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

Alphamicron, Inc.

Timothy J White

Loon-Seng Tan

David Huabin Wang

Jeong Jae Wie

Kyung Min Lee

Taylor H Ware

Michael E McConney

Tyler C Guin

Benjamin A Kowalski

Hilmar Koerner

Nicholas P Godman

Anesia D Auguste

Suk-Kyun Ahn

Bahman Taheri

Tamas Kosa

Timothy J Bunning

Ludmila Sukhomlinova

Vincent P Tondiglia

Shape-programmable liquid crystal elastomers. The shape-programmable liquid crystal elastomers being synthesized by filling an alignment cell with liquid crystal monomers. The liquid crystal monomers align to a surface of the alignment cell and then are polymerized with a dithiol chain transfer agent. The alignment cell is configured to impose a director orientation on a portion of the shape-programmable liquid crystal elastomer. For some embodiments, liquid crystal elastomer laminates are prepared by arranging a plurality of liquid crystal elastomers such that a director orientation of each liquid crystal elastomer of the plurality is in registered alignment with an adjacent liquid crystal elastomer of the plurality. The arrangement is secured and the plurality of liquid crystal elastomers cured.

Liquid crystal elastomers

A shape-programmable liquid crystal elastomer. The elastomer comprising cross-linked and polymerized nematic, isotropic monomers with carbon nanotubes that are organized into a plurality of voxels. Each voxel has a director orientation such that each voxel of the plurality has a first state according to the director orientation and a second state according to cross-linkages of the polymerized nematic monomers. The elastomer transitions between the first and second states with exposure to an electric field.

Programmable nanocomposites

A shape-programmable liquid crystal elastomer comprises polymerized, nematic monomers. The monomers are organized into a plurality of voxels with each voxel having a director orientation.

Voxelated liquid crystal elastomers

A method of making a shape-programmable liquid crystal elastomer. The method includes preparing an alignment cell having a surface programmed with a plurality of domains. A cavity of the alignment cell is filled with a monomer solution. The monomers of the monomer solution are configured to align to the surface of the alignment cell. The aligned monomers are polymerized by Michael Addition. The polymerized monomers are then cross-linked to form a cross-linked liquid crystal elastomer. The cross-linking traps monomer alignment into a plurality of voxels with each voxel having a director orientation.

Methods of making voxelated liquid crystal elastomers

Bis(azo-benzene) diamine monomers and a method of synthesizing the monomers are provided. The bis(azo-benzene) diamine monomers, in combination with amine reactive monomers, form polymers, such as polyimides and copolyimides, having photomechanical and thermomechanical properties.

Bis(azobenzene) diamines and photomechanical polymers made therefrom

Compositions of azobenzene-containing, photomechanically active, copoly(amic acids) and linear copolyimides including an azobenzenediamine, a rigid dianhydride, and a flexible dianhydride are provided; and methods of making the same.

Photomechanically active copolyimides derived from an azobenzenediamine, a rigid dianhydride, and a flexible dianhydride

This application discloses a method of photomechanically manipulating optically fixable SMPs that employ glassy, photoresponsive polymeric materials, which are capable of rapid optical-fixing with short exposures (&#x3c;&#x3c;5 min) of eye-safe visible light. Key to the optical fixing is the use of polymeric materials composed of covalently attached photochromic units such as azobenzene and the use of light capable of inducing simultaneous trans-cis and cis-trans isomerization of azobenzene or other photochromic moieties capable of similar cycling. Upon exposure to light in this wavelength regime (440-514 nm for the azobenzene unit here), real and lasting reconfigurations are induced capable of fixing both the optically induced strain as well as mechanically induced strain. A linear dependence of bending angle on polarization angle is observed and may be used to control the shape reconfiguration of the SMPs.

Optically fixable shape memory polymers

A new class of phototropic liquid crystal mixture comprises a liquid crystal host and one or more photodichroic dyes, wherein exposure of the mixture to an activating light causes a light-induced increase in order parameter of the mixture. In some examples, in the absence of the activating light, the phototropic mixture has a lower order parameter than the liquid crystal host, while in the presence of activating light, the phototropic mixture has a higher order parameter than the liquid crystal host. In some examples, upon exposure to the activating light, the phototropic mixture undergoes a phase transition from a material with a lower order to a material with higher liquid crystalline order. In some examples, activating light causes the mixture to transition from an isotropic phase to a nematic phase, from an isotropic phase to a cholesteric phase or form a nematic phase to a smectic phase.

Phototropic liquid crystal material and processes

Compositions of azobenzene-containing, photomechanically active, copoly(amic acids) and linear copolyimides comprising an azobenzenediamine, a rigid dianhydride, and a flexible dianhydride; and methods of making the same.

Cross-linked polyimides based on a novel crosslinker and methods of making the same. The general structure of these heat-resistant and amorphous polyimides is shown as follows: in which n, m, and l denote the degrees of polymerization (DP) of each arm and the linking group R' is one of the following moieties: &#x2014;C(CF)&#x2014;, &#x2014;O&#x2014;, &#x2014;SO&#x2014;, &#x3e;C(&#x2550;O), &#x2014;OPh-C(CH)-PhO-, -(Ph)C(CF)&#x2014;, or a direct bond (&#x2014;). Films (cantilevers) comprising cross-linked polyimides according to the present invention demonstrate photodirected bending upon exposure to linearly polarized light.

Growing community of inventors

Centerville, OH, United States of America

Timothy J White