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).

A film-making machine that produces stretch film includes an outlet device with an outlet gap for outlet of free-flowing film material and a rotatably mounted casting roll that receives the released free-flowing film material on a surface of the casting roll, and a cleaning device with a rotatably mounted cleaning roll that contacts the film material lying on the surface of the casting roll, wherein the cleaning device has an adjusting mechanism with a circumferential adjustment that adjusts a cleaning position of the cleaning roll along a circumferential direction of the casting roll.

A film is manufactured from a semi-crystalline plastics material by a method with multiple steps. In step a, the film is shaped using a calender, in which a melt coming from a slotted nozzle is introduced into a nip between two cooling or calibrating rollers. The film is calendered between the two cooling or calibrating rollers. In step b, The film is cooled in a cooling section, which has roller pairs arranged one after the other. A film temperature is changed by changing a temperature of downstream rollers, thereby achieving a maximum number of crystallization nuclei. The film temperature is detected using sensors. In step c, the film is cooled down further to a film temperature that allows the film to be spooled. The temperature of the film is kept in a defined temperature range between 128° C. and 138° C. in step b), thereby preventing the automatic formation of further crystals.

Apparatus and methods for producing multiple extruded products having different characteristics from the extruded stream of a single main extruder are provided. A satellite extruder assembly is removably attached to a main extruder allowing for the production of a plurality of different extrusion products from a single stream from one main extruder that is divided into multiple streams channeled to a plurality of satellite extruders. Each of the extruders may be operated at different temperature, pressure, moisture and shear conditions. Additional components may be selectively added to one or more of the material streams.

A group of hollow modules through which the material to be extruded flows, is provided that includes at least: a rectangular heating-shaping module, in which the material undergoes a temperature increase and takes on the desired shape; and a tubular cooling-solidification module, in which the material changes from liquid to solid. A heating-reaction module is provided upstream of the heating-shaping module. The heating-reaction module includes an interchangeable hollow tube with an external heating system. The heating-shaping module includes detachable parts and includes another external heating system based on the auto-acceleration of the curing reaction and of the heat supply from said external heating system. The tubular portion between the heating-reaction module and the heating-shaping module includes a shaping coupling equipped with a through-hole. The extrusion module includes a circuit through which the polymer flows into at least two push compartments.

An apparatus (1) for optical inspection of a mass of polymeric material (2) passing through an extruder (3) having a hollow extrusion cylinder (4) extending elongately in a longitudinal direction comprises an optical sensor (8) which can be operatively coupled to the extrusion cylinder (4) and having an infrared light emitter (8a) and a receiver (8b) configured to measure a measurement parameter representing an optical property of the polymeric material (2) inside the extrusion cylinder (4) and is characterized in that it comprises a plurality of the optical sensors (8) which can be operatively coupled to the extrusion cylinder (4) in a plurality of measurement sites located in succession and spaced from each other along the longitudinal direction and a processor (9) programmed to acquire a plurality of measurement signals containing the measurement parameters measured by the corresponding optical sensors (8) and programmed to process the plurality of measurement signals in order to calculate a corresponding plurality of values of a control parameter indicating a physical state of the polymeric material (2) as a function of a longitudinal position.

Disclosed are a system and method tuning PET raw material processing process by employing real time process management and machine learning steps and reactive addition of dosing of homogenizing composition for impregnating chain extenders and compatibilizing agents in thermoplastic resin using the liquid additive as a carrier into the process for modifying material performance. The properties of PET blend are no longer fixed once dry-blending and melting is complete.

A film-making machine that produces stretch film includes an outlet device with an outlet gap for outlet of free-flowing film material and a rotatably mounted casting roll that receives the released free-flowing film material on a surface of the casting roll, and a cleaning device with a rotatably mounted cleaning roll that contacts the film material lying on the surface of the casting roll, wherein the cleaning device has an adjusting mechanism with a circumferential adjustment that adjusts a cleaning position of the cleaning roll along a circumferential direction of the casting roll.

A paperboard substrate that can be used to provide a food packaging particle is provided having a water vapor barrier layer comprising HDPE in combination with a nucleating agent which is extruded on to a paperboard substrate. The resulting substrate has sufficiently good water vapor barrier when properties that dry foods such as cereals do not require a bag or inner liner as a separate moisture barrier.