Patent classifications
B29B7/482
THERMOPLASTIC RESIN COMPOSITION HAVING EXCELLENT HEAT RESISTANCE AND ELECTROMAGNETIC WAVE SHIELDING CAPACITY, METHOD OF PREPARING THERMOPLASTIC RESIN COMPOSITION, AND INJECTION-MOLDED ARTICLE MANUFACTURED USING THERMOPLASTIC RESIN COMPOSITION
Provided is a thermoplastic resin composition, including (a) 100 parts by weight of a thermoplastic resin including 80-100% by weight of a base resin and 0-20% by weight of a reinforcing resin; (b) 2-60 parts by weight of linear carbon fibers having an average diameter of 1-15 μm; (c) 1-5 parts by weight of carbon nanofibrils having a BET specific surface area of 200-400 m.sup.2/g; (d) 1-15 parts by weight of carbon nanoplates; and (e) 1-25 parts by weight of metal powder, a method of preparing the thermoplastic resin composition, and an injection-molded article manufactured using the thermoplastic resin composition. The thermoplastic resin composition has excellent mechanical properties, e.g., impact strength, and also excellent conductivity, heat resistance, and electromagnetic wave shielding capacity, particularly high shielding efficiency against high-frequency electromagnetic waves, and thus can be used as automobile, electric, and electronic parts, and as a substitute for aluminum alloys and magnesium alloys.
Co-rotating self-cleaning two-screw extruder with a gradual number of threads and through self-cleaning function, and a processing method using the same
A co-rotating self-cleaning two-screw extruder with a gradual number of threads and through self-cleaning function, and a processing method using the same, are disclosed. The screw assembly in the extruder includes a first screw (3) and a second screw (4) that co-rotate at the same speed in engagement; the first screw (3) includes a first single threaded element, a first transition element, a multiple threaded element, a second transition element and a second single threaded element that are connected in sequence; and the second screw (4) includes a first single threaded element, a third transition element, a multiple threaded element, a fourth transition element and a second single threaded element that are connected in sequence. The materials are transferred by rotation of the first (3) and second screws (4), and get their respective compositions mixed based on the structure of a gradual number of threads; with the flow passage expanded, contracted and re-expanded in shape in sequence, the materials undergo the single-to-multiple threaded, multiple-to-single threaded and again single-to-multiple threaded chaotic mixing in sequence; and the first and second screws achieve the self-cleaning effect by wiping each other.
EXTRUSION METHOD FOR PRODUCING A THERMOPLASTIC MOLDING COMPOUND, AND DEVICE FOR CARRYING OUT THE METHOD
Method for producing a thermoplastic molding compound (F) in an extruder, which has at least one screw having an outside diameter (D), wherein a thermoplastic component (TP) containing at least one thermoplastic polymer, a component (C) containing a graft polymer based in particular on butadiene and/or acrylate, and optionally a component (Z) containing additives are heated to a temperature of 200° C. to 280° C., melted and mixed by supplying thermal energy in a melting section (S) and/or in at least one mixing section (M) such that the thermoplastic molding compound (F) is formed, and the thermoplastic molding compound is subsequently degassed in a degassing zone (E) of the extruder, wherein an absolute pressure (P1) of less than 2 bar is set in this zone, and after the degassing the molding compound (F) is conveyed to a melt pump (SP) by screw elements, wherein the total length of the screw elements of a conveying path (FS) from the degassing opening (O) to the melt pump (SP) is less than five times the outside diameter (D) of the at least one screw.
Process and Apparatus for Continuous Granulation of Powder Material
The present disclosure relates to a process for preparing granules from an input material or a powder material. The process comprises feeding the input material for granulation in the processor using one or more powder feeders, introducing steam as a granulation activating agent in the processor, granulating the input material in presence of the steam to form granules, and optionally collecting the granules from a discharge zone of the processor, wherein feed rate of the steam into the processor is determined based on feed rate of the input material into the processor. A co-rotating twin-screw processor for preparing granules is also disclosed.
Continuous twin-screw mixer and mixing method
A continuous mixer includes a barrel with a hollow interior, and a pair of mixing rotors housed in the barrel and that rotate in mutually different directions, each mixing rotor including a mixing portion with plural mixing flights formed about an axial center of the mixing rotor and projecting radially outward. The mixing rotors have a center distance therebetween smaller than a rotation outer diameter of each of the respective mixing flights. An inter-rotor clearance, which is the smallest clearance between the mixing portions at each rotation phase of the mixing rotors in a cross section perpendicular to axial directions of the both mixing rotors, has a dimension allowing an extensional flow to be generated in a material passing through the inter-rotor clearance. The continuous mixer can reliably and efficiently mix a material having a large viscosity difference between a dispersed phase and a matrix phase.
Method and device for continuously modifying a polymer melt made of non-extracted polyamide 6 with one or more additives
A method and a device for admixing additives into a polymer melt made of non-extracted polyamide 6 are disclosed. The polymer melt is combined in a highly concentrated form with an additional melt flow without additives and mixed therewith. Additionally, a part of the melt is branched off from a main melt flow (3), wherein the sub-melt flow (4) is transported into a dispersing device (5) and is supplied and mixed with one or more additives (12). The side-melt flow (4) with additives is then returned into the main melt flow (3), mixed with the main melt flow, and subsequently supplied for further processing.
DEVICE FOR THE SUCCESSIVE INTRODUCTION OF ADDITIVES INTO A POLYMER GRANULATE AND USE OF THE DEVICE
The invention focuses on a device for sequentially introducing additives in a polymer granulate and the use of the device for mixing the polymer granulate with the additives. The device consisting of a mixer with housing, comprising at least one mixer shaft attached in helix arranged non-continuous conveying pattern shapes, being rotated by a drive for the transport, whereby the mixer in the housing featuring an inlet for the polymer granulate to be mixed and each of the several subsequent inlets for the additive is followed by an outlet for the polymer granulate mixed with the additive, so that two or several mixing zones being formed in the mixer and whereby at least between at two mixing zones on the surface of the mixing shaft one section featuring a continuous screw conveyor instead of the non-continuous conveying pattern shapes, the section not being penetrable for returning solids from the subsequent mixing zone.
PROCESS FOR PREPARING FIBER REINFORCED POLYVINYL CHLORIDE COMPOSITION AND PRODUCTS
A process for preparing a fiber reinforced thermoplastic is disclosed. The process includes melting a first thermoplastic and a second thermoplastic in a melting zone of a twin-screw processor, feeding at least one continuous fiber downstream of the melting zone into a melted mixture of the first thermoplastic and the second thermoplastic, incorporating the at least one continuous fiber into the melted mixture in a mixing zone, the mixing zone including at least one wave element having a continuous outer surface in the form of a helical wave, and obtaining the fiber reinforced thermoplastic from the twin screw processor. Further, a fiber reinforced thermoplastic composition prepared by an extrusion process the composition having a density between 1.3 g/cc to 1.7 g/cc and a flexural modulus of at least 4000 MPa is disclosed.
TWIN-SCREW DRY GRANULATION FOR PRODUCING SOLID FORMULATIONS
A dry granulation process using a twin-screw extruder for granulating a powder mixture which includes at least one active ingredient and at least one carrier. The process includes steps of kneading the powder mixture in the screw barrel of the twin-screw extruder at a barrel temperature below a melting point of the at least one active ingredient and a melting point or a glass transition temperature of the at least one carrier to provide a kneaded powder mixture, and extruding the kneaded powder mixture to form granules. Granules and tablets produced using the dry granulation process in the twin-screw extruder are also provided.
METHOD OF PRODUCING POWDER COATING MATERIAL
The present invention relates to a method of producing a powder coating material containing a fluororesin and a non-fluororesin. The method of producing a powder coating material includes kneading a raw material containing the fluororesin and the non-fluororesin with a kneading extruder equipped with a screw having a kneading zone, wherein a ratio of a length L.sub.K of the kneading zone to an effective length L.sub.S of the screw (L.sub.K/L.sub.S100) is 21.0 to 50.0%.