additives; wherein the LDPE is composed of two kinds of LDPE with different melt indexes. By introducing the petroleum resin, rosin resin, ethylene-vinyl acetate copolymer (EVA) and low-density polyethylene (LDPE) into the paraffin wax and microcrystalline wax base system, and controlling the proportion between the resin system and the polyolefin reinforcing system, the adhesive wax has high viscosity and hardness at 100 DEG C, and the bending strength is improved. Thus, the comprehensive performance of the adhesive wax is achieved, i.e., the adhesive wax is not easy to sag at high temperature, is not easy to be pressed at room temperature, and is not easy to crack under stress.

The invention provides an antistatic polyether-ether-ketone composition and application thereof. The composition comprises first polyether-ether-ketone resin (the melt index is 8-15 g / 10 min), second polyether-ether-ketone resin (the melt index is 60-80 g / 10 min), a composite antistatic agent and a rare earth nucleating agent. The polyetheretherketone resin with a low melt index is used as a substrate material, and the polyetheretherketone resin with a relatively high melt index is additionally added, so that the flowability of a composition system can be regulated and controlled, the processing is convenient, and a product with a smooth surface can be obtained. Meanwhile, the composite antistatic agent is added, the antistatic function is achieved, and the antistatic performance is stable after extrusion molding. Furthermore, the rare earth nucleating agent is added, so that crystallization of the subsequently prepared polyether-ether-ketone pipe can be promoted, the polyether-ether-ketone pipe with high bursting strength can be obtained without a post-treatment process, meanwhile, excellent mechanical properties are kept, and the polyether-ether-ketone pipe is easy to process and form.

Disclosed herein are multimodal polyethylene compositions, and pipes including the same. The compositions include a first component and a second component, where the composition according to embodiments disclosed herein can have a density from 0.940 g / cm3 to 0.955 g / cm3; a melt index (I2) of at least 0.20 g / 10 min; and a Tp MW of greater than 150,000 g / mol at an elution temperature range of 90.0°C to 95.0°C. Pipes made from the compositions can have an improved balance of properties.

The present disclosure relates to polyethylene copolymers. The polyethylene copolymers include 90 wt% or greater ethylene units and a remainder balance of C3-C20 comonomer units. The polyethylene copolymers have a melt index of about 0.1 g / 10min to about 2.2 g / min, a high load melt index (HLMI) of about 10 g / 10 min to about 50 g / 10 min, a melt index ratio (MIR) of about 20 to about 35, a molecular weight distribution (MWD) of about 3 to about 7, a melt strength of about 0.03 N to about 0.10 N, a ∆CWF / ∆T of about wt% / 0.02 °C to about 0.03 wt% / °C, a SignCDI *ɳ0*1032 / (Tan delta (ω=0.1) * MW6.82) of about 2 Pa*s / [(g / mol)6.82]to about 8 Pa*s / [(g / mol)6.82], and a CDI_NWZ,w of about 0.200 to about 0.33.

The present application relates to the field of resins, discloses an ethylene-vinyl alcohol copolymer and a preparation method, application and film thereof. The copolymer has a melt index of MFR 21.6 at 190 DEG C and a load of 21.6 kg, a melt index of MFR5 of the copolymer at 190 DEG C and a load of 5 kg, a melt index of MFR 2.16 of the copolymer at 190 DEG C and a load of 2.16 kg, and the MFR 21.6 , MFR5 and MFR 2.16 satisfy the following relationship: 10 ≤ MFR 21.6 / MFR 2.16 -MFR5 / MFR 2.16 ≤ 25. The ethylene-vinyl alcohol copolymer provided by the present application has good processing stability, long processing operation cycle, less surface defect number and small crystal point defect.

Disclosed are a sphere-like super-macroporous mesoporous material, a polyolefin catalyst, and a preparation method therefor and an olefin polymerization process. The sphere-like super-macroporous mesoporous material has a two-dimensional hexagonal ordered pore channel structure. The mesoporous material has an average pore size of 10 nm to 15 nm, a specific surface area of 300 m2 / g to 400 m2 / g, and an average particle size of 1 μm to 3 μm, based on the total mass of the mesoporous material. The mass content of water in the mesoporous material is <1 ppm. The mass content of oxygen in the mesoporous material is <1 ppm. When a polyolefin catalyst prepared with the mesoporous material as a carrier is used for an olefin polymerization reaction, a polyolefin product with a narrow molecular weight distribution and a good melt index can be obtained.

Disclosed herein are multimodal polyethylene compositions, processes for making the same, and pipes made from the same. The multimodal polyethylene composition includes a first component and a second component. The composition according to embodiments disclosed herein has a density from 0.940 g / cm3 to 0.955 g / cm3; a melt index (I2) of at least 0.30 g / 10 min; and a Tp MW of greater than 145,000 g / mol at an elution temperature range of 90.0°C to 95.0°C. Pipes made from the composition can have a desirable balance of properties, including slow growth crack and hydrostatic pressure properties.

The invention relates to a composition comprising at least one thermoplastic polyamide, wherein the average carbon content of the repeating units of said at least one thermoplastic polyamide is greater than or equal to 7; from 0.1 to 6.0 % by weight of expandable microspheres, based on the total weight of the composition; and optionally at least one additional thermoplastic polymer; wherein the composition has a melt flow index lower than or equal to 150 g / 10 min. The invention also relates to a method for preparing such a composition, to an expanded composition obtainable from such a composition and to a method for producing said expanded composition.

The object of this invention is to provide a composition for sintered molding bodies that does not impair the shape retention of the rigid green body based on polyacetal resin, has high fluidity, and does not crack or bulge during degreasing. The composition for sintered molding bodies of this invention is characterized in that it comprises a sinterable inorganic powder and an organic binder, wherein the organic binder comprises at least a polyacetal resin and a polyolefin resin, and the melt flow index of the polyacetal resin is 70 g / 10 min to 200 g / 10 min.

The application provides a preparation method of a self-assembled multilayer co-extrusion high-water-resistance high-toughness PE film, which comprises the following steps: using ultrahigh-viscosity polyethylene resin material as a surface layer, arranging a core layer in an alternating manner of low-viscosity polyethylene resin material and ultrahigh-viscosity polyethylene resin material, and co-assembling the surface layer and the core layer into a multilayer resin layer with an odd number of layers; using a multilayer co-extrusion technology to co-extrude the multilayer resin layer into a film to obtain the self-assembled multilayer co-extrusion high-water-resistance high-toughness PE film; the ultrahigh-viscosity polyethylene resin material has a melt index of less than 0.1 g / 10 min under a test condition of 21.6 KG / 190 DEG C; and the low-viscosity polyethylene resin material has a melt index of 0.5-2.0 g / 10 min under a test condition of 2.16 KG / 190 DEG C. By compounding the ultrahigh-viscosity polyethylene resin with other different types of polyethylene resin materials, designing a special hierarchical structure, utilizing the stress difference of the materials with different viscosities under the same mold to generate secondary flow, and self-assembling a petal-shaped or leaf-shaped interlayer structure, the barrier property of the film product is significantly improved, and the film has the characteristics of high toughness.

The invention discloses a preparation method of low-viscosity polyether-ether-ketone, which belongs to the technical field of polymer synthesis, and is characterized by comprising the following steps: under inert atmosphere and high-temperature conditions, carrying out polycondensation reaction on a difluoro monomer and a bisphenol monomer in the presence of alkali carbonate, and before the polycondensation reaction is finished, carrying out condensation polymerization on the difluoro monomer and the bisphenol monomer to obtain the low-viscosity polyether-ether-ketone. Adding a compound containing a p-methylphenyl group as a fluidity modifier to prepare low-viscosity polyether-ether-ketone; according to the invention, the specific p-methylphenyl group-containing compound is introduced into the polymerization reaction, so that the viscosity at a high shear rate is greatly improved on the premise of not sacrificing the melt index of the material, and the processing fluidity is improved.

Embodiments of the present disclosure generally relate to polyethylene copolymer resins and methods thereof. In some embodiments, a polymer includes a polyethylene copolymer having ethylene units and comonomer units. The polyethylene copolymer includes a density of about 0.907 g / cm3 to about 0.913 g / cm3, wherein the density of the polyethylene copolymer is determined in accordance to ASTM D1505. The polyethylene copolymer further includes a melt index (I2) of about 4 g / 10 mm to about 8 g / 10 mm, wherein the I2 is determined in accordance to ASTM DI 238. The polyethylene copolymer further includes an olefin comonomer content of about 12.5 wt% to about 15 wt%.

High-density polyethylene according to the present invention can improve both processability and excellent moisture barrier properties, without degradation of physical properties during film processing and without blending with low-density polyethylene or the like, through fine control of a melt flow index, a polydispersity index (PDI), and elongation viscosity, in addition to having a high density.

The invention provides a catalyst component for olefin polymerization, a catalyst, application of the catalyst and an olefin polymerization method, and the catalyst component comprises magnesium, titanium, halogen and an internal electron donor compound, the internal electron donor compounds comprise a first internal electron donor compound as shown in a general formula (I) and a second internal electron donor compound as shown in a general formula (II); the molar ratio of the first internal electron donor compound to the second internal electron donor compound is 1: (0.01-100); when the catalyst component or the catalyst is used for olefin polymerization reaction, the catalytic activity is high, the hydrogen regulation sensitivity is good, and the obtained olefin polymer is high in melt index, wide in molecular weight distribution and high in isotactic index.

The application discloses a kind of wide distribution easy processing polyethylene and its application.The weight average molecular weight of the wide distribution easy processing polyethylene is 10×10 4 -45×10 4 G / mol, molecular weight distribution is 35-50, the component content of molecular weight ≥100×10 4 G / mol is 1-10wt%, the component content of molecular weight ≤1000g / mol is 0.5-2.5wt%, density is 0.940-0.960g / cm 3 , melt index is 8-15g / 10min, branched chain content ≤0.2C / 1000C, breaking tensile strength ≥50MPa.The matt material consisting of wide distribution easy processing polyethylene and polypropylene is applied to multilayer co-extrusion casting film, with the characteristics of high haze, small haze deviation, high water vapor barrier performance.