A method for producing a fused unplasticised polyvinyl chloride (UPVC) article (126) is provided. The method includes feeding an UPVC blend (103) into a co-rotating twin-screw extruder (100). The method further includes melting the UPVC blend (103) and conveying fused UPVC to an outlet (120) of the co-rotating twin-screw extruder (100). The method also includes collecting the fused UPVC from the outlet (120) at a rate of at least 100 kilograms/hour per litre of free volume (124) of the co-rotating twin-screw extruder (100).

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)

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 screw includes a screw main body, a conveyance portion conveying a raw material, and a passage provided in the screw main body. The passage includes a first passage element, a second passage element, and a third passage element. The screw main body has a plurality of cylindrical bodies arranged in an axial direction of the rotating shaft. At least a portion of the conveyance portion is formed on outer peripheral surfaces of the cylindrical bodies adjacent to each other, and the passage is formed in the cylindrical body so as to cross over between the adjacent cylindrical bodies.

Disclosed is a recycling apparatus for a cross-linked polyethylene resin using a twin screw extruder. The recycling apparatus for a cross-linked polyethylene resin using a twin screw extruder according to an embodiment of the present disclosure includes: a raw material supply unit configured to supply a raw material that is a cross-linked polyethylene resin; and a twin screw extruder configured to receive the raw material from the raw material supply unit, the twin screw extruder including a cylinder and a twin screw installed inside the cylinder to rotate in the same direction, the twin screw extruder being configured to de-crosslink and recycle the raw material under a de-crosslinking reaction temperature and reaction pressure atmosphere while continuously transporting the raw material along the twin screw by the rotation of the twin screw.

Disclosed is a recycling apparatus for a cross-linked polyethylene resin using a twin screw extruder. The recycling apparatus for a cross-linked polyethylene resin using a twin screw extruder according to an embodiment of the present disclosure includes: a raw material supply unit configured to supply a raw material that is a cross-linked polyethylene resin; and a twin screw extruder configured to receive the raw material from the raw material supply unit, the twin screw extruder including a cylinder and a twin screw installed inside the cylinder to rotate in the same direction, the twin screw extruder being configured to de-crosslink and recycle the raw material under a de-crosslinking reaction temperature and reaction pressure atmosphere while continuously transporting the raw material along the twin screw by the rotation of the twin screw.

The disclosure relates to oxygen scavenging compositions, methods of making the compositions, articles prepared from the compositions, and methods of making the articles. This abstract is intended as a scanning tool for purposes of searching in the particular art and is not intended to be limiting of the present invention.

A device for producing dyed plastic granulate and undyed plastic granulate includes a multi-shaft screw extruder and an underwater pelletizing installation. A granulate changeover unit which separates the dyed plastic granulate from the undyed plastic granulate is disposed in a conveying direction downstream of the underwater pelletizing installation. The dyed plastic granulate is separated from the pelletizing water via a first separator installation, and the undyed plastic granulate is separated from the pelletizing water via a second separator installation. The separator installations are disposed so as to be mutually parallel. The device enables a simple, flexible and economical selective production of the dyed plastic granulate and the undyed plastic granulate.

A device for producing dyed plastic granulate and undyed plastic granulate includes a multi-shaft screw extruder and an underwater pelletizing installation. A granulate changeover unit which separates the dyed plastic granulate from the undyed plastic granulate is disposed in a conveying direction downstream of the underwater pelletizing installation. The dyed plastic granulate is separated from the pelletizing water via a first separator installation, and the undyed plastic granulate is separated from the pelletizing water via a second separator installation. The separator installations are disposed so as to be mutually parallel. The device enables a simple, flexible and economical selective production of the dyed plastic granulate and the undyed plastic granulate.

The present invention relates to a polymer composition comprising (A) from 60 to 90 wt % of a non-elastomeric polyethylene; (B) from 9.0 to 38 wt % of an elastomer; wherein onto component (A) or components (A) and (B) an acid grafting agent (C) has been grafted in an amount of from 0.01 to 3.0 wt %, all based on the total weight of the polymer composition, and wherein the polymer composition has two distinct peaks and a valley between said peaks in the GPC curve and a Z value, determined from the areas below the two peaks of the GPC curve, of at least −0.3, wherein the Z-value is determined according to formula (I) Z=s/Abs(B−A) (I) wherein Abs(B−A) is the absolute value of (B−A); A=the area, between the tangent parallel to the MW axis going through log M (Min) and the LS15 signal, from log M of 5.1 to log M value where the LS signal is minimum log M (Min), in the log M range between 5.1 and 6; B=the area, between the tangent parallel to the MW axis going through log M (Min) and the LS 15 signal, from log M(Min) to the point where the LS signal is crossed again; and s is the slope between the two peaks of the GPC curve, defined at log M of 5.1 and 6, wherein the GPC curve is defined as the concentration normalized LS 15 signal along the molecular weight of conventional GPC, obtained from the GPC-VISC-LS analysis, a multi-layer structure such as a coated metal pipe, comprising one layer comprising said polymer composition and the use of said polymer composition as adhesive polymer composition and for the production of a multi-layer structure.