Methods for extrusion of polyolefins (112 ) that control specific energy input to the extruder (102 ) for gel reduction. Disclosed herein is an example method for forming plastic products (120, 208 ) with reduced gels, comprising: melting a polyolefin resin (112 ) in extruder (102 ) to form a melt; adjusting specific energy input in the extruder (102 ) to reduce gels in the melt; and forming the melt into a polyolefin product (120, 208 ). Disclosed herein is also an example method for forming plastic products (120, 20 ) with reduced gels, comprising: melting a polyolefin resin in extruder (102 ) to form a melt; selecting a throttle valve (104 ) position for gel reduction; setting the throttle valve (104 ) at the selected throttle valve (104 ) position to restrict flow of the melt out of the extruder (102 ); and forming the melt into a polyolefin product (120, 208 ).

Methods for extrusion of polyolefins (110) that utilize melt temperature to control molecular weight and also reduce gels. Disclosed herein is an example method for controlling polymer chain scission in an extrusion system (100), comprising: melting a polyolefin resin (110) in extruder (102) at a first melt temperature to form a first melt (112); passing the first melt (112) through a screen pack (106); forming the first melt 112) into a first polyolefin product (116, 118); melting additional polyolefin resin (110) of the same grade in the extruder (102) at a second melt temperature to form a second melt (112), wherein the second melt temperature differs from the first melt temperature by 5° C. or more to control chain scission in the extruder (102); passing the second melt (112) through the screen pack (106); and forming the second melt (112) into a second polyolefin product (116, 118).

Described is a coextrusion head (1) comprising a plurality of infeeds (11, 12, 13, 14, 15) for fluid products, an inner joining space (16, 17), positioned downstream of said infeeds and communicating with them by means of respective delivery ducts (110, 120, 130, 140, 150) so as to allow flows of products to converge there and an outfeed (18) for the final multi-layer product, positioned downstream of the inner joining space (16, 17). In the head (1) there is a central delivery duct (110), provided for receiving a first flow of product and two lateral delivery ducts (120, 130), designed to receive, respectively, a second flow of product and a third flow of product. The head (1) also comprises adjustable narrowing means (31, 32), acting at least in the central delivery duct (110) and designed to vary a respective opening, to allow adjustment of the relative position of the first flow relative to a composite secondary flow defined by the joining of the first, second and third flow in the joining space (16) .

An extruder system for degassing a mixture, comprising a first extruder, a second extruder arranged downstream of the first extruder and a transfer zone formed between these extruders, characterized by a pressure regulating device which can regulate the pressure at the outlet of the first extruder.

An extruder is provided with: a screw rotationally driven about the axis by a first motor; a barrel having a screw hole into which the screw is inserted and a de-airing port configured to discharge air inside the screw hole; a filter configured such that a part thereof faces the de-airing port of the barrel; and a filter-driving mechanism configured to move the filter to shift the part of the filter facing the de-airing port.

Multiple layer interlayers having enhanced optical and acoustic properties are provided, along with methods of making and using the same. Interlayers as described herein may include at least two outer skin layers and an inner core layer, with one of the outer skin layers having a different thickness than the other at one or more locations along the interlayer. The multi-layer interlayer may also exhibit acoustic properties and, in some cases, may have an overall wedged thickness profile. Additionally, in some aspects, interlayers and laminates formed therefrom may also provide reduced infrared energy transmission, without sacrificing acoustic and/or optical performance.

Described is a system for transferring a dose of polymeric material comprising a head for supplying the polymeric material and at least one conveying device, provided with a conveying wall, which is configured for advancing along a path through the supplying head for transferring to the conveying wall a dose obtained from the polymeric material supplied from the supplying head; and wherein the supplying head comprises a duct which is provided with a straight outfeed region extending along an axis which is configured to supply the polymeric material to a supplying outfeed. The outfeed region comprises at least a first zone and a second zone facing each other, the supplying head having at least one variation configuration in which the first zone and the second zone are asymmetrical to disturb a flow of polymeric material in the outfeed region in such a way as to control the supplying direction of the polymeric material, supplied from the supplying outfeed and to transfer to the conveying wall. A method is also proposed for transferring the dose of polymeric material from the supplying head to the conveying device and a method for supplying the dose.

This invention provides a food container which can be manufactured cheaply by using inexpensive general PET resin or further inexpensive PET resin for fiber or recovered PET flakes, and nevertheless, which has a high heat resistance up to 250° C., and the container is obtained by adding a chain extender and a compatibilizer and talc to PET resin, charging the mixture into an extruder 30 having two or more vent holes, degassing under a condition where the PET resin is melted with heating by sucking at a high vacuum of −99.99 kPa or lower from the vent holes 33, 34, thereafter, forming a sheet by extrusion molding, pressure-forming with vacuum the sheet by a thermoforming machine, forming the container by keeping in a mold at 100-220° C. The container has a total of the content of crystal portion represented by the following formula and the content of talc being 25% by weight or more.

A nozzle is provided for controlling the flow of extruded material, such as e.g., rubber material, from an extrusion machine. Movable pins are positioned into the path of material flow through an internal cavity. The pins are arranged across the path of flow upstream of the extrusion die. By moving the pins in and out, the flow of material through the cavity can be controlled at different locations across the width of the path of flow to the die. Manual and automatic controls can be provided for determining the position of the pins and thereby controlling the flow.

The invention relates to a method and to an assembly for recycling plastic materials, comprising the following processing steps: a) reprocessing the raw material, wherein the material, if necessary, is comminuted and brought into a fluid-like form and heated and permanently mixed, while preserving the lumpiness and pourability thereof, and optionally the viscosity thereof is increased and/or it is degassed, softened, dried and/or crystallized; b) melting the reprocessed material, at least so much that filtration is possible; c) filtering the melt in order to remove impurities; d) homogenizing the filtered melt; e) degassing the homogenized melt; and f) discharging and/or subsequently processing the melt, such as by granulation, blown film processing, with said processing steps being carried out consecutively in the order listed.