Elastomer composition having a self-sealing property which can be used in particular as puncture-resistant layer in an inflatable article, based on at least (phr meaning parts by weight per 100 parts of solid elastomer): a blend of at least two solid elastomers, a polybutadiene or butadiene copolymer elastomer, referred to as elastomer A, and a natural rubber or synthetic polyisoprene elastomer, referred to as elastomer B, the elastomer A: elastomer B ratio by weight being within a range from 10:90 to 90:10; between 30 and 90 phr of a hydrocarbon resin; from 0 to less than 30 phr of filler. Inflatable article, such as a tire, provided with a puncture-resistant layer comprising this elastomer composition; the puncture-resistant layer is advantageously used in combination with an airtight layer, for example based on butyl rubber or TPS elastomer, in order to form, in the inflatable article, an airtight and puncture-resistant laminate.

A method for the improved extrusion of polyethylene polymers comprising passing polyethylene through a single stage, twin screw extruder comprising a solid polymer conveying zone, a polymer melting zone, a dispersive mixing zone, and a distributive mixing/pumping zone, in which the throughput and screw speed are optimized to reduce the number of gels present, ensure complete polymer melting within the polymer melting zone, and to minimize polymer degradation.

An extruder screw includes a screw main body, conveyance portions, barrier portions, and paths. 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 of the conveyance portions. The exit is opened in the outer circumferential surface of the screw main body at a position on an upstream side in the conveyance direction in the conveyance portions in which the entrance is opened.

A mixing segment for an extrusion apparatus comprises a shaft and a plurality of plow elements aligned along a helical path extending about a rotation axis of the shaft. Each plow element includes an outer peripheral arcuate ramp extending radially outwardly along the helical path from a root to an outer tip of the plow element. Methods of manufacturing a mixing segment and methods of manufacturing a honeycomb structure with an extrusion apparatus are also provided.

The present invention relates to a process for devolatilising polymer-containing media such as, in particular, polymer melts, polymer solutions and dispersions and also devolatilisation apparatuses for carrying out the abovementioned process.

A kneading apparatus includes a processor, and a extruder. The extruder includes a screw. The screw includes a screw main body. A conveyance portion, a barrier portion, and a path are provided at places of the screw main body. In at least one of the places, the path is provided inside the screw main body, and includes an entrance and an exit. The raw materials, pressure on which is increased by the barrier portion, flow in from the entrance. The raw materials flowing in from the entrance flow through the path toward the exit. The exit is positioned to be remote from the entrance in an axial direction.

A conveyance portion, a barrier portion, and a path are provided at places of a portion of a screw main body in which a kneading portion is provided. In at least one of the places, an entrance is opened to cause raw materials, conveyance of which is limited by a barrier portion to increase pressure on the raw materials, to flow in. The raw materials flowing in from the entrance flow through the path in the opposite direction to a conveyance direction of the conveyance portion. An exit is opened in an outer circumferential surface of the screw main body at a position outside the conveyance portion in which the entrance is opened.