A system for manufacturing a catheter includes at least first and second controllable rate material feeders that feed at least first and second materials into a temperature-controlled mixer to form a compound material that varies in flexibility and/or strength with the respective first and second materials and material feed rates. An extruder extrudes the compound material onto a rotating and translating mandrel to thereby form a variable stiffness profile along a length of the catheter that depends on respective rates of rotation and translation of the mandrel.

A ram extrusion apparatus including a die having several thermal zones, a hopper for introducing a granular polymer resin to the die, and a ram for moving the granular polymer resin through the thermal zones of the die and out from an outlet end thereof at a temperature above the crystalline melt temperature of the polymer resin. The hopper may be designed to deliver the polymer resin into a resin inlet of the die in a plurality of specifically metered amounts which may vary across a width of the resin inlet end of the die. The apparatus may further include one or more finishing tables positioned after the outlet end of the die for receiving and moving the extruded resin away from the outlet end of the die so that there is no backpressure on the extruded resin, and which provide compression force and even cooling to the extruded resin.

A method of manufacturing bulked continuous carpet filament that includes providing a polymer melt and separating the polymer melt from the extruder into at least eight streams. The multiple streams are exposed to a chamber pressure within a chamber that is below approximately 25 millibars, or another predetermined pressure. The streams are recombined into a single polymer stream. Polymer from the polymer stream is then formed into bulked continuous carpet filament.

Novel aromatic polyimides are disclosed with sufficient physical properties to be useful in 3D printing.

A weighing apparatus for the preparation of a mixture of granular components that comprise batches of material required by a plurality of processing machines in a plant for the manufacture of plastic products is described. The apparatus comprises a Multi-Channel Gravimetric Batch Blender (MCGBB) configured to weigh predetermined weights of the raw materials and to combine the weighed portions of raw materials into batches according to a predetermined recipe for each processing machine and a computer that controls the operation of all components of the MCGBB. The MCGBB comprises several weighing units arranged in a way that allows material weighed in each of the weighing units to fall through individual chutes via a common funnel into a manifold that distributes the weighed batches to several processing machines via a system of delivery pipes.

A composition includes (a) a polypropylene or a polypropylene copolymer, (b) a polyol, and (c) optionally an organic peroxide. The polyol (b) is in the range of from about 0.01 wt. % to about 25 wt. % of the total weight of (a), (b) and (c). The method of making such a polymer composition, the method of using such a polymer composition, and a sheet or a fabricated article comprising such a polypropylene composition, are also provided.

Method and apparatus for air flow regulation comprise a vertically oriented conduit, a sail assembly positioned in the conduit and moveable therewithin responsively to air flow through the conduit to regulate rate of air flow through the conduit and to stop air flow through the conduit upon air flow rate through the conduit exceeding a preselected value with a detector for sensing when the sail assembly has stopped air flow thought the conduit as a result of air flow rate exceeding said pre-selected value.

Novel aromatic polyimides are disclosed with sufficient physical properties to be useful in 3D printing.

A self-cleaning dosing apparatus includes a material hopper for containing pellets of material, a feed screw, a first material outlet through which pellets of material fall by gravity onto a first end of the feed screw for the feeding of pellets to a process machine. A second material outlet is located beneath the first end of the feed screw, with a slide gate blocking the second material outlet. A pneumatic piston is provided for pulling the slide gate to unblock the second material outlet, and a Venturi pump is located under the second material outlet for pulling pellets through the second material outlet when the slide gate is opened.

A system and process for producing a homogenous extrudate powder coating composition having predetermined properties, the system comprising a color library database that is configured to store one or more input formulation data objects capable of use in controlling the inputs and operation of an electronically controlled homogenous extrudate mixer.