The present invention relates to a method of producing a powder coating material containing a fluororesin and a non-fluororesin. The method of producing a powder coating material includes kneading a raw material containing the fluororesin and the non-fluororesin with a kneading extruder equipped with a screw having a kneading zone, wherein a ratio of a length L.sub.K of the kneading zone to an effective length L.sub.S of the screw (L.sub.K/L.sub.S×100) is 21.0 to 50.0%.

A worm shaft for a mixing and kneading machine particularly for continual processing having a shaft bar, on the circumferential surface of which blade elements are arranged to be spaced apart from one another extending outwards from the circumferential surface of the shaft bar, wherein the blade elements are arranged on the circumferential surface of the shaft bar, at least in one section extending in the axial direction of the worm shaft, in two rows extending in the axial direction of the worm shaft, and wherein each of the blade elements of the at least one section extending in the axial direction of the worm shaft has an elliptic, oval, or biconvex outer peripheral surface in the top view.

A shearing part for a plasticising screw has at least one inlet channel and at least one outlet channel, which run helically around or parallel to the longitudinal axis (X) of the shearing part. The inlet channel is open upstream and closed downstream. The outlet channel is open downstream and closed upstream. The inlet outlet channels are arranged lying directly adjacent to one another and contiguous to one another, and are connected directly with one another fluidically, so that inflowing melt can flow over directly from the inlet channel into the outlet channel, wherein a flow direction transversely to longitudinal axis (X) of the shearing part is produced. The inlet channel has a depth (T) at which shearing action on the melt is substantially avoided. The outlet channel is configured as shearing surface, so that shearing action is present onto melt flowing through the outlet channel.

Provided is a screw that is for use in an injection molding machine and that makes it possible to benefit from the kneading effect of a multi-start screw while minimizing the received friction resistance. The screw for an injection molding machine is provided with a first stage 20 on the upstream side and a second stage 30 on the downstream side. The screw for an injection molding machine is characterized in that: the first stage 20 is provided with a compression section 22 comprising a main scraper 25 and an auxiliary scraper 26 having a smaller outer diameter than the main scraper 25; and the second stage 30 is provided with a multi-start screw section 31, said multi-start screw section being provided on the upstream side and comprising a plurality of scrapers, and a fin kneading section 32 provided downstream from the multi-start screw section.

A worm shaft for a mixing and kneading machine particularly for continual processing having a shaft bar, on the circumferential surface of which blade elements are arranged to be spaced apart from one another extending outwards from the circumferential surface of the shaft bar, wherein the blade elements are arranged on the circumferential surface of the shaft bar, at least in one section extending in the axial direction of the worm shaft, in two rows extending in the axial direction of the worm shaft, and wherein each of the blade elements of the at least one section extending in the axial direction of the worm shaft has an elliptic, oval, or biconvex outer peripheral surface in the top view.

The use of a hot-melt adhesive as a protective element for objects is disclosed, wherein the hot-melt adhesive contains over 80 wt. % of at least one modified polyolefin copolymer produced from a high-molecular-weight polyolefin copolymer by thermomechanical degradation of the polymer under shear stress and/or heating, wherein the viscosity of the copolymer is reduced, and up to 20 wt. % of additives and auxiliary substances, wherein the adhesive has a softening point from 70 to 150° C.

The invention focuses on a device for sequentially introducing additives in a polymer granulate and the use of the device for mixing the polymer granulate with the additives. The device consisting of a mixer with housing, comprising at least one mixer shaft attached in helix arranged non-continuous conveying pattern shapes, being rotated by a drive for the transport, whereby the mixer in the housing featuring an inlet for the polymer granulate to be mixed and each of the several subsequent inlets for the additive is followed by an outlet for the polymer granulate mixed with the additive, so that two or several mixing zones being formed in the mixer and whereby at least between at two mixing zones on the surface of the mixing shaft one section featuring a continuous screw conveyor instead of the non-continuous conveying pattern shapes, the section not being penetrable for returning solids from the subsequent mixing zone.

A mixing section for an extrusion screw has an inlet end and an outlet end as well as alternating wiping lands and barrier lands. The wiping lands have a greater helix angle than the barrier lands. The wiping lands and the barrier lands define inlet channels which narrow toward the outlet end and outlet channels which widen toward the outlet end. A helical pattern of mixing channels is cut into the wiping lands and the barrier lands. The mixing channels may be oriented generally at approximately right angles to the wiping lands and the barrier lands. A portion of the extrudate encounters the inside wall surfaces of the mixing channels and changes direction which improves the mixing of the extrudate.

An EVOH resin composition excellent in inorganic compound dispersibility and a method of producing an EVOH resin composition excellent in productivity and inorganic compound dispersibility are provided. The EVOH resin composition contains an EVOH resin (A) and an inorganic compound (B), and has a crystallinity of not lower than 36%. The EVOH resin composition is produced by: feeding an EVOH resin (A), an inorganic compound (B) and water (C) into a kneading apparatus including a screw-type side feeder (3); melt-kneading the resulting EVOH resin mixture while driving the screw-type side feeder (3); and expelling water vapor from the screw-type side feeder (3) to reduce the water content of the EVOH resin mixture to lower than 5 weight % while suppressing leakage of the EVOH resin kneaded body from the screw-type side feeder (3).

With a mixing and kneading machine (100), wherein a worm shaft (12) moves in a housing (10) in a rotating manner and moves back and forth in a translatory movement, receptacles for kneading elements (12) are distributed non-uniformly. It is thereby possible to equip the receptacles with varying numbers of kneading elements. Quick adaptation is also thereby possible. In one embodiment, the number of kneading elements even varies over the extension direction of the mixing and kneading machine (100).