Foster-miller, Inc.

Albany International Research Company, Inc.

Superex Polymer, Inc.

United States of America As Represented by the Secretary of the Air Force

Richard W Lusignea

Andrew Cecil Harvey

Leslie S Rubin

Robert B Davis

Donald D Bretches

James L Racich

Dirk M Baars

Robert F Kovar

Joseph W Piche

R Ross Haghighat

Paul J Glatkowski

William A Stevenson

John F McCoy, Iii

David A Evans

Kent G Blizard

Charles F Mariano

Kumaraswamy Jayaraj

James M Burnett

Uday Kashalikar

Joseph J Stanco

Ross R Haghighat

Ruby R Chandy

George J Kirby

William S Stevenson

This invention relates in general to the formation of thick films having a biaxial molecular orientation. Such films are prepared in accordance with the present invention from rod-like extended chain aromatic-heterocyclic ordered polymers. Such films have high tensile strength, modulus, and environmental resistance characteristics. A preferred ordered polymer for use in the present invention is poly (para-phenylenebenzo bisthiazole), (PBT), a compound having the structure: ##STR1## The present invention is also directed to methods and apparatus suitable for producing biaxially oriented films, coatings, and like materials from ordered polymers, preferably PBT.

Biaxially oriented ordered polymer films

A flat and nearly mechanically isotropic polymer film or sheet, or a tube, can be formed by laminating two or more films, preferably by coextrusion of a liquid crystal polymer film and a thermoplastic polymer film. A liquid crystal polymer layer may be combined with one or more thermoplastic polymer layer in various arrangements. The liquid crystal, and possibly the thermoplastic as well, may have a controlled molecular orientation. The film may be formed by passing a polymer through a set of two or three tubular rotors which are concentric and have facing surfaces which define inner and outer annular polymer flow channels.

Coextrusion of liquid crystal polymers and thermoplastic polymers

This invention relates in general to capacitors including one or more layers of dielectric material wherein at least one of the layers including a multiaxially oriented lyotropic liquid crystalline polymer (LCP) film. The present invention also provides lyotropic LCPs films having less than 0.5% residual ionic contaminants and a method of preparing such films and capacitors including such films. In preferred embodiments, the invention further provides a capacitor wherein the liquid crystalline polymer film has less than 0.5% residual ionic contaminants.

Liquid crystalline polymer capacitors

The present invention relates to articles of manfacture, such as films, tubes, and coatings, comprising a multiaxially oriented film having a planar morphology, wherein the article of manfacture comprises at least one thermoplastic flexible polymer, at least one thermotropic liquid crystalline polymer, or a blend thereof. Recyclable articles of manufacture having improved barrier properties are also provided.

Extruded thermoplastic, liquid crystalline polymers and blends thereof

Coatings of multiaxially oriented Thermotropic Liquid Crystalline Polymer (TLCP) are provided to elongated members. Suitable members include glass rods, glass fibers, pipes, beams, and other oval or polygonal members having an essentially regular cross-section. Members of ceramic, plastic, or metal can also be coated. This extrusion is performed using a die having inner and outer mandrels capable of rotating in opposite directions. Concentricity between inner and outer mandrels of the die is maintained to assure uniform coating thickness. In order to produce a high level of multiaxial orientation at lower die rotational speeds, the die design may include spiraling feed zones on one or both facing surfaces of the inner and outer mandrels. The application of the multiaxially oriented coating provides superior impermeability to water vapor and oxygen, and increased strength to the elongated member in the axial direction.

Members having a multiaxially oriented coating of thermotropic liquid

A flat and nearly mechanically isotropic polymer film or sheet, or a tube, can be formed by laminating two or more films, preferably by coextrusion of a liquid crystal polymer film and a thermoplastic polymer film. A liquid crystal polymer layer may be combined with one or more thermoplastic polymer layer in various arrangements. The liquid crystal, and possibly the thermoplastic as well, may have a controlled molecular orientation. The film may also be formed by passing a polymer through a set of two or three tubular rotors which are concentric and have facing surfaces which define inner and outer annular polymer flow channels.

Coextrusion of liquid crystal polymers and thermoplastic polymers to

Film-based composite structures meet the requirements of highly weight-efficient SDI space-based systems. These structures are rigid, lightweight, dimensionally stable, and possess a high degree of structural damping. Thin-walled structures (wall thickness less than 50 .mu.) made from self-reinforced ordered-polymer films overcome drawbacks of fiber-reinforced composites, and provide resistance to microcracking, ply delamination and impact. They have high temperature capability (over 300.degree. C.), low temperature (cryogenic) capability and the capability for hardening and survivability. The modulus and dimensional stability of film-based ultralightweight honeycomb sandwich structures is better than currently possible with aluminum or fiber-reinforced composite materials. Other thin-walled structures such as tension web beams and thin facesheets also show similar stiffness-to-weight advantages over current materials.

Film-based composite structures for ultralightweight SDI systems

Provided are methods for laminating ordered polymers such as PBZT/sol-gel glass microcomposite film layers by first roughing the bonding surfaces of such film layers and then inserting therebetween a PEEK resin adhesive layer and compressing the film and adhesive layers together at sufficient temperature and pressure to laminate such layers. In one embodiment the ordered polymer layers are hot-pressed before surface roughing, stacking and laminating of film and adhesive layers. The invention also includes the novel laminates prepared thereby which exhibit high tensile strength, high compressive strength and good interlaminar strength, suitable for high-performance structures in e.g. aircraft, spacecraft or other structures or vehicles.

Ordered polymer/sol-gel microcomposite laminates with peek resin adhesive

Liquid crystal polymer film

Processes for producing oriented films of semicrystalline thermoplastic polymers, such as polyimides, and films produced thereby are disclosed. One process includes partial crystallization or imidization, orientation and further crystallization or imidization. Another process includes rendering a film of semicrystalline thermoplastic polymer amorphous, orienting the film and introducing crystallinity.

Oriented semicrystalline polymer films

The vessel structures disclosed herein are adapted for containing a mobile or highly permeating fluid such as helium gas or liquid hydrogen or oxygen. Escape of the fluid is inhibited by a barrier layer of an oriented lyotropic liquid crystal polymer film. Preferred polymers include polybenzazole (PBZ) polymers.

Vessel construction

The present invention is based upon the discovery that ordered polymers, such as PBzT, can be readily formed into tubular structures which retain a biaxial orientation imparted thereto during processing, and that these rigid, high-stiffness tubular components can exhibit near zero coefficient of thermal expansion (CTE). Zero CTE materials are not adversely affected by vast swings in temperature, e.g., from very hot to very cold in short periods of time, nor are they adversely affected by long term exposure to either temperature extreme. The tubular components of the present invention thus represent a revolutionary advance in space based hardware, as the extreme temperatures experienced there will not affect rigidity of structures built using these components.

Molecularly oriented tubular components having a controlled coefficient

The present invention is directed to the use of multiaxially oriented (e.g., biaxially) thermotropic polymers as a substrate material for the preparation of printed wire boards (PWB). In preferred embodiments, the PWB of the present invention comprises a generic, high density, organic multilayer PWB comprising XYDAR.RTM. and/or VECTRA.RTM. films, capable of being employed as a high density leadless perimeter and in grid array ceramic chip packages.

Multiaxially oriented thermotropic polymer substrate for printed wire

This invention relates in general to the formation of thick films having a biaxial molecular orientation. Such films are prepared in accordance with the present invention from rod-like extended chain aromatic-heterocyclic ordered polymers. Such films have high tensile strength, modulus, and environmental resistance characteristics. A preferred ordered polymer for use in the present invention is poly (para--phenylenebenzo bisthiazole), (PBT), a compound having the structure: ##STR1## The present invention is also directed to methods and apparatus suitable for producing biaxially oriented films, coatings, and like materials from ordered polymers, preferably PBT.

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Brighton, MA, United States of America

Richard W Lusignea