A poly(oxyalkylene) polymer and a metal salt of a carboxylic acid, sulfonic acid, or alkylsulfate, in combination are useful as a polymer processing additive synergist. Polymer processing additive compositions, homogeneously catalyzed olefin compositions, and other extrudable polymer compositions including a poly(oxyalkylene) polymer and a metal salt of a carboxylic acid, sulfonic acid, or alkylsulfate are disclosed. Methods of reducing melt defects during the extrusion of a thermoplastic polymer, which may be a homogeneously catalyzed polyolefin, are also disclosed.

The present invention relates to a single-stage process for the production of starch blends in a twin-screw extruder or two twin-screw extruders arranged in series, where i) the starch, together with a plasticizer, passes through a wetting section of length 8D to 30D in an extruder or in a wetting section of length 8D to 80D if two extruders are used at temperatures below the gelatinization temperature of the starch, with mixing, where D is defined as the screw diameter of the screw cylinder and the wetting section is defined as starting at that point on the extruder screw at which the starch and the entire or partial quantity of plasticizer encounter one another and ending at that point in the extruder at which the starch is gelatinized and is digested to give thermoplastic starch; ii) in a plastifying section of length 10D to 50D the extruder temperature is adjusted stepwise to above 130° C., where the starch is digested, destructured and thermoplastified, and is dispersed in a starch-immiscible polymer, and a water content below 5%, based on the starch blend, is established before the material leaves the extruder; where the starch-immiscible polymer is added in molten or granular form at any desired point in the extruder, and a mixture of all of the components present is consequently produced.

A three-dimensional (3D) drawing pen can include a housing that has a port that permits insertion of a strand of material into the housing, an actuator for controlling a movement of the strand, and a nozzle assembly configured to permit the strand to be extruded out of the 3D drawing pen in a form that retains its shape against gravity in free space to draw a 3D object.

An extruder screw conveying raw materials while kneading them includes a screw main body, conveyance portions, barrier portions, and paths. The conveyance portions convey the raw materials in an axial direction. The paths each include an entrance and an exit. The raw materials, the conveyance of which is limited by the barrier portions, flow in from the entrance. The raw materials flowing in from the entrance flow through the paths in an opposite direction to a conveyance direction. The exit is opened in the outer circumferential surface of the screw main body at a position outside the conveyance portions in which the entrance is opened.

The invention relates to a process for removal of volatile components from an olefin polymer, the process carried out in an extruder comprising at least one vacuum degassing zone, said process comprising the steps of: (a) introducing a stream of an olefin polymer into the extruder; (b) extruding the olefin polymer in the extruder at a temperature which is higher than the melting temperature of the olefin polymer but lower than the decomposition temperature of the olefin polymer, thereby producing an olefin polymer melt having reduced amount of volatile components, wherein the process in the extruder has a residence time distribution broadness (σ2) in the range of 800 to 4000 as define by equation (1) wherein: σ2 is the residence time distribution broadness, T is the mean residence time, t is the interval of residence time a fluid element of the olefin polymer spends in the extruder, E(t) is the residence time distribution function, and wherein the process optionally comprises a step (c) where the melt of the olefin polymer is passed through a die zone to a pelletizer for pelletizing the obtained olefin polymer.
σ.sup.2=∫.sub.0.sup.∞(t−τ).sup.2E(t)dt  equation (1)

A three-dimensional (3D) drawing pen can include a housing that has a port that permits insertion of a strand of material into the housing, an actuator for controlling a movement of the strand, and a nozzle assembly configured to permit the strand to be extruded out of the 3D drawing pen in a form that retains its shape against gravity in free space to draw a 3D object.

Methods for processing LDPE recyclates including, but not limited to, polyethylene and polypropylene and compositions therefrom are provided. LDPE recyclate can be visbroken to improve processing characteristics and/or devolatilized to remove waste byproducts to produce processed LDPE recyclates. Processed LDPE recyclates are compounded with pre-consumer polyolefins to produce blend compositions having acceptable or even improved processing characteristics. Such pre-consumer polyolefins can also be visbroken to further tailor processing characteristics of such polymer blends. A combination of extruders and/or extruder zones can be used at the same or different locations for visbreaking and/or compounding of both LDPE recyclate and/or pre-consumer polyolefins.

Methods for processing HDPE and/or MDPE recyclates including, but not limited to, polyethylene and polypropylene and compositions therefrom are provided. HDPE and/or MDPE recyclate feedstocks can be visbroken to improve processing characteristics and/or devolatilized to remove waste byproducts to produce processed HDPE recyclate and/or processed MDPE recyclates. Processed HDPE recyclate and/or processed MDPE recyclates are compounded with pre-consumer polyolefins to produce blend compositions having acceptable or even improved processing characteristics. Such pre-consumer polyolefins can also be visbroken to further tailor processing characteristics of such polymer blends. A combination of extruders and/or extruder zones can be used at the same or different locations for visbreaking and/or compounding of both HDPE and/or MDPE recyclate and/or pre-consumer polyolefins.

Methods for processing HDPE recyclates including, but not limited to, polyethylene and polypropylene and compositions therefrom are provided. HDPE recyclate can be visbroken to improve processing characteristics and/or devolatilized to remove waste byproducts to produce processed HDPE recyclates. Processed HDPE recyclates are compounded with pre-consumer polyolefins to produce blend compositions having acceptable or even improved processing characteristics. Such pre-consumer polyolefins can also be visbroken to further tailor processing characteristics of such polymer blends. A combination of extruders and/or extruder zones can be used at the same or different locations for visbreaking and/or compounding of both HDPE recyclate and/or pre-consumer polyolefins.

An apparatus including a three-dimensional (3D) drawing pen can permit a user to draw in free space to form a 3D object. The 3D drawing pen can include a housing, an actuator, and a nozzle assembly. The housing is configured to receive material therein and fit in a user's hand. The actuator is coupled to the housing and is configured to control a movement of the material. The nozzle assembly is configured to permit the material to be extruded to permit the user to form the three-dimensional object.