A method of making a tie strip from as stretch-orientable thermoplastic comprising a series of joined unit cells, wherein the moulding material is injected into the mould at multiple gating points along the strip to introduce flow discontinuities thereby to localise regions for stretch orientation.

A micro-voided film comprising high density polyethylene having a molecular weight of at least about 200,000, and low aspect ratio filler having a mean particle size from about 1 to about 25 microns. The film has a thickness of from about 0.1 to about 20 mils and a void fraction of from about 0.60 to about 0.75. The micro-voided film is made by a process comprising extruding the composition into a film having a thickness of from about 20 to about 200 mils, and orienting the extruded film using a high stalk, blown film process. The process produces a stabilized high stalk for increasing the production rate of blown, high molecular weight polyethylene, while increasing the film's physical and mechanical properties. The high stalk can be stabilized by application of high velocity, low volume flow rate of air over the interior and exterior surfaces of the extruded film.

In some examples, a method including depositing a resin and a plurality of carbon fibers via a print head of a three-dimensional printing system to form a carbon fiber preform including a plurality of individual carbon fiber layers, wherein each individual layer of the plurality of individual carbon fiber layers includes the resin and carbon fibers, and wherein the carbon fiber preform exhibits at least one of a non-uniform composition of the resin within the preform, different types of the carbon fibers within the preform, or non-uniform fiber orientation within the preform.

A method of forming a confined crystallization multilayer film includes coextruding a plurality of first polymer layers and a plurality of second polymer layer to form a multilayer film wherein each first polymer layer is sandwiched between second polymer layers and axially orienting the multilayer film at a temperature below the melting temperature (T.sub.m) of the second polymer layer and to a thickness such that each first polymer layer forms a high aspect ratio substantially crystalline lamellae.

A composite material of particles disposed in a matrix material is provided in which the particles have an asymmetric geometric shape with a longest dimension and a shortest dimension different from the longest dimension. Adjacent volume portions of the composite material are arranged in a mosaic pattern to abut along an interface or surface forming a common boundary between the adjacent volume portions. The particles within the adjacent volume portions are arranged with differing orientations with respect to the interface. The orientations of the particles in the adjacent volume portions are selected so that a crack propagating on a crack propagation path through one or the other of the adjacent volume portions stops at or deflects to propagate along the interface. Methods of making composite materials are also provided.

An apparatus and method for producing oriented polymer films are disclosed. The apparatus includes a curved enclosure configured to rotate and a flow obstacle. The curved enclosure has an interior volume with an opening at one end. The flow obstacle extends through the opening and interior volume, with one end rigidly coupled to a mounting plate. The flow obstacle's position is adjustable to contact the interior surface of the curved enclosure, defining a gap between them. The method involves introducing a material into the curved enclosure, adjusting the flow obstacle's position, and rotating the curved enclosure to generate an extensional flow within the material. The apparatus and method may be used for producing two-dimensional polymer films and can incorporate features such as inert gas flushing, heating systems, and various blade configurations for the flow obstacle.

A method (300) of additively manufacturing a composite part (102) comprises depositing a segment (120) of a continuous flexible line (106) along a print path (106). The continuous flexible line (106) comprises a non-resin component (108) and further comprises a photopolymer-resin component (110) that is uncured. The method (300) further comprises delivering a predetermined or actively determined amount of curing energy (118) at least to a portion (124) of the segment (120) of the continuous flexible line (106) at a controlled rate while advancing the continuous flexible line (106) toward the print path (122) and after the segment (120) of the continuous flexible line (106) is deposited along the print path (122) to at least partially cure at least the portion (124) of the segment (120) of the continuous flexible line (106).

A method (400) of additively manufacturing a composite part (102) comprises applying a thermosetting resin (252) to a non-resin component (108) to create a continuous flexible line (106) by pulling a non-resin component (108) through a first resin-part applicator (236), in which a first quantity of a first part (253) of the thermosetting resin (252) is applied to the non-resin component (108), and by pulling a non-resin component (108) through a second resin-part applicator (237), in which a second quantity of a second part (255) of the thermosetting resin (252) is applied to at least a portion of the first quantity of the first part (253) of the thermosetting resin (252), applied to the non-resin component (108). The method (400) further comprises routing the continuous flexible line (106) into a delivery guide (112) and depositing, via the delivery guide (112), a segment (120) of the continuous flexible line (106) along a print path (122).

A method (300) of additively manufacturing composite part (102) comprises depositing a segment (120) of a continuous flexible line (106) along a print path (122). The continuous flexible line (106) comprises a non-resin component (108) and further comprises a photopolymer-resin component (110) that is uncured. The method (300) further comprises delivering a predetermined or actively determined amount of curing energy (118) at least to a portion (124) of the segment (120) of the continuous flexible line (106) at a controlled rate while advancing the continuous flexible line (106) toward the print path (122) and after the segment (120) of the continuous flexible line (106) is deposited along the print path (120) to at least partially cure at least the portion (124) of the segment (120) of the continuous flexible line (106).

A method (300) of additively manufacturing a composite part (102) comprises depositing a segment (120) of a continuous flexible line (106) along a print path (122). The continuous flexible line (106) comprises a non-resin component (108) and a photopolymer-resin component (110) that is partially cured. The method (300) also comprises delivering a predetermined or actively determined amount of curing energy (118) at least to a portion (124) of the segment (120) of the continuous flexible line (106) at a controlled rate while advancing the continuous flexible line (106) toward the print path (122) and after the segment (120) of the continuous flexible line (106) is deposited along the print path (122) to at least partially cure at least the portion (124) of the segment (120) of the continuous flexible line (106).