摘要:
An injection-molding die including: a fixed die; a movable die; a cavity defined by the fixed die and the movable die; and a gate for injecting a melt resin into the cavity. The cavity includes: a flow-dividing structure that divides a flow of the melt resin injected into the cavity into a plurality of resin flows; and a flow-advancing area in which the resin flows generated by the flow-dividing structure are merged together. The flow-advancing area is formed thicker than a flow-hesitating area of the flow-advancing area in the cavity.
摘要:
After introducing gas into a cavity of a clamped die to boost a pressure therein, a resin material containing a foaming agent is injected. After forming a skin layer, at the same time as a start of a core-back operation for foaming the resin material or after the core-back operation, gas in the cavity is vacuum-suctioned to make a pressure in the cavity less than the atmospheric pressure. By cooling and solidifying, an injection foam molded article is obtained. Before complete solidification, gas between the resin material and an inner surface of the die is reliably discharged out of the cavity, so that surface recesses and generation of swirl marks due to gas accumulation can be prevented.
摘要:
[Object] To provide a polypropylene resin composition for use in the formation of a microporous membrane having excellent heat resistance and low thermal shrinkage ratio.[Solution] A polypropylene resin composition for use in the formation of a microporous membrane according to the present invention comprises as an essential component a propylene homopolymer (A) that satisfies the following requirements (1) to (4) and (7): (1) the intrinsic viscosity [η] is 1 dl/g or more and less than 7 dl/g; (2) the mesopentad fraction ranges from 94.0% to 99.5%; (3) the integral elution volume during heating to 100° C. is 10% or less; (4) the melting point ranges from 153° C. to 167° C.; and (7) in an elution temperature-elution volume curve, the maximum peak has a peak top temperature in the range of 105° C. to 130° C. and a half-width of 7.0° C. or less.
摘要:
An object of the invention is to provide foaming polypropylene resin compositions that are suited for injection foam molding, have excellent balance between flowability and melt tension, are foamable at high expansion ratio, and can give lightweight molded foams having excellent appearance and mechanical strength. Another object is to provide injection-molded foams using the compositions.A foaming polypropylene resin composition of the invention includes: 50 to 90 parts by weight of a high-molecular weight component-containing impact polypropylene (AB); 10 to 30 parts by weight of a rubber component (C); and 0 to 20 parts by weight of an inorganic filler (D) (wherein the total of (AB), (C) and (D) is 100 parts by weight); and the high-molecular weight component-containing impact polypropylene (AB) contains 4.5 to 31.0 wt % of a propylene/ethylene copolymer that is identified as a normal temperature paraxylene soluble component, and the high-molecular weight component-containing impact polypropylene (AB) contains 0.2 to 3.7 wt % of a propylene polymer component having an intrinsic viscosity [η] at 135° C. in tetralin of 13.5 to 20.0 dl/g.
摘要:
The extruded propylene-based resin composite foam (1) according to the present invention is provided by extrusion-foaming a molding material containing a propylene-based resin. The propylene-based resin forming the extruded foam has an olefin-based polymer whose loss tangent (tan δ) is 0.04 to 100 at a temperature of 298 K and a frequency of 10 Hz. The molding material includes a fibrous filler in an amount of more than 0 mass % and 60 mass % or less of the entirety of the molding material. The extruded composite foam (1) includes: first extruded foam (2) whose closed cell content is 40 percent or more and whose expansion ratio is 10 or more; and second extruded foam (3) whose closed cell content is less than 40 percent and whose expansion ratio is 10 or more.
摘要:
Main object is to provide a composition for parts of the intake system, which is capable of enhancing the flexural elasticity modulus of the parts of the intake system and reducing the specific gravity of the parts. Disclosed is a fiber reinforced resin composition for parts of intake system on the internal combustion engine comprising a block polypropylene type resin which has a MFR in the range of 40-70 g/10 minutes (at 230° C. and under a load of 2.16 kg) and which is in the range of 60-80% by weight of the composition, and glass fibers and mica the total of which are in the range of 20-40% by weight of the composition.
摘要:
It is an object of the present invention to provide a polypropylene resin for syringe that can be used as a raw material for syringe that is excellent in sanitary property, heat resistance and transparency and hardly elutes low molecular weight substance and that can prevent formation of foam during molding, achieve long-run moldability and being prevented from scratches when removed from a core molding die in injection molding at satisfactory levels that have not been achieved conventionally. The polypropylene resin for syringe of the present invention comprises an ethylene-propylene block copolymer (A) having a melt flow rate (ASTM D 1238, 230° C., 2.16 kg load) of 10 to 60 g/10 min and being constituted of 85 to 97% by weight of a room-temperature n-decane-insoluble portion (Dinsol) and 3 to 15% by weight of a room-temperature n-decane-soluble portion (Dsol) (the total amount of the Dinsol and the Dsol is 100% by weight), wherein the Dinsol and the Dsol satisfy specific requirements.
摘要:
An injection-molding die including: a fixed die; a movable die; a cavity defined by the fixed die and the movable die; and a gate for injecting a melt resin into the cavity. The cavity includes: a flow-dividing structure that divides a flow of the melt resin injected into the cavity into a plurality of resin flows; and a flow-advancing area in which the resin flows generated by the flow-dividing structure are merged together. The flow-advancing area is formed thicker than a flow-hesitating area of the flow-advancing area in the cavity.
摘要:
A novel propylene resin composition which can readily impart polypropylene fibers with excellent dyeability and can provide dyed fibers improved in washing resistance and weatherability is provided. A polypropylene resin composition obtained by melt blending the following components (A) to (C): (A) 85 to 95 mass % of a polypropylene-based resin; (B) 3 to 9 mass % of ethylene vinyl acetate (EVA); and (C) 2 to 6 mass % of a polyether ester amide-based compound; wherein the vinyl acetate content of the ethylene vinyl acetate as the component (B) is 20 mass % or more and 40 mass % or less, and the melt flow rate of the ethylene vinyl acetate is 10 g/10 min or more and 40 g/10 min or less.
摘要:
Provided is an ethylene polymer of the present invention, which is a copolymer of ethylene and an α-olefin having 4 to 10 carbon atoms, and satisfies the following conditions [1] to [4] simultaneously: [1] an MFR is in the range of 0.10 to 100 g/10 min, [2] a density (D) is in the range of 860 to 930 kg/m3, [3] a ratio (Mw/Mn) of the weight average molecular weight to the number average molecular weight is in the range of 1.50 or more and 3.00 or less, and [4] it satisfies a specific relationship, in accordance with the MFR value of the condition [1], between the ratio (H/W) of the height (H) of a peak having a highest peak intensity to the width (W) at a half of the height of the peak having the highest peak intensity for an elution curve obtained by a temperature rising elution fractionation, and the density (D). The molded products of the invention including the ethylene polymers of the invention have excellent anti-blocking property and low temperature heat sealing property, as well as excellent mechanical strength and thus are suitably applicable to a film and the like.