Abstract: A rotary processor for high-shear processing of plastic or polymeric materials comprises a rotor having end discs and at least one mixing disc therebetween, the rotor closely surrounded by a housing to defined annular processing chambers flanking each mixing disc, with a high-shear-mixing transfer gap defined between the mixing disc and the housing. Channel blocks are deployed at circumferentially spaced apart positions in adjacent chambers to cause transfer of material through the transfer gaps, with dispersive mixing occurring in the transfer gaps. Some embodiments have plural channel blocks in the chambers, evenly spaced apart. The channel blocks extend generally into and to the bottom of a chamber, and have two working surfaces divergent from a central region of the chamber and convergent toward the disc walls defining the chamber. The working surfaces and disc walls defined two high-shear-mixing recycle gaps through which a portion of the material passes and is mixed.

Abstract: A method for measuring the viscosity of a foamable plastics melt where accurate readings are difficult because of the melt material beginning to foam while in the rheometer test section slit. The pressure on the melt is elevated above the foaming point and maintained at an elevated level during the entire time during which the melt sample is diverted through the rheometer.

Abstract: A novel, improved rotary processor comprising a rotatable element carrying a plurality of processing channels and a stationary element having a coaxial closure surface operationally arranged with the channels to provide a plurality of enclosed processing passages. The plurality of passages provide interconnected processing stages including a first processing stage and a second processing stage having inboard and outboard sections separated by a third processing stage.