A method of making thin, annular multilayer coextruded films uses a layer sequence repeater module that includes a cell formed of a plurality of thin annular disks stacked on top of each other in an axial direction of the co-extrusion die. Each disk includes a plurality of openings aligned with openings in the adjacent disks, thus forming multiple inner and outer melt passages. At least one cell of the layer sequence repeater module includes at least one first cap disk, at least one second cap disk, at least one distribution disk, at least one repeater disk and at least one spreader disk. The layer sequence repeater module may be a separately assembled and individually removable module of the co-extrusion die. Alternatively or additionally, the layer sequence repeater module may be incorporated into a module of the co-extrusion die.

A novel tubular or profile shapes of co-extruded multilayer polymers. These materials contain tens to thousands of layers of milli-, micro- to nano-polymer layers. These new shapes contain contiguous layers of milli- to nano-polymer layers in three dimensions and these contiguous layers may be twisted or turned to further expand the potential microlayer geometries.

In one embodiment, a method of forming an extruded board includes mixing a resin and a foaming agent, melting the mixed resin and foaming agent to form a uniformly colored extrudate, differentially expanding voids formed from the foaming agent within the uniformly colored extrudate by passing the uniformly colored extrudate through a breaker plate, forming a board with the differentially expanded voids and uniformly colored extrudate, and forming lightened portions on an outermost surface of the formed board.

A multilayer film includes an extruded first polymer layer confined between extruded second polymer layers. The first polymer layer includes a high aspect ratio crystalline lamellae. The multilayer film is substantially impermeable to gas diffusion.

Embodiments of the present invention include a novel interfacial surface generator (ISG) design comprised of helical channels and associated methods of using the new design. The novel design addresses processing challenges associated with conventional ISG designs used in layer multiplying coextrusion systems. Embodiments of the present invention may be used in either a static configuration or active configuration. In one active configuration, two counter-rotating cylindrical rods and/or moving belts may be used to induce drag, or Couette, flow. Conveyance of materials through the ISG may be due to pressure driven flow, drag flow, or a combination of these.

Embodiments of the present invention include a novel interfacial surface generator (ISG) design comprised of helical channels and associated methods of using the new design. The novel design addresses processing challenges associated with conventional ISG designs used in layer multiplying coextrusion systems. Embodiments of the present invention may be used in either a static configuration or active configuration. In one active configuration, two counter-rotating cylindrical rods and/or moving belts may be used to induce drag, or Couette, flow. Conveyance of materials through the ISG may be due to pressure driven flow, drag flow, or a combination of these.

A method of producing a stretch film includes at least: extruding a first random copolymer polypropylene (RCPP) resin from a first extruder at a first temperature to at least one primary channel inside of a feedblock; extruding a second RCPP resin from a second extruder at a second temperature to at least one secondary channel, wherein said second temperature is greater than said first temperature; combining the first RCPP resin and the second RCPP resin to create a layered stream using a combining adapter disposed in communication with the feedblock; passing said layered stream from the combining adapter to a die; and passing the layered stream through said die to a casting unit. A multi-layered stretch film includes at least one nanolayer section, the nanolayer section comprising alternating substantially adjacent layers of a first random copolymer polypropylene (RCPP) resin and a second RCPP resin.

A method of producing a stretch film includes at least: extruding a first random copolymer polypropylene (RCPP) resin from a first extruder at a first temperature to at least one primary channel inside of a feedblock; extruding a second RCPP resin from a second extruder at a second temperature to at least one secondary channel, wherein said second temperature is greater than said first temperature; combining the first RCPP resin and the second RCPP resin to create a layered stream using a combining adapter disposed in communication with the feedblock; passing said layered stream from the combining adapter to a die; and passing the layered stream through said die to a casting unit. A multi-layered stretch film includes at least one nanolayer section, the nanolayer section comprising alternating substantially adjacent layers of a first random copolymer polypropylene (RCPP) resin and a second RCPP resin.

In one embodiment, a method of forming an extruded board includes mixing a resin and a foaming agent, melting the mixed resin and foaming agent to form a uniformly colored extrudate, differentially expanding voids formed from the foaming agent within the uniformly colored extrudate by passing the uniformly colored extrudate through a breaker plate, forming a board with the differentially expanded voids and uniformly colored extrudate, and forming lightened portions on an outermost surface of the formed board.

A system and method are presented in which a flow of plastic is extruded to obtain nano-sized features by forming multiple laminated flow streams, flowing in parallel through the non-rotating extrusion system. Each of the parallel laminated flow streams are subjected to repeated steps in which the flows are compressed, divided, and overlapped to amplify the number of laminations. The parallel amplified laminated flows are rejoined to form a combined laminated output with nano-sized features. The die exit is formed to provide a tubular shape.