Thermal circuit incorporated into liquid crystal elastomer

Abstract

The present invention provides a liquid crystal elastomer composition having a liquid crystal elastomer body configured to include a thermal circuit that connects a heat source to a heat sink via a plurality of first thermal paths from the heat source through the liquid crystal elastomer body to the heat sink. [Solution] Liquid crystal polymers and liquid crystal elastomers are provided herein that are configured to include a thermal circuit for creating thermal paths between various nodes of a thermal circuit, including a heat source 120, a heat sink 130, and an insulated area or insulated body 160. The liquid crystal elastomers described herein can be configured to include portions of the thermal circuit having a modified conductivity that satisfies specifications for heat flow along the thermal path and temperature of nodes within the thermal circuit. The liquid crystal elastomers described herein include a modifiable thermal conductivity based on a selected alignment of the director of the liquid crystal elastomer.

Description

Technical Field

[0001] Cross - Reference to Related Applications This patent application claims the priority of U.S. Provisional Patent Application No. 63 / 138,788, filed on January 18, 2021, and incorporates its entire disclosure by reference.

[0002] This disclosure generally relates to liquid crystal elastomers (LCEs), and more specifically, but not limited to, to thermal circuits incorporated into LCEs.

Background Art

[0003] This section provides background information to facilitate a better understanding of various aspects of the present disclosure. It should be understood that the description of this section of this document should be read from this perspective and should not be read as an admission of prior art.

[0004] Generally, polymers and elastomers are isotropic and good thermal insulators. Polymers and elastomers can be used as thermal insulators for high - sensitivity electronic devices. These materials have been used in electronic devices and other systems, but pose various problems due to their inherent thermal insulation properties. For example, current methods and designs for modulating and controlling the thermal conductivity of a thermal path through a polymer body or a liquid crystal elastomer body remain limited. Further, current methods generally rely on adding composite materials to a polymer or elastomer matrix to adjust the thermal conductivity, which can impede overall performance and increase costs.

Summary of the Invention

[0005] This summary is provided to introduce a selection of concepts that are further described below in the detailed description. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in limiting the scope of the claimed subject matter.

[0006] In one embodiment, the disclosure relates to a liquid crystal elastomer composition having a liquid crystal elastomer body configured to include a thermal circuit connecting a heat source to a heat sink via a plurality of first thermal paths from the heat source through the liquid crystal elastomer body to a heat sink. In some embodiments, the plurality of first thermal paths include a shortest first thermal path configured to align with more than a first majority of directors along the shortest first thermal path. In some embodiments, the thermal circuit of the liquid crystal elastomer body is further configured to connect the heat source to the insulated body via a plurality of second thermal paths from the heat source through the liquid crystal elastomer body to an insulated body. In some embodiments, the plurality of second thermal paths include second thermal paths configured to be orthogonal to more than a second majority of directors along the shortest second thermal path. In some embodiments, the thermal circuit of the liquid crystal elastomer body is further configured to connect the insulated body to a heat sink via a plurality of third thermal paths from the insulated body through the liquid crystal elastomer body to a heat sink. In some embodiments, the multiple second heat paths include a shortest third heat path configured to be more orthogonal to the third majority of directors along the shortest third heat path.

[0007] In additional embodiments, the disclosure relates to a liquid crystal elastomer composition having a liquid crystal elastomer configured to include a thermal circuit having a portion of the liquid crystal elastomer that is insulated from a node contact surface. In some embodiments, the portion of the insulated from a node contact surface includes a director configured to be aligned parallel to the contact surface edge of the portion of the insulated from a node contact surface.

[0008] In further embodiments, the disclosure relates to a method for creating a liquid crystal elastomer having a heat sink contact surface edge perpendicular to the director orientation of the liquid crystal elastomer. Generally, the method involves extruding a portion of liquid crystal ink through a nozzle. In some embodiments, the extrusion thereby applies a shear force to the liquid crystal ink, i.e., (1) sufficient to align the director orientation of the liquid crystal ink by the shear force, and (2) oriented perpendicular to the heat sink contact surface edge of the liquid crystal elastomer. In some embodiments, the method further includes crosslinking the extruded portion of the liquid crystal ink with a portion of the liquid crystal elastomer having a director orientation by illuminating the extruded portion of the liquid crystal ink with ultraviolet light after the liquid crystal ink has exited the nozzle.

[0009] In additional embodiments, the disclosure relates to a method for creating a liquid crystal polymer having a heat sink contact edge perpendicular to the director orientation of the liquid crystal polymer. Generally, the method includes: placing a liquid crystal mesogen mixture prepared in a non-stoichiometric ratio of functional groups for a Michael addition reaction in contact with a heat sink contact surface; reacting the liquid crystal mesogen mixture while it is in contact with the heat sink contact surface until the reaction stops due to the non-stoichiometric ratio, thereby creating an intermediate liquid crystal polymer having an excess of unreacted functional groups including a heat sink contact edge in contact with the heat sink contact surface; straining the liquid crystal polymer away from the heat sink contact edge; and exposing the intermediate liquid crystal polymer having an excess of unreacted functional groups to a crosslinking stimulus configured to react the excess of unreacted functional groups, thereby creating a liquid crystal polymer having a heat sink contact edge.

[0010] In another embodiment, the present disclosure relates to a method for creating a liquid crystal polymer having a director orientation of the liquid crystal polymer and an aligned thermal insulation contact edge. Generally, the method includes: placing a liquid crystal mesogen mixture prepared in a non-stoichiometric ratio of functional groups for a Michael addition reaction in contact with a thermal insulation contact surface; reacting the liquid crystal mesogen mixture while it is in contact with the thermal insulation contact surface until the reaction stops due to the non-stoichiometric ratio, thereby creating an intermediate liquid crystal polymer having an excess of unreacted functional groups including a thermal insulation contact edge in contact with the thermal insulation contact surface; straining the liquid crystal polymer in a direction parallel to the thermal insulation contact edge; and exposing the intermediate liquid crystal polymer having an excess of unreacted functional groups to a crosslinking stimulus configured to react the excess of unreacted functional groups, thereby creating a liquid crystal polymer having a thermal insulation contact edge.

[0011] In further embodiments, the disclosure relates to a method for creating a liquid crystal polymer having a heat sink contact edge perpendicular to the director orientation of the liquid crystal polymer. Generally, the method includes applying an anchoring agent to a heat sink contact surface; placing a liquid crystal mesogen mixture prepared in a non-stoichiometric ratio of functional groups for a Michael addition reaction in contact with the heat sink contact surface; reacting the liquid crystal mesogen mixture while it is in contact with the heat sink contact surface until the reaction stops due to the non-stoichiometric ratio, thereby creating an intermediate liquid crystal polymer having an excess of unreacted functional groups, including a heat sink contact edge in contact with the heat sink contact surface; and exposing the intermediate liquid crystal polymer having an excess of unreacted functional groups to a crosslinking stimulus configured to react a population of excess unreacted functional groups, thereby creating a liquid crystal polymer having a heat sink contact edge.

[0012] A more complete understanding of the subject matter of this disclosure can be obtained by referring to the following detailed description in conjunction with the attached drawings. [Brief explanation of the drawing]

[0013] [Figure 1] The layout of a liquid crystal elastomer (LCE) body prepared as described herein, including a thermal circuit between a heat source, an insulated body, and a heat sink, is shown. [Figure 2A] This shows an embodiment of thermal anisotropy created by controlling the orientation of a portion of the director of the LCE along the thermal path. Figure 2A shows Kz > Kx = Ky. [Figure 2B] Various configurations of LCE are shown. Polydomain configurations are demonstrated by mesogens that form randomly oriented liquid crystal domains without global alignment. Conversely, the mesogens of monodomain LCE are oriented along the director. [Figure 2C] The thermal conductivity and temperature plots for monodomain LCE (parallel), monodomain LCE (perpendicular), and polydomain LCE, measured in two orthogonal directions, are shown. [Figure 3] This document presents a heat transfer specification, including common terminology used to describe heat transfer, and the resulting thermal circuits. [Figure 4] A flowchart of the method for preparing the LCE composition described herein is shown. [Figure 5] This shows an embodiment of a thermal circuit incorporated into an LCE configured for use in embodiments where the heat source is closer to the heat sink than to the insulated body. [Figure 6] This shows an embodiment of a thermal circuit incorporated into an LCE body, configured for use in embodiments where the heat source is positioned at a distance from the heat sink similar to the distance to the insulated body or insulated area. [Figure 7] This shows an embodiment of a thermal circuit incorporated into an LCE configured for use in an embodiment where the insulated body is positioned between a heat source and a heat sink. [Figure 8] A flowchart of the method for producing the liquid crystal polymer (LCP) described herein is shown. [Figure 9] A flowchart of the surface anchoring method described herein is shown. [Modes for carrying out the invention]

[0014] The following descriptions and drawings are illustrative and should not be construed as limitations. Numerous specific details are provided to provide a full understanding. However, in some cases, well-known or conventional details are omitted to avoid obscuring the description. References to one embodiment or embodiment in this disclosure do not necessarily refer to the same embodiment, and such references mean at least one. References to “one embodiment” or “embodiment” in this specification mean that certain features, polymer compositions, design structures, or properties described in relation to an embodiment are included in at least one embodiment of this disclosure. Occurrences of phrases such as “in one embodiment” in various parts of this specification do not necessarily all refer to the same embodiment, nor do they refer to separate or alternative embodiments that are mutually exclusive with other embodiments. Furthermore, various features that may be shown by some embodiments rather than other embodiments are described.

[0015] Methods and designs for modulating and controlling the thermal conductivity of multiple thermal paths through a liquid crystal polymer (LCP) or liquid crystal elastomer (LCE) body that creates a thermal circuit internally are described herein. As described herein, an LCE is used as a specific embodiment of an LCP, which may include an incompletely crosslinked network, such as an excess of unreacted functional groups in the LCP. For example, as described herein, an LCP having controlled conductivity may include a reduction in thermal conductivity between the insulated body and a heat source or heat sink designed to transfer or receive heat through a thermal circuit. As further described herein, an LCE body is designed to facilitate heat transfer along a thermal path between a heat source and a heat sink by modulating the thermal conductivity along these various thermal paths, while limiting heat transfer to the insulated body through the thermal circuit (for example, to limit the heat received from the heat source and / or heat transferred to the heat sink).

[0016] Embodiments are described herein that have longer thermal paths with higher conductivity than shorter thermal paths by creating a specific arrangement of directors within the LCE material. Furthermore, embodiments are described herein that have higher conductivity thermal paths adjacent to thermal paths with low conductivity or relatively low conductivity. Furthermore, embodiments are described herein that have mapped thermal paths through an LCE body created by a novel arrangement of directors such that each portion creates these thermal paths with directional anisotropy of thermal conductivity.

[0017] Figure 1 shows a layout of an LCE body 110 prepared as described herein to include a thermal circuit between a heat source 120, an insulated body 160, and a heat sink 130. In one embodiment, the heat source 120 is packaged inside the LCE body 110 including the thermal circuit, and the heat source may be a light-emitting diode (LED) chip packaging having specific requirements for permeability through the LCE and / or low distortion transmission of light on specific sides of the LCE body. For example, the bottom of the LCE may be a particularly important light output direction, and therefore the bottom side of the LCE packaging must be particularly permeable and / or have low optical distortion or optical dispersion. In some embodiments of the heat source 120, the heat source must be highly sensitive to heat generation and also have a specific heat outflow to maintain the correct operating temperature of the heat source 120. One such example is an LED chip packaging that may overheat if there is no specific heat flow from the heat source 120 to the heat sink 130. These and other boundary requirements may define the design of the thermal circuit within the LCE body 110.

[0018] This embodiment shows a thermal circuit design having a heat source 120, such as an LED package inside the LCE body 110, that covers the heat source 120. The thermal circuit can be defined by equivalent heat resistors 150, 152, 154, 156 between the heat source 120 and the heat sink node contact surface 132, and between the heat source 120 and three different edges of the thermal insulation material node contact surface 162, respectively. As further described herein, portions of the LCE 110 can include portions that are more transmissive or have lower optical distortion than other portions of the LCE. The equivalent heat resistors 152, 154, 156 are each connected to the environment 160 surrounding the LCE. In one embodiment, the requirement to maintain high heat resistances 152, 154, 156 and low heat flow from the heat source 120 through the contact surface 162 to the environment 160 means that the heat resistance 150 should be maintained low to facilitate heat flow from the heat source 120 through the contact surface 132 to the heat sink 130. According to some embodiments described herein, heat flow can be directed through many equivalent heat resistances by the selection of LCE director alignment for many of the important heat paths between nodes on the thermal circuit.

[0019] The physical boundary requirements of the LCE can include, for example, that the LCE should satisfy all of the space between the heat source 120 and the heat sink 130, as well as a defined outer envelope 162 that functions as a contact surface with the external environment 160 (e.g., air). In the embodiment shown herein, the boundary contact surface 162 with the external environment 160 receives only low heat flow, and thus this embodiment has the requirement of treating the environment 160 as a heat-insulated body and the contact surface 162 as a heat-insulated node contact surface edge. In the example where the heat source 120 is an LED light source, the requirement that the contact surface 162 does not receive heat flow can be based on the optical requirement that the contact surface remains undistorted over the operating temperature range, operating power dissipation range, or operating output range of the heat source 120.

[0020] Therefore, the thermal path is designed within the thermal circuit of the LCE such that it is generally represented by thermal resistors 150, 152, 154, 156 that represent the respective resistances to the heat flow between the heat source 120, the heat sink 130, and the thermally insulated body 160 (or area / environment). These different thermal resistances can be matched to the operating requirements of the heat source 120, as well as the heat flow requirements of the nodes of the thermal circuit such as the boundary contact surfaces 132, 162, and the heat sink 130. For example, resistor 150 strongly affects the heat flow between the heat source 120 and the heat sink 130 across the contact surface 132, and this heat flow establishes operating parameters that can be maintained by the thermal circuit, such as the operating temperatures of the heat source and the heat sink respectively, and the heat flow through resistor 150 between these two nodes when they are at their operating temperatures. The thermal resistance characteristics of the thermal path between the nodes of the thermal circuit incorporated within the LCE enable a novel configuration of thermal resistance paths that can create low-resistance paths with longer heat path lengths than high-resistance thermal paths. The thermal circuit incorporated within the LCE described herein can vary their thermal properties within their homogeneous LCE material using techniques of selective director alignment within the LCE body to create these different thermal conductivities. The effect of these alignments on the thermal path can be explained in terms of the standard notation of thermal conductivity, which can be compared directly or as its reciprocal as resistivity as shown by the equivalent thermal resistors 150, 152, 154, 156 in FIG. 1.

[0021] Figure 2A shows one embodiment of anisotropy of thermal conductivity (K) created by controlling the orientation of the director of a portion of the LCE body. A method for modulating the LCE to create specific thermal paths with different properties is described herein. The thermal conductivity K is shown in the figure along three directions: Kx along the X-axis, Ky along the Y-axis, and Kz along the Z-axis. These different conductivity values ​​are related to the orientation of the mesogen director of the LCE aligned along the Z-axis, as shown in Figure 2A. Thus, this mesogen director alignment along the Z-axis is orthogonal alignment with respect to the heat flows (and thermal paths) along the X-axis and Y-axis, and parallel alignment with respect to the heat flows along the Z-axis. Modulation of conductivity along thermal paths, as described herein, is created by modulating the director orientation with respect to those heat flows. In this embodiment, a calamistic, i.e., rigid rod-shaped mesogen is used to form a nematic liquid crystal elastomer. In other embodiments, other mesogens, such as disc-shaped, or liquid crystal phases such as smectic may be used.

[0022] For example, a director orientation shown aligned with the Z-axis is parallel to both thermal contact surfaces parallel to the XZ plane and thermal contact surfaces parallel to the YZ plane. This minimizes the thermal conductivity flowing along the X and / or Y axes. A director orientation can be parallel to two coordinate planes and orthogonal to a third coordinate plane. As another example, a thermal contact surface parallel to the XY plane is orthogonal to a director orientation shown aligned with the Z-axis. A thermal contact surface can be any surface connecting the thermal nodes of a thermal circuit to the contact surface portion of the thermal circuit created within the LCE, as described herein. Thus, there can be many contact surface edges contained within any contact surface, and director orientations are further described herein with respect to both the contact surface and the contact surface edges.

[0023] The conductivity exhibited by the LCE in direction Kz is significantly different from the conductivity exhibited in directions Ky and Kx. In one embodiment, comprising an LCE synthesized from a functionalized mesogen of 4-(3-acryloyloxypropyloxy)benzoate 2-methyl-1,4-phenylene ester; 2-methyl-1,4-phenylene-bis[4[3(acryloyloxy)propyloxy]benzoate], the thermal conductivity anisotropy exhibited by the LCE includes a 100% increase in conductivity along the director orientation compared to conductivity orthogonal to the director orientation. Other embodiments of the LCE material may provide greater thermal conductivity anisotropy based on measures of director orientation and director alignment, such as an order parameter of the LCE material ranging from 0 to 1. Different thermal conductivity can be achieved by orthogonal and parallel orientations to the thermal path by creating LCEs with different alignments as described herein. Similarly, intermediate conductivity values ​​can be achieved by orienting the director at a certain angle (e.g., 0–90 degrees) with respect to the thermal path. As further described herein, the different anisotropies exhibited by different LCE materials can affect different patterns of directors in the LCE thermal circuit when their properties are combined with other requirements such as heat flow entering and leaving the node contact surfaces of the LCE.

[0024] As described herein, different complex strains can be applied to the LCP. The different strain rates described herein can create different order parameters for the directors within the LCP. The order parameter of the LCP is a measure of the average director orientation of the liquid crystal molecular axes (e.g., the thermal path being evaluated through the LCP) having a preferred or measured direction. As further described herein, this measurement of the order parameter may also be described herein as a percentage of the directors oriented along the measured direction. The greater the strain, the greater the order parameter with respect to the direction of the strain, and many different percentages of director orientation and order parameters that can be created by using complex and different strains within the LCP are described herein.

[0025] The unit volume of the LCE shown in Figure 2A may represent a unit portion of the thermal path length. As further described herein, these unit lengths can be very short and may include small portions of the LCE body. As further described herein, multiple thermal paths can exist parallel to one another, each capable of transmitting heat through the LCE body between node contact surface edges. The shortest thermal path between node contact surface edges can be designed to be particularly adiabatic or thermally conductive. As described herein, the thermal paths created by the design of the director orientation along the thermal paths through the LCE body may include multiple three-dimensional thermal paths, such as expansions of specific areas, including a thickness dimension. This thickness dimension can be added to the two-dimensional representation of the LCE body shown herein. These embodiments of the LCE shown in the figures include a two-dimensional representation of a three-dimensional LCE body. The description of the two-dimensional figures herein may be understood to include variable thickness, which also affects the thermal resistance of specific thermal paths between nodes in the thermal circuit.

[0026] By creating a specific arrangement of directors within the LCE material, longer thermal paths with higher conductivity are created than shorter thermal paths. Furthermore, thermal paths with higher conductivity are created adjacent to thermal paths with low or relatively low thermal conductivity. In addition, by creating an LCE body with a novel arrangement of directors, thermal circuits through which heat can flow are created, and each part of the LCE body contains a directional portion of the thermal circuit between nodes.

[0027] Figure 2B shows various configurations on the LCE. The polydomain sample does not have global alignment, while the monodomain sample has global alignment of mesogens. The two configurations were then tested for thermal properties, some of which are shown in Figure 2C.

[0028] The tests demonstrated that polydomain LCE samples lacking long-range orientation (i.e., global director) exhibited uniform thermal conductivity in both measured directions. Thermal conductivity remained nearly constant with increasing temperature. Conversely, monodomain samples showed direction dependence. When parallel to the director, thermal conductivity was approximately twice as high as in the perpendicular direction. With increasing temperature, thermal conductivity decreased slightly in both tested directions. This may be because monodomain samples attempt to slightly contract along the director when heated (and slight changes in geometric shape can affect readings). It should be noted that while various methods exist for producing monodomain samples, this property is not inherent to LCE. To induce a monodomain structure, the LCE must be programmed and synthesized in a specific manner; otherwise, a polydomain structure is formed inherently. Therefore, this property is not inherent to materials chemistry; it depends on the method or the orientation of the liquid crystal (or mesogen) during synthesis.

[0029] The thermal conductivity, diffusivity, and / or specific heat per unit volume were measured for (1) LCE monodomains aligned along the width direction (21 mm × 16 mm × 1 mm), (2) LCE monodomains aligned along the length direction (21 mm × 16 mm × 1 mm), and (3) LCE polydomains (21 mm × 16 mm × approximately 1.5 mm). The results for the LCE monodomains are as follows: thermal conductivity parallel to the director orientation = 0.35 W / mK; thermal conductivity perpendicular to the director = 0.18 W / mK; thermal diffusivity parallel to the director orientation = 0.167 mm 2 / sec; Thermal diffusivity perpendicular to director orientation = 0.087 mm 2 / second. The heat transport properties of the LCE polydomain are shown in Table 1 below. TIFF2026082866000002.tif29170

[0030] Furthermore, thermal conductivity, thermal diffusivity, and / or specific heat per unit volume were measured for (1) LCE monodomains (21 mm × 16 mm × 1 mm) aligned along the width direction (i.e., perpendicular to the director), (2) LCE monodomains (21 mm × 16 mm × 1 mm) aligned along the length direction (i.e., parallel to the director), and (3) LCE polydomains (21 mm × 16 mm × approximately 1.5 mm). The heat transport characteristics of the LCE monodomain samples are shown in Table 2 below, and the heat transport characteristics of the LCE polydomain samples are shown in Table 3 below. TIFF2026082866000003.tif37170TIFF2026082866000004.tif32170

[0031] Figure 3 shows a heat transfer specification, including common terminology for describing heat transfer, and the thermal circuit created thereby. Figure 3 shows standard terminology for describing the heat flow (H), which is governed by a thermal conductivity (K) equal to the thickness (t) of the conductor through which heat flows, divided by the product of the area (A) of the conductor (e.g., the area of ​​the contact surface) and the temperature difference (ΔT) between the two contact surfaces. The two contact surfaces represent a unit portion of the thermal circuit estimated for computation and / or operational purposes, which has the ability to handle the heat flow H while maintaining a consistent temperature between the contact surfaces of the node.

[0032] Since any thermal path includes a non-zero cross-sectional area, each thermal path described herein includes a unit area. Therefore, the shortest thermal path includes the relevant unit area of ​​the surrounding LCE body when determining the thermal conductivity of that path. Along the thermal path, this includes the portion of the LCE body that lies within the unit polygon or unit area around the shortest path connecting two nodes of the thermal circuit and associated therewith.

[0033] While the thickness and unit area classically described in heat transfer describe a length scale in meters, embodiments relating to thermal circuits described herein may include thermal paths having much smaller length scales, such as 10 micrometers, 100 micrometers, 1 millimeter, 10 millimeters, and other shorter length scales. Thus, although the thermal paths described herein involve small cross-sectional areas, discussions relating to these cross-sectional areas and actual thermal paths will include the cross-sectional area through which the heat flows, as will be further described and shown herein. Although multiple thermal paths are included in the drawings, individual specific thermal paths may also be described and readily assumed. Thus, the design of a particular director shown in the figures defines different embodiments of thermal paths, including the real-world thickness of the design shown in cross-section. Each description herein relating to the director orientation of an LCE body and their associated thermal paths of thermal circuits created within an LCE body includes a complete and relevant description of embodiments of various common choices of thermal paths created that can be combined between parts of different embodiments of an LCE body.

[0034] Numerous heat paths exist even through small cross-sectional areas in any material, including LCEs. An example is a heat dissipation circuit for a heat source, which is an electronic circuit that needs to diffuse heat from a source with a specific input area and dissipate that heat to a heat sink with another specific area. The length scale of the LCE can be very small, ranging from about 10 micrometers to a few millimeters (e.g., 10 micrometers to 10 millimeters), and the length of the heat path portion may be only one segment of the length scale. Furthermore, the thickness of the LCE can be as thin as 10 or 100 micrometers.

[0035] Despite the very short length scales of these thermal paths, the difference in heat flow achieved by the selectively oriented LCE described herein can create a highly directional thermal circuit and support the maintenance of a desired temperature at the nodes of the circuit. As further described herein, short thermal paths can still be highly thermally resistant due to the insulating properties of the LCE along those short thermal paths. Thus, the unit of measurement for the area of ​​the minimum thermal path can be a small area such as 10 micrometers × 10 micrometers, i.e., 100 square micrometers, for similarly short thermal paths of 10 micrometers or 100 micrometers. In one such embodiment, the LCE body is a thin film of LCE that provides directional thermal insulation and heat flow for a thermal circuit having a heat source, a heat sink, and an area to be insulated.

[0036] Therefore, the length scales of these thermal paths further described herein with respect to director orientation may be very short. Director orientation can be identified using specific measurement techniques, such as polarization probes or X-ray diffraction probes (e.g., wide-angle X-ray scattering, small-angle X-ray scattering). These may include samples of 1 millimeter or more to produce results containing identifiable director orientation from a sample of a portion of an LCP body. Thus, in some embodiments having very small length scales, if the length scale of a single thermal path is too short to identify director orientation along the thermal path using specific techniques for examining director orientation, additional copies of the thermal path can be used to multiply or replicate the effect of the director along the thermal path (e.g., by X-ray diffraction), such as by stacking multiple units of thermal path.

[0037] Embodiments described herein include a definition of a majority director orientation oriented in relation to a specific thermal path, having a majority director orientation such as 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 97%, 99%, and 99.5% directors, measured by measurement techniques including the use of polarization or X-ray diffraction. In some embodiments, the measurement techniques may show other measurement data that can be converted or interpreted as percentages, order parameters, or other measurements of director orientation in the LCE sample described herein. In some embodiments, these majority directors may be defined as having a monodomain along the orientation of that majority director.

[0038] For computational purposes in thermal circuits, a node is considered to have sufficient thermal conduction within the node so that the temperature of the node boundary is consistent across the node contact surface. The node contact surface (e.g., boundary) of a LCE described herein includes the portion of the LCE configured to contact the node at the node contact surface. Therefore, the description of the node contact surface or node contact surface boundary of a thermal circuit incorporated into an LCE does not include the node itself. In some cases, a single physical object can be treated as an ideal thermal node, supplying heat at a single, consistent temperature to all contact surface surfaces of the node body. In other examples, such as when extreme heat transfer can create temperature differences along different points on the node contact surface, a node can be modeled as one or more nodes. For example, a heat sink with sufficient thermal conduction between its parts (e.g., made of a thermally conductive metal) to withstand absorbed heat flow can, under certain conditions, be modeled as having a single temperature contact surface and a single node within a thermal circuit.

[0039] Under other operating conditions, a heatsink may contain more than one node. For example, in response to extreme heat transfer to a portion of the heatsink, the heatsink contact surface may experience a rise in temperature around that portion of the heatsink, causing a temperature increase compared to other parts of the heatsink. In these cases, where heat flow (e.g., heat flow from a heat source, heat flow to the heatsink, heat flow in any direction toward the insulated object) overloads the node requirements for heat flow, multiple nodes may be created, as the overload on their different thermal paths causes temperature changes for distinct parts of the node. In this case, a second node can be created, allowing excess heat flow to enter and exit that portion of the node, and the circuit can be modified to regulate its flow as needed by creating new LCE director orientation and thermal circuits between all nodes.

[0040] Therefore, any number of designs can be fabricated to include any thermal circuit that can be made using resistive materials and any of the boundary constraints described herein, from the thermal circuits incorporated into the LCE described herein, which include a generalized heat source, a generalized heat sink, and a generalized insulated body. In additional embodiments, the LCE described herein may incorporate more complex thermal circuits that include contact surfaces and thermal paths of multiple nodes, incompletely defined nodes or dispersed nodes such as parasitic heat sources or heat sinks, or indirect heat sources such as irradiation absorption.

[0041] In additional embodiments, a thermal circuit incorporated into an LCE may have fewer node contact surfaces, such as having only two nodes, including a heat source node contact surface and a heat sink node contact surface, without defined insulated / insulated area node contact surfaces to protect from heat flow within the thermal circuit. In another embodiment, for example, in embodiments where the heat source is unknown or dispersed within the body of the LCE, the thermal circuit within the LCE may have only two node contact surfaces, including an insulated node contact surface and a heat sink node contact surface. As described herein, many periphery node contact surfaces exist, for example, through air contact around the contact surface edges of the LCE body. As further described herein, these periphery or external environment node contact surfaces may include requirements associated with thermal requirements, including optical transparency and uniform heating requirements.

[0042] In other embodiments, the LCE body may have directors oriented to create only the insulated portion of the LCE adjacent to the node contact surface edges of the LCE body. In alternative embodiments, based on the requirements of the thermal circuit and the anisotropic properties of the LCE material, the directors of the rest of the LCE body between the node contact surfaces may be oriented in a direction that further insulates the node contact surface edges from each other. As an example of an LCE body having insulated node contact surface surfaces, the LCE body may include opposing surfaces (e.g., top and bottom, left and right) necessary to insulate from heat flow passing through the surface and into and out of the rest of the LCE. In this embodiment, portions of the LCE proximal to or adjacent to the node contact surface edges have directors oriented parallel to those contact surface edges. Based on the insulated properties of the LCE, other portions of the LCE body may have directors configured in an insulated orientation relative to these node contact surface edges, or they may be oriented in a different direction for other properties of the LCE.

[0043] Figure 4 shows a flowchart of a method for creating an LCE composition as described herein. Method 400 describes a method for creating a specific arrangement of director orientations within an LCE body by extruding a portion of liquid crystal ink through a nozzle 402, applying a shear force to the liquid crystal ink while extruding the ink through the nozzle 404, thereby controlling the orientation of the directors within the LCE to align with the direction of the shear force. The shear force is sufficient to align the directors of the liquid crystal ink along the direction of the force 404 before the ink is exposed to a crosslinking stimulus, such as light, in embodiments of liquid crystal ink containing a photoinitiator 406. In one embodiment, the crosslinking step 406 is caused by exposing the liquid crystal ink to ultraviolet (UV) light. This exposure may be configured to crosslink the liquid crystal ink to the LCE 406 while the directors are oriented along the direction of the shear force applied by the nozzle when the ink is extruded 402.

[0044] 406 After crosslinking by initiating crosslinking (for example, by exposure to UV light), the method may include a second extrusion step 408 of the second portion of the liquid crystal ink through a nozzle. 408 This second extruded portion of the liquid crystal ink may come into contact with the previously crosslinked first portion of the LCE. 406 After the second portion of the liquid crystal ink has been extruded through the nozzle, 408 the second portion of the liquid crystal ink may be exposed to a crosslinking initiator, such as UV light. 410 If the second portion of the liquid crystal ink is in contact with the first portion of the LCE, in some embodiments, a second illumination is performed to chemically bond the second portion of the liquid crystal ink to the first portion of the LCE. 410 In some embodiments, the first illumination of the first portion of the liquid crystal ink with UV light is adapted to leave unreacted portions of the first portion of the liquid crystal ink. In these embodiments, these unreacted portions of the first portion of the liquid crystal ink allow for additional chemical bonding between the first portion of the LCE and the second portion of the liquid crystal ink by the second illumination step of both with UV light.

[0045] Following the second extrusion step 408 of the liquid crystal ink through the nozzle, a number of subsequent portions of the liquid crystal ink may be extruded, including portions of liquid crystal ink that remain completely uncrosslinked, in order to increase the chemical bonding between different portions of the LCE created by a number of crosslinking steps. Thus, the extrusion step 408 and the chemical bonding step 410 may be repeated over a number of iterative cycles to create larger and more complex LCE bodies. The direction of the shear force applied in the extrusion step each applies a shear force to each portion of the liquid crystal ink and thus controls the orientation of the director in the portions of liquid crystal ink as the liquid crystal ink is extruded through the nozzle. As further described herein, the entire body of the LCE material may be created with individual director orientations applied to the smallest portions of LCE ink available for extrusion through the nozzle 404, 408. The size of these portions of liquid crystal ink and LCE may include very small monodomains of director orientation that may have orientations aligned with or perpendicular to the thermal paths of the LCE, as further described herein. For example, in the embodiments of thermal circuits incorporated into an LCE body shown herein, the director orientation can be controlled over a wide area and gradually constructed by additive manufacturing techniques, such as extruding liquid crystal ink from a nozzle, to control the director on a small length scale controllable by a printing nozzle.

[0046] In some embodiments, the method includes a third illumination step 412 in which the LCE is illuminated with UV light after multiple portions of the liquid crystal ink have been extruded 402, 408 and chemically bonded to one another 410. In many embodiments, the LCE described herein contains a multitude of portions of liquid crystal ink that are chemically bonded to one another. This third illumination step 412 with UV light may be designed as the final cured phase of the entire LCE containing this multitude of portions. The third illumination step 412 may be carried out over the entire LCE for a longer period (e.g., one hour, several hours) at a higher UV light intensity or UV light energy to ensure that any remaining unreacted or non-crosslinked mesogenous population of the LCE is completely crosslinked by the third illumination step.

[0047] Figure 8 shows a flowchart embodiment of method 800 for producing an LCP, which is further described herein. The method comprises step 802 of placing a liquid crystal mesogen mixture in contact with a contact surface molding surface, thereby defining a contact surface edge in the liquid crystal mesogen mixture. The method then reacts the liquid crystal mesogen mixture until the reaction stops due to the non-stoichiometric ratio of functional groups in the mesogen mixture (804), thereby producing an LCP with an excess of unreacted functional groups. The method then deforms the LCP with respect to the contact surface edge in a certain direction (e.g., orthogonal, parallel, or at an oblique angle) 806. The method then exposes the LCP with the excess of unreacted functional groups to a crosslinking stimulus, thereby reacting the unreacted functional groups and producing an LCP with a contact surface edge 808.

[0048] In one embodiment, the 802 liquid crystal mesogen mixture, placed in contact with a contact surface molding surface, is a liquid crystal mesogen mixture containing non-stoichiometric ratios of functional groups (e.g., functional groups with an excess population, thiol functional groups, or excess acrylate functional groups). Such limited reactions can be described by Michael addition reactions. In one embodiment, these functional groups of the mesogen mixture may be thiol groups and electron-deficient groups (e.g., acrylate groups), and the non-stoichiometric ratio may include excess acrylate groups. In this embodiment, the mesogen mixture can be reacted first so that the thiol groups and acrylate groups react until the thiol groups react with the acrylate groups (e.g., after a certain period of time until the reaction is complete), thereby creating an LCP product with additional unreacted functional acrylate groups 804. In other embodiments, other chemistry of liquid crystal mesogen mixtures containing different functional groups, including different secondary crosslinking stimuli, may be used.

[0049] Other Michael addition reactions may be used herein. For example, other ways of creating non-stoichiometric functional groups (e.g., thiol group, acrylate group), including solutions containing a single complex mesogen containing both a thiol functional group and an acrylate functional group, can be used in conjunction with the methods described herein. The reactions described herein have been demonstrated with non-stoichiometric acrylate-to-thiol group ratios greater than 1:1 and less than 2:1. In particular, solutions with a non-stoichiometric ratio of 1.15:1 were used in many of the examples herein.

[0050] Next, method 800 reacts the liquid crystal mesogen mixture until the Michael addition reaction is stopped because all or almost all of one of the stoichiometrically matched functional groups in the mixture has reacted, thereby creating an LCP product having some unreacted functional groups 804. For example, step 804, in which the liquid crystal mesogen mixture is reacted in contact with the contact surface molding surface, (e.g., pressed against it) and creates a contact surface (e.g., including the contact edge) of an LCP product having excess unreacted functional groups.

[0051] In one embodiment, the contact surface is a solid surface. In other embodiments, the contact surface may be a flexible surface such as a flexible bladder or a fluid (e.g., air). In one embodiment, pressure (e.g., force, stress) is maintained between the contact surface and the mesogen mixture while the mesogen mixture is reacting in order to maintain contact with the molded surface.

[0052] In one embodiment, the LCP compound having unreacted functional groups remains in contact with the contact surface molding after the first step of the Michael addition reaction (e.g., after the completion of the first reacting step 804). In another embodiment, the LCP compound may be removed from contact with the contact surface molding after the completion of the reacting step 804.

[0053] Next, method 800 strains the liquid polymer body with respect to the contact surface edge 806. An LCP having excess unreacted functional groups can be strained so that the director orientation of the polymer aligns with the direction of the strain 806. Subsequently, while maintaining the strain (e.g., with the same strain, with a different strain), the unreacted functional groups may be exposed to a crosslinking stimulus 808 to fix and lock the director orientation in that direction. This newly locked orientation of the director can be expressed as shape fixation in the LCP as described herein.

[0054] For example, the macroscopic characteristic of shape fixation is another measure (e.g., a percentage) of the fixed director orientation created by the exposure 808 process (e.g., the bridging process). Shape fixation can be defined as the ratio of fixed strain to applied strain. Fixed strain remains after the exposure 808 process and after the release of strain from the LCP (e.g., removing the LCP from the straining apparatus). The applied strain used in the calculation is the constant strain applied during the straining 806 process. In some embodiments, the applied strain used in the calculation is the average or midpoint of the applied strain. In other embodiments, the applied strain is the maximum strain applied during the straining 806 process.

[0055] Shape retention after exposure can reach 90%, 95%, or more, for example, if the LCP retains a strain of 270% or more after the release of a straining device that forces a constant 300% strain (e.g., removing the LCP from the fixture). As further described herein, the LCP herein may have strain aligned in multiple directions and / or multiple strain rates around the node contact surface edges and also throughout the LCP body. Thus, shape retention after these strains must be considered when sizing the initial workpieces 804 of the node contact surface of the LCP body before straining 806, since the node contact surface retains most of the strain applied by the method.

[0056] The strains 806 provided herein are described as being perpendicular, parallel, and oblique to the contact surface edges with the nodes of the thermal circuit. As further described herein, the conductivity of the LCP is maximum for heat flows in a direction along or parallel to the director orientation, while the conductivity is minimum for heat flows in a direction perpendicular to the director orientation. Furthermore, there is an intermediate conductivity for heat flows at an oblique angle to the director orientation (e.g., between the direction perpendicular to the director orientation and the direction parallel to it).

[0057] To create complex thermal circuits through the LCP, multidirectional strains can be applied to different parts of the LCP, including complex maps of director orientations as further described herein (806). Similarly, thermal circuit node contact surfaces (e.g., heat sink contact surfaces, insulation contact surfaces, heat source contact surfaces) may have node contact surfaces of complex shapes and therefore require complex apparatus or fixtures to maintain the 806 process of straining the LCP. In some embodiments, the 806 process of straining the LCP continues throughout the entire 808 process of exposing the LCP to a bridging stimulus. In other embodiments, the straining 806 process may be released before the completion of the exposure 808 process. In yet another embodiment, the straining 806 process may include applying different levels of strain and / or different stresses during the exposure 808 process.

[0058] The complex strains and shapes of the node contact surfaces required in different embodiments of this specification can be created using appropriately designed fixtures or stretching devices. In alternative embodiments, as further described herein, the LCP can be distorted with complex strains to create complex patterns of director orientation (806). For example, certain thermal circuit nodes having circular or curved contact surface surfaces are shown herein, and these curved surfaces may require a curved fixture or curved stretching device to apply strain in a specific direction relative to the node contact surface edge. For example, a circular node contact surface can be distorted circumferentially by being pressed against a device that expands the circumference (e.g., distorted around the circumference of a curved contact surface edge). The shapes of the contact surface edges described herein may be regular or irregular. For example, a conical device can be used to expand the circumference of a circular node contact surface, thereby distorting the LCP tangentially to the circle at each point and therefore parallel to the contact surface edge (e.g., creating an adiabatic node contact surface).

[0059] Complex stretching equipment can create different strains (e.g., different amounts, different directions) along the contact surface edge. As an example, the heat source 702 node contact surface edge shown in Figure 7 can create different strain concentrations around the circumferential portion of the contact surface edge, depending on the equipment used to strain the LCP portion of the heat source node contact surface. As another example, a thin film having two wide surfaces and a small height dimension can be stretched in one or more directions along the surface of the film (e.g., perpendicular to the height dimension of the thin film), thus creating a director orientation parallel to the surface of the film, which can also function as a thermal insulation contact surface node contact surface.

[0060] In alternative embodiments, the LCP can be deformed in a direction away from the contact surface edge to create a director orientation perpendicular to the contact surface edge (806). In some embodiments, as further described herein, directions at angles other than perpendicular or parallel to the thermal circuit node contact surface edge can be used to create different conductivity adjacent to that contact surface edge.

[0061] In some embodiments, a device or jig for straining the LCP can be attached to a mounting support portion of the LCP body. This mounting support portion can be used for the straining 806 process (e.g., transmitting strain and equalizing the strain along the contact surface edge) and may be intended to be removed after the straining 806 process is no longer required. For example, a thin film may have a mounting support portion that allows the thin film to be strained along its thin dimensions using a mounting support portion attached to its thin dimensions for processing, and the mounting support portion is later removed (e.g., after the straining 806 process is completed and the straining process is reduced). As another example, before segmenting a large LCP thin film into many smaller thin films, a larger LCP thin film portion with an excess of unreacted functional groups can be created (804), strained (806), and exposed to crosslinking stimuli (808). In this embodiment, many of these thin films serve as mounting support portions for other smaller thin films. The mounting portion can be modified to create different strain concentrations, including increased strain concentration or equalization of strain near the contact surface edge of the LCP, based on the 806 straining process.

[0062] Method 800 then exposes the LCP having an excess of unreacted functional groups to a crosslinking stimulus configured to react the excess of unreacted functional groups in the LCP 808. As further described herein, this exposure 808 and the resulting crosslinking create fixation to the director orientation. In some embodiments, step 808 of partially exposing the LCP having an excess of unreacted functional groups results in both partial crosslinking of the excess of unreacted functional groups and partial shape fixation of the resulting LCP. The lack of shape fixation of the unreacted functional groups in a portion of the LCP affects the order parameter of that portion and its conductivity, potentially creating an intermediate value between maximum and minimum conductivity. In one embodiment, the crosslinking stimulus described herein includes exposing the LCP to UV light to react the excess of unreacted functional groups. In one embodiment, the crosslinking initiator is contained in a mesogenic mixture to react the unreacted functional groups.

[0063] Different embodiments of the Michael addition reaction and mesogen mixtures may include different crosslinking initiators to complete the Michael addition reaction and fix the director orientation while aligning with the applied strain 806. For example, in the case of a thiol-acrylate mesogen mixture containing excess acrylate, a crosslinking photoinitiator can be used to react any unreacted acrylate functional groups remaining in the LCP. The thiol-acrylate chemistry described herein is just one example of the many potential liquid crystal mesogen mixtures in which the Michael addition reaction described herein can be used to create a complex map of the director orientation within the LCP.

[0064] In various embodiments, thin layers of LCE and / or LCP can be used to create flexible electronic devices (e.g., thermal circuits, flexible displays). In such embodiments, the bending strain of the thin film is inherently low, so the effect of the bending strain of the thin film on the overall director orientation is very small. In some embodiments, the flexible electronic device is a display, and the LCE and / or LCP material is transparent. In other embodiments, the flexible electronic device is a thermal circuit.

[0065] Figure 9 shows a method 900 relating to surface anchoring according to an aspect of the present disclosure. Method 900 begins with step 902 of applying an anchoring agent to a molded surface. In some embodiments, the anchoring agent is homeotropic to create an alignment perpendicular to the mold surface. In some embodiments, the anchoring agent is flat to create an alignment parallel to the mold surface. In some embodiments, the anchoring agent is polyimide or polyamide. Following the application of the anchoring agent 902, a liquid crystal mesogen mixture is brought into contact with the molded surface and positioned 904. The mesogen mixture is given time to align with the anchoring agent 906. Following steps 904 and 906 of bringing the liquid crystal mesogen mixture into contact with the molded surface, the mixture is exposed to UV light for curing 908. In some embodiments, the flat anchoring agent is rubbed with felt to induce a director profile of the thermal circuit.

[0066] Figure 5 shows one embodiment of a thermal circuit incorporated into an LCE, configured for use in embodiments where the heat source is closer to the heat sink than to the insulated body. The LCE body 510 is an enclosure for a heat source 520, which in some embodiments may be a solid element such as an LED or a light source. For example, the solid element may be a microprocessor or integrated circuit isolated on the rest of the electronic circuit board and seated in thermal contact with the heat sink, and the electronic circuit board may include a heat-sensitive device and therefore an insulated body node or insulated area node in the thermal circuit.

[0067] The LCE body 510 provides director orientation within the LCE for several different parts of the thermal circuit, as well as for effective heat paths from the heat source 520 through the LCE body 510 to various contact surfaces with the environment, such as the contact surface 540 with the heat sink 530 and the main window contact surface 548 with the external environment, such as air or another fluid. In one embodiment, the heat source 520 may be an LED, and the main window contact surface 548 may be a relatively transparent and distortion-free opening from which irradiation from the LED can exit.

[0068] This embodiment, which shows a thermal circuit incorporated into the LCE, includes a parallel director orientation of the LCE along three adjacent portions of the heat source contact surface edges 524, 526, and 528. In the illustrated embodiment, the director orientation parallel to the contact surface edges remains uninterrupted along the shortest thermal path between the heat source 520 and the portions of the LCE contact surface with the external environment, such as the contact surface portions 544, 548. In one embodiment, the parallel director orientation forms as a monodomain within the LCE, creating relative permeability or transparency through the portions of the LCE contact surface with the external environment, including the contact surface portions 544, 548.

[0069] In the illustrated embodiment, the director orientation of the LCE body 510 adjacent to the contact surface edges 524, 526, and 528 is parallel to those contact surface edges, thereby creating a high thermal resistivity portion of the LCE around the heat source 520. This additional insulation around the three sides 524, 526, and 528 of the heat source requires a larger heat flow transport requirement, which is carried by the heat path between the contact surface edge 522 with the heat source 520 and the contact surface edge 540 with the heat sink 530. However, in this embodiment, this configuration with reduced heat transport capacity is chosen to create a larger area of ​​light transmittance and transparency through the LCE body 510 for some portions of the LCE body 510 configured to transmit light from the heat source to the external environment.

[0070] The thermal path of the LCE body 510 between the contact surface edge 522 with the heat source 520 and the contact surface edge 540 with the heat sink 530 is designed to have a director oriented substantially perpendicular to the contact surface edge 522 with the heat source, and in this embodiment designed for the thermal diffusion portion of the LCE body 510, it has an angle of deviation from perpendicular. In these thermal diffusion regions, the director is deviated by a small angle from perpendicular to diffuse heat and to fit between the contact surfaces 522 and 540 of different lengths. These thermal diffusion portions of the thermal circuit fit the length difference between the upper contact surface edge 522 with the heat source through the LCE body 510, and the director creates a conductive thermal path that diffuses heat over the longer length of the contact surface 540 with the heat sink 530. Thermal diffusion through these diffusive thermal paths can be achieved by diffusing in one or more dimensions, as necessary, for each portion of the respective contact surfaces 522, 540.

[0071] The degree of deviation from orthogonality with respect to the contact surface 522 may be determined by the requirements of the heat source 520 node in the thermal circuit and other requirements of the LCE body 510. As further described herein, other requirements of the LCE, such as transparency and / or permeability of the LCE, can further refine the selection of orthogonal directors in particular portions of the LCE body 510. Thus, in some other embodiments, other portions of the LCE body 510 may have all or substantially all of their directors aligned to create transparency in those portions, as in the embodiments described herein for portions of the LCE between the contact surface 528 with the heat source and the main window contact surface 548 between the LCE body 510 and the external environment. For example, in one embodiment, to increase transparency through portions of the LCE adjacent to the contact surface portion 542, the LCE may eliminate some or all of the director orientation shift in portions of the LCE body 510 along the contact surface edge 522 and in portions of the LCE body 510 between the heat source 520 and the heat sink 530. In some embodiments, the monodomains may be formed from directors adjacent to the contact surface edge of the node contact surface of the LCE body 510, such as monodomains aligned with the contact surface edge or monodomains aligned perpendicularly to the contact surface edge.

[0072] In the embodiments of the thermal circuits described herein, other boundary conditions of the LCE and the thermal circuit may also be considered. For example, the equal length of the shortest thermal paths between the heat source contact surfaces 524, 526, 528 and the LCE contact surface portions 544, 548 is an effect of these contact surfaces being parallel, and these are shown only as one embodiment. Actual contact surfaces can present an array of thermal path lengths, including a single shortest thermal path between contact surfaces, as shown in further examples of nodal contact surfaces, and thermal paths of different lengths. As another example of a boundary condition, the LCE body 510 may need to fill the physical space between the insulated body and the heat source and / or heat sink (e.g., to provide physical support without gaps). As another example of a boundary condition affecting the thermal circuit, it is possible to embed a limited amount of LCE between the heat source and the heat sink, and therefore require additional conductive thermal paths and detour thermal paths through the thermal circuit described with respect to different embodiments herein. Other boundary conditions may include an insulated body placed between the heat sink and the heat source, or an insulated body whose heat path through the LCE to the heat sink and heat source is shorter than the heat path between the heat sink and the heat source through the LCE. Many potential requirements and design parameters for designing the thermal circuit and LCE body to satisfy both the thermal conduction requirements and other physical requirements of the thermal circuit incorporated in the LCE are described herein.

[0073] The portion of the LCE body 510 that is in contact with the external environment (e.g., air, another fluid) includes certain portions that may have requirements separate from thermal requirements (e.g., transparency based on director orientation) or requirements related to thermal requirements (e.g., transparency regarding relatively little thermal distortion). The main window LCE contact surface portion 548 is shown as a portion of the LCE contact surface with the external environment, extending over a portion of the LCE aligned to be relatively permeable from the heat source contact surface 528 through the LCE to the contact surface portion 548. In the illustrated embodiment, the parallel alignment of the directors in the portion of the LCE adjacent to the main LCE contact surface 548 and the side window 544 ultimately reduces heat dissipation away from the heat source (e.g., through contact surfaces 524, 526, 528) at the expense of improved transparency of the window portion, thereby relating some of the design requirements of this LCE body 510.

[0074] The LCE body 510 shows corner contact surface portions 546 of the contact surface between the LCE and the external environment. In the illustrated embodiment, there may be additional requirements for heat flow between the heat source and the corner portions 546 of the contact surface, and even if there is no requirement for optical transparency on these contact surfaces 546, they may remain insulated to satisfy a continuous low heat flow requirement. For example, the optical path through the contact surface 546 to the heat source through the LCE may include multiple director orientations and therefore may lack relative transmittance to the rest of the LCE. In one embodiment, for example, the LCE packaging is designed to prevent heat buildup or thermal warping, so the corner contact surface 546 must still receive only low heat flow from the heat source, and therefore the portion of the LCE between the heat source 520 and the contact surface 546 must still be an insulated node contact surface. Therefore, despite the lack of optical transparency of the LCE body beneath these contact surfaces 546, the contact surfaces themselves can still be insulated based on the tangential orientation of the director irradiating the contact surfaces 546 from the corners of the heat source contact surface edges 524, 526, 528.

[0075] Some embodiments of LCE bodies 510 and other LCE bodies shown herein include a considerable thickness dimension, which allows for the selection of a director, as well as the discussion herein of in-plane thermal paths. Many of the drawings showing mesogenic orientation herein include only one plane, and the description should be understood to include the three-dimensional nature of thermal paths having a non-zero cross-sectional area. Thermal paths can also travel within three dimensions, and the shortest thermal path can be measured as a path traversing three dimensions.

[0076] Figure 6 shows an embodiment of a thermal circuit incorporated into an LCE body configured for use in an embodiment where the heat source 602 is located at a distance from the heat sink 604 similar to the distance to the insulated body or insulated area 606. Each node is shown along with the shortest thermal paths 608, 610, 612 through the LCE between the nodes.

[0077] Director orientations around these shortest paths often define the dominant heat conduction path (e.g., the one that conducts the most heat) based on the dominance of the heat flow equation and form factor elements (e.g., path length and area). However, the shortest heat path may not be the dominant heat conduction path due to the conductivity along that path being controlled and modulated by the director orientation. These heat paths are further described herein based on how their conductivity is tuned by the director orientation to control which path is the dominant heat conduction path and to utilize longer paths for the conduction of the dominant heat flow.

[0078] The LCE body includes a complex thermal circuit that balances the heat flow from the nodes based on conductivity and length, while also satisfying specific boundary requirements, including the heat flow requirements of nodes 602, 604, and 606. Additional requirements for the LCE body include the physical requirements of the LCE body boundary 620, and the requirement that the LCE fills the volume between the node contact surfaces 602, 604, and 606 (e.g., no gaps for insulation). While there are many heat paths between each of the nodes, for the sake of brevity, only the orientation of the director along the shortest heat path 608, 610, and 612 will be described in detail. Other orientations of the director to create other heat paths can be inferred from these descriptions, as shown in the figures and further described herein. In some cases, as further described herein, heat paths are redundant or dominated by other paths, so little or no heat flow occurs. In these dominant paths with no significant heat flow, there are no thermal requirements for the LCE body, and other non-thermal requirements may determine the LCE design of that part.

[0079] In one embodiment, the shortest heat path 608 is a straight line. As described herein, the shortest heat path through an LCE body is a shortest heat path that includes the surrounding cross-sectional area which may be depicted together with the shortest heat path through the LCE body. Thus, in one embodiment, the shortest heat path is a curved path which includes the cross-sectional area for heat conduction along the path. For example, the shortest heat path can be a curved path if there is a boundary constraint that limits the ability of the shortest heat path to be a straight line and causes the shortest path to follow a curved path through an LCE body between two nodes (e.g., the edge of the LCE body). Alternative heat paths may add to the heat transport capacity of the heat circuit between nodes, but the shortest heat paths 608, 610, 612 between those nodes are described herein for the purpose of describing the orientation of the director along those shortest heat paths. These paths are particularly important because they are likely to be candidates for the dominant heat path of the heat flow between nodes and therefore can significantly affect the operation of the nodes by adjusting the thermal conductivity.

[0080] As further described herein, various thermal requirements of the node (e.g., heat flow, operating temperature) may affect different embodiments of director alignment along the shortest thermal path. For example, these thermal requirements, such as those further described herein regarding node heat flow, may affect the decision of whether to include a portion of the LCE having directors parallel to the shortest thermal path at the node contact surface, or to include only directors perpendicular to the shortest thermal path (and tangential to the node contact surface). Thus, several alternative embodiments herein include descriptions based on the group of directors aligned along those portions of the path or the degree of director alignment. Furthermore, director orientation may be described in relation only to portions of the thermal path adjacent to the contact surface, and / or portions of the thermal path closer to or further away from the node contact surface.

[0081] An LCE body along the shortest thermal path 608 between heat sources 602 within the heat source sink 604 creates a dominant thermal path through the LCE body configured with a director orientation that results in high conductivity along the path. In one embodiment, the director orientation results in high conductivity along the entire thermal path from the contact surface edge with the heat source 602 to the contact surface edge with the heat sink 604. In some embodiments, the director orientation along the shortest thermal path 608 between heat sources 602 within the heat sink 604 may include a single domain or multiple portions of a single domain of director aligned along the shortest thermal path.

[0082] The LCE body along the shortest thermal path 610 between the heat source 602 and the insulated area 606 includes a majority of director orientations perpendicular to the shortest thermal path, thereby creating a highly insulating thermal path. However, as further described herein, along the thermal path, specifically in the portion of the LCE adjacent to the contact surface edge of the heat source 602, there is a portion of the shortest thermal path 610 that includes aligned directors.

[0083] In one embodiment, along a small portion of the shortest thermal path 610 between the contact surface with the heat source 602 and the contact surface with the insulated area or insulated body 606, the director orientation of the LCE adjacent to the edge of the contact surface with the heat source 602 is perpendicular to the edge of the contact surface, thereby creating a highly conductive portion of the LCE along the shortest thermal path. This orientation continues for only a short threshold distance from the contact surface with the heat source 602. Thus, the shortest thermal path 610 can be configured to guide heat away from the heat source and diffuse the heat (and thermal path) over a larger area of ​​the LCE, after which the director orientation can be shifted so that the director is parallel (e.g., tangential) to the contact surface with the heat source 602 and parallel (e.g., tangential) to the contact surface with the insulated body 606. These embodiments of a portion of an LCE body having a director located near the node contact surface and perpendicular to the contact surface edge of the heat source 602 can be used when the heat flow from the heat source requires an additional heat path to carry heat away from the heat source, such that the director begins to orthogonal to the contact surface edge with the heat source, and after a threshold distance shift their orientation away from the insulator and possibly towards the heat sink 604. This orientation of the director is perpendicular to the contact surface edge with the heat source 602 (e.g., around a portion or all of the boundary of the heat source node in the thermal circuit, a particular portion that increases the heat flow in the vicinity of the LCE directly adjacent to the heat source). As shown by the map of director orientations, this local heat flow away from the heat source 602 (e.g., along the shortest heat path 610 between the heat source and the insulated area 606 over a threshold distance adjacent to the heat source) is present only in the portion of the shortest heat path 610 directly adjacent to the heat source contact surface so as to increase the area of ​​the shortest heat path to a realistic cross-section required to carry heat from the heat source.

[0084] This embodiment, in which a portion of the director is oriented perpendicular to the heat source contact surface in the adjacent portion of the shortest heat path 610, can be used in certain cases, such as when there is a large or significant anisotropy between the thermal conductivity of the LCE and a director orientation perpendicular to a parallel director orientation. For example, this embodiment can be used when there is a large heat flow requirement for the heat flow emanating from the contact surface with the heat source 602, and when there is a large anisotropic thermal conductivity such that the heat flow parallel to the director orientation is significantly better than the heat flow perpendicular to the director orientation. By using a director orientation perpendicular to the contact surface edge of the heat source on the contact surface portion of the LCE, the local heat flow across the contact surface edge can be increased in several portions of the contact surface with the heat sink.

[0085] Therefore, this embodiment of director orientation along the shortest thermal path can be used to avoid heat generation in portions of the heat source 602 that may cause the temperature of the heat source to rise outside of the operating parameters and / or create two temperatures along the node contact surface. If a node has a second temperature, the node is divided into two effective nodes, thereby creating a new thermal path, possibly a new dominant thermal path, based on the new node temperature. Different decisions can be made regarding director orientation along the shortest thermal path between nodes, based on the conductivity of the LCE body, the magnitude of the conductivity anisotropy between the heat flow orthogonal to the director orientation and the heat flow in the direction of the director orientation, and the requirement to reduce the heat flow entering and leaving the insulated area / insulated body 606.

[0086] In some embodiments, the requirements for the shortest heat path 612 through the LCE body between the heat sink 604 and the insulated body 606 may be designed similarly to those for the shortest heat path 610. For example, the requirements for constraining the heat flow along the shortest heat paths 610, 612 may be similar, especially when the temperature difference is similar between nodes, there are no asymmetric heat flow requirements (e.g., the insulated body must be insulated more from the heat source than from the heat sink), and / or when each node is arranged to be represented by three shortest heat paths having similar path lengths. In the illustrated embodiment, the LCE body includes similar director orientations along the shortest heat paths 610 and 612, but other design decisions may be made based on different heat flow requirements.

[0087] Figure 7 shows an embodiment of a thermal circuit incorporated into an LCE body 710 configured for use in an embodiment in which the contact surface with the insulated body 706 is located between the contact surface with the heat source 702 and the contact surface with the heat sink 704. Specific boundary conditions create different parameters for designing the director orientation of the LCE body, including physical boundary conditions of the LCE body such as physical edges 720 (e.g., the contact surface edge with the environment). As shown, the contact surface with the insulated body 706 is located between the contact surface portion with the heat sink 704 and the contact surface portion with the heat source 702, but the contact surface with the insulated body is not in the center of all portions of the contact surface with the heat source contact surface portion and the heat sink contact surface portion. Thus, there are different portions of the contact surface with the heat source 702 and the contact surface with the heat sink 704 that alternatively have a thermal path through the LCE separated by the insulated body 706, and several different portions of those nodes that have a direct thermal path passing near the contact surface with the insulated body.

[0088] In some embodiments, the physical boundary conditions of the LCE, including the surrounding boundary 720 of the LCE body 710, function to restrict direct heat paths between the heat source 702 and the heat sink 704. For example, the heat source 702 and the heat sink 704 may have heat flow requirements that are difficult to satisfy with respect to the number of heat paths between the two nodes, which are constrained by the physical limitations of the LCE, regardless of whether their limitations are due to in-plane constraints in Figure 7 or a combination of in-plane constraints and thickness constraints of the LCE body 710. These physical boundary constraints of the LCE may require further heat paths that are oriented for conduction but are neither linear nor shortest heat paths.

[0089] As shown in the embodiment of director orientation in Figure 7, the linear and shortest thermal paths between the heat source and the heat sink do not include directors that are generally oriented perpendicular to the contact surface edge of the heat source 702 and / or the contact surface of the heat sink 704 (e.g., directors that are all oriented along the direct thermal paths). In other words, in embodiments of the LCE body 710, the LCE body includes a director orientation selected for each part of the LCE body as a result of the increased requirement to limit the heat flow in and out of the insulated body 706. Thus, in some embodiments of the LCE body 710, the main design consideration is the amount of insulating LCE surrounding the insulated body 706. For example, in each part of the LCE body 710 surrounding the insulated body along the bottom of the physical boundary 720 of the LCE, all directors are oriented tangentially to the insulated body contact surface (e.g., along the LCE body boundary 720 and perpendicular to the shortest thermal path between the insulated body and the heat source). This director orientation extends from the portion of the LCE body adjacent to the contact surface with the insulated body 706 along both directions below the LCE boundary 720, thereby extending the insulated structure to the contact surface portion with the heat source 702 and the contact surface portion with the heat sink 704.

[0090] As shown in the embodiment of Figure 7, the design constraint prioritizing thermal insulation is merely one embodiment that allows the orientation of the director to always be aligned in the thermal insulation direction with respect to the contact surface with the insulated body 706, at least over a threshold distance from the insulated body, and that the director can be aligned between the heat source 702 and the heat sink 704 only in the portion of the LCE where these orientations are also aligned tangentially with the boundary of the insulated body.

[0091] In other embodiments where the heat flow requirements between the heat source 702 and the heat sink 704 exceed the heat flow requirements to enter and exit the insulated body 706, or where different anisotropies of thermal conductivity cause those requirements to interact with the physical constraints of the LCE body 720 differently, the orientation layout of the director in the embodiment shown in Figure 7 may be modified according to design decisions further described herein.

[0092] For example, without altering the physical boundary constraints 720 and without adding further thickness to the LCE body 710, different embodiments of director orientation and thermal paths within the LCE can be constructed to satisfy different heat flow requirements, such as aligning more directors with more direct paths between the heat source 702 and the heat sink 704. These different embodiments of director orientation can be further modified if more heat flow is possible to enter and exit the contact surface with the insulated body 706. Such different designs of directors can also be obtained in embodiments where the LCE material has higher thermal conductivity anisotropy between heat flows in different directions. In these embodiments, directors aligned with direct thermal paths can be included, where more direct thermal paths are closer to the contact surface with the insulated body 706 and further down the node contact surfaces of the heat source 702 and the heat sink 704. In such embodiments, heat conduction entering and exiting the insulated body can be sufficiently reduced due to the greater resistivity embodied in the thermal paths perpendicular to the director orientation.

[0093] In some embodiments, boundary conditions such as the physical boundary 720 can create portions of the LCE body 710 that are not important to the heat flow on the dominant heat path between the heat source 702 and the heat sink 704. Such portions are shown in Figure 7 without director orientation markings. These portions of the LCE body 710, located to the left of the heat source 702 and to the right of the heat sink 704 and shown without director orientation markings, may be insignificant to the heat flow in the heat circuit between the heat source 702, the heat sink 704, and the insulated body 706, because the respective lengths and relative thermal resistivity of the heat paths are very large in these areas, and the heat flow through these portions of the LCE body is negligible. In other words, in areas of the LCE body 710 without director orientation markings, the heat paths are necessarily longer and more heat-resistant than other heat paths where director orientation based on boundary conditions is indicated. Therefore, directors within these areas may be oriented for other conditions, such as routing heat between parts of the heat source 702 or between parts of the heat sink 704, thereby thermally stabilizing the node, or satisfying other boundary conditions, such as the LCE providing physical support for the node at the node contact surface without using air gaps for insulation.

[0094] The embodiments described herein may include specifications of only a portion of the node contact surfaces shown in Figure 7, and some of these embodiments may include other combinations of requirements relating to the contact surface edges and associated director orientation. For example, one embodiment may be designed to limit the heat flow to the contact surface with the insulated material without involving specific contact surfaces of the heat source and / or specific contact surfaces of the heat sink, and these nodes may instead be dispersed or partially defined from the ambient environment via absorption or emission of irradiation. In some embodiments, the LCE body may include a thermal circuit that includes only the requirement of heat flow along the conduction path between the heat source and the heat sink, and the insulated material contact surfaces within the LCE body are limited to or unaffected by the requirement for low heat flow to and from the heat source and / or heat sink. In other embodiments, the insulated material may be modeled to be dispersed, requiring containment of the heat flow between the heat source and the heat sink. In other embodiments, such as those described with respect to Figures 1 and 5, the insulated material (e.g., air, fluid) may be dispersed around a portion of the boundary of the LCE or over several portions of the boundary.

[0095] In some embodiments, a heat source / heat sink may include portions having different temperatures when the heat flow is at a particular level. These portions may exhibit different temperatures if they have very high and / or very different heat flows across the heat source 702 or heat sink 704. This temperature difference may mean that the design requirements for a thermal circuit incorporated into an LCE body include multiple heat sources or heat sinks, as indicated by the dashed portions of the heat source 702 and heat sink 704. The dashed portions of the heat source 702 and heat sink 704 may specify multiple nodes to be included in the design solution. The description herein regarding multiple separate thermal paths between nodes includes the interactions between these multiple nodes having different temperatures and different heat flow requirements. These common cases are described herein to include descriptions of solutions for multiple nodes, as well as solutions for thermal circuits of an LCE that include only one dispersed node, such as an insulating body independent of other heat flows around the LCE body.

[0096] In various embodiments, the disclosure relates to a liquid crystal elastomer composition having a liquid crystal elastomer having a heat sink contact surface edge perpendicular to the director orientation of the liquid crystal elastomer, wherein the liquid crystal elastomer is prepared by a method disclosed herein. For example, in some embodiments, the method includes extruding a portion of liquid crystal ink through a nozzle, thereby applying a shear force to the liquid crystal ink, i.e., (1) sufficient to align the director orientation of the liquid crystal ink by the shear force, and (2) oriented perpendicular to the heat sink contact surface edge of the liquid crystal elastomer. In various embodiments, the method further includes crosslinking the extruded portion of the liquid crystal ink with a portion of the liquid crystal elastomer having a director orientation by illuminating the extruded portion of the liquid crystal ink with ultraviolet light after the liquid crystal ink has exited the nozzle.

[0097] In some embodiments, the disclosure relates to a liquid crystal polymer composition having a liquid crystal polymer having a heat sink contact surface edge perpendicular to the director orientation of the liquid crystal polymer, wherein the liquid crystal polymer is prepared by a method disclosed herein. For example, in some embodiments, the method includes: placing a liquid crystal mesogen mixture prepared in a non-stoichiometric ratio of functional groups for a Michael addition reaction in contact with a heat sink contact surface; reacting the liquid crystal mesogen mixture while it is in contact with the heat sink contact surface until the reaction stops due to the non-stoichiometric ratio, thereby creating an intermediate liquid crystal polymer having an excess of unreacted functional groups including a heat sink contact surface edge in contact with the heat sink contact surface; straining the liquid crystal polymer away from the heat sink contact surface edge; and exposing the intermediate liquid crystal polymer having an excess of unreacted functional groups to a crosslinking stimulus configured to react the excess of unreacted functional groups, thereby creating a liquid crystal polymer having a heat sink contact surface edge.

[0098] In another embodiment, the disclosure relates to a liquid crystal polymer composition having a liquid crystal polymer having a thermal insulation contact surface edge aligned with the director orientation of the liquid crystal polymer, wherein the liquid crystal polymer is prepared by a method disclosed herein. For example, in some embodiments, the method includes: placing a liquid crystal mesogen mixture prepared in a non-stoichiometric ratio of functional groups for a Michael addition reaction in contact with a thermal insulation contact surface; reacting the liquid crystal mesogen mixture while it is in contact with the thermal insulation contact surface until the reaction stops due to the non-stoichiometric ratio, thereby creating an intermediate liquid crystal polymer having an excess of unreacted functional groups including a thermal insulation contact surface edge in contact with the thermal insulation contact surface; straining the liquid crystal polymer in a direction parallel to the thermal insulation contact surface edge; and exposing the intermediate liquid crystal polymer having an excess of unreacted functional groups to a crosslinking stimulus configured to react a group of excess unreacted functional groups, thereby creating a liquid crystal polymer having a thermal insulation contact surface edge.

[0099] Various embodiments of this disclosure are shown in the accompanying drawings and described in the detailed description above, but it will be understood that this disclosure is not limited to the embodiments disclosed herein and that numerous reconfigurations, modifications, and substitutions are possible without departing from the spirit of the disclosure described herein.

[0100] The term “substantially” is defined as being largely as described, but not necessarily as such, as understood by those skilled in the art. In any disclosed embodiment, the terms “substantially,” “approximately,” “nearly,” and “about” may be replaced by “within ~[percentage]” of the specified, where the percentages include 0.1, 1, 5, and 10 percent.

[0101] The above outlines some features of embodiments so that those skilled in the art may better understand aspects of the present disclosure. Those skilled in the art will understand that the present disclosure can be readily used as a basis for designing or modifying other methods and structures to perform the same purposes and / or achieve the same advantages as the embodiments introduced herein. Those skilled in the art will also understand that such equivalent configurations do not depart from the spirit and scope of the present disclosure, and that various changes, substitutions, and modifications can be made herein without departing from the spirit and scope of the present disclosure. The scope of the present invention should be determined solely by the following claims language. The term “comprising” in the claims is intended to mean “including at least” so that the list of enumerated elements in the claims is an open group. The terms “a,” “an,” and other singular terms are intended to include their plural forms unless specifically excluded.

Claims

1. A liquid crystal elastomer body is configured to include a thermal circuit that connects a heat source to a heat sink via a plurality of first thermal paths from the heat source through the liquid crystal elastomer body to the heat sink, wherein the plurality of first thermal paths include the shortest first thermal path, which is configured to align more than the first majority of directors along the shortest first thermal path. The thermal circuit of the liquid crystal elastomer is further configured to connect the heat source to the insulated material via a plurality of second thermal paths from the heat source through the liquid crystal elastomer to the insulated material, wherein the plurality of second thermal paths include a second thermal path configured to be more orthogonal than the second majority of directors along the shortest second thermal path. The thermal circuit of the liquid crystal elastomer is further configured to connect the insulated body to the heat sink via a plurality of third thermal paths from the insulated body through the liquid crystal elastomer to the heat sink, wherein the plurality of second thermal paths include the shortest third thermal path, which is configured to be orthogonal to more than the third majority of directors of the shortest third thermal path. Liquid crystal elastomer composition.

2. The liquid crystal elastomer composition according to claim 1, wherein the shortest first thermal path between the heat source and the heat sink is longer than the shortest second thermal path between the heat source and the insulated object.

3. The liquid crystal elastomer composition according to claim 1, wherein the liquid crystal elastomer body includes a director oriented along the shortest second heat path, along a portion of the shortest second heat path adjacent to the heat source.

4. The liquid crystal elastomer composition according to claim 1, wherein the liquid crystal elastomer includes a director oriented perpendicular to the shortest second heat path along the majority of the shortest second heat path passing through the liquid crystal elastomer between the heat source and the insulated body.

5. The majority of the shortest second heat path is the uninterrupted portion of the shortest second heat path that is closer to the insulated object than the heat source. The liquid crystal elastomer composition according to claim 4, wherein the uninterrupted portion of the shortest second heat path through the liquid crystal elastomer is more permeable than a small portion of the shortest second heat path that is separate from the majority portion of the shortest second heat path.

6. The liquid crystal elastomer composition according to claim 5, wherein the uninterrupted portion of the shortest second heat path is adjacent to the insulated body.

7. The liquid crystal elastomer composition according to claim 1, wherein the liquid crystal elastomer body includes a director oriented along the shortest third heat path, along a portion of the shortest third heat path adjacent to the heat sink.

8. The liquid crystal elastomer composition according to claim 1, wherein the liquid crystal elastomer includes a director oriented perpendicular to the shortest third heat path along the majority portion of the shortest third heat path passing through the liquid crystal elastomer between the heat sink and the insulated body.

9. The majority of the shortest third thermal path is the uninterrupted portion of the shortest third thermal path that is closer to the insulated material than the heatsink. The liquid crystal elastomer composition according to claim 8, wherein the uninterrupted portion of the shortest third thermal path through the liquid crystal elastomer is more permeable than a small portion of the shortest third thermal path that is separate from the majority portion of the shortest third thermal path.

10. The liquid crystal elastomer composition according to claim 9, wherein the uninterrupted portion of the shortest third heat path is adjacent to the insulated body.

11. The liquid crystal elastomer composition according to claim 1, wherein the liquid crystal elastomer body contains a monodomain of a director oriented along the shortest first thermal path passing through the liquid crystal elastomer body between a heat source and a heat sink.

12. The liquid crystal elastomer composition according to claim 1, wherein the majority of the first, second, and third directors each represent more than 50% of the directors.

13. The liquid crystal elastomer composition according to claim 1, wherein the majority of the first, second, and third directors each represent more than 75% of the directors.

14. The liquid crystal elastomer composition according to claim 1, wherein the majority of the first, second, and third directors each represent more than 90% of the directors.

15. The liquid crystal elastomer composition according to claim 1, wherein the liquid crystal elastomer composition is at least one of a flexible electronic device or a flexible display.

16. A liquid crystal elastomer body is included, configured to include a thermal circuit that includes the contact surface portion of the insulated body node of the liquid crystal elastomer body, The insulated node contact surface portion includes a director configured to align parallel to the contact surface edge of the insulated node contact surface portion, Liquid crystal elastomer composition.

17. The heat sink node contact surface portion of the liquid crystal elastomer body further includes a director configured to be aligned perpendicularly to the contact surface edge of the heat sink node contact surface portion, The liquid crystal elastomer composition according to claim 16.

18. The liquid crystal elastomer composition according to claim 17, comprising all of the liquid crystal elastomer bodies configured such that the heat sink node contact surface portion contacts the heat sink.

19. The heat source node contact surface portion of the liquid crystal elastomer body further includes a director configured to be aligned perpendicularly to the contact surface edge of the heat source node contact surface portion, The liquid crystal elastomer composition according to claim 16.

20. The liquid crystal elastomer composition according to claim 19, comprising all of the liquid crystal elastomer bodies configured such that the heat source node contact surface portion is in contact with a heat source.

21. The liquid crystal elastomer composition according to claim 16, comprising all of the liquid crystal elastomer bodies configured such that the portion of the node contact surface of the insulated body is in contact with the insulated body.

22. The liquid crystal elastomer composition according to claim 15, wherein the liquid crystal elastomer composition is at least one of a flexible electronic device or a flexible display.

23. A method for creating a liquid crystal elastomer having a heat sink contact surface edge that is perpendicular to the director orientation of the liquid crystal elastomer, This includes pushing out a portion of the liquid crystal ink through the nozzle. By pushing, shear force is applied to the liquid crystal ink, that is, The shear force is sufficient to align the director orientation of the liquid crystal ink. It is oriented perpendicular to the edge of the heat sink contact surface of the liquid crystal elastomer body, and, This method involves illuminating the extruded portion of the liquid crystal ink with ultraviolet light after the liquid crystal ink exits the nozzle, thereby crosslinking the extruded portion of the liquid crystal ink to a portion of a liquid crystal elastomer having a director orientation. method.

24. Pushing out a portion of the liquid crystal ink is equivalent to initially pushing out the first portion of the liquid crystal ink. By illuminating the extruded portion of the liquid crystal ink with ultraviolet light, the extruded portion of the liquid crystal ink is crosslinked to a portion of the liquid crystal elastomer having a director orientation; by illuminating the first extruded portion of the liquid crystal ink with ultraviolet light, the first extruded portion of the liquid crystal ink is crosslinked to the first portion of the liquid crystal elastomer having a director orientation. The method is The process involves pushing out a second portion of the liquid crystal ink through the nozzle, After the second extrusion of the second portion of the liquid crystal ink, both the first portion of the liquid crystal elastomer and the second portion of the liquid crystal ink are illuminated with ultraviolet light, thereby crosslinking the second portion of the liquid crystal ink to the second portion of the liquid crystal elastomer. The method according to claim 23, further comprising:

25. The method according to claim 24, wherein the second illumination further chemically bonds the first portion of the liquid crystal elastomer with the second portion of the liquid crystal elastomer.

26. Multiple extrusion cycles that extrude multiple parts of the liquid crystal ink, Multiple crosslinking cycles, which include creating multiple parts of a liquid crystal elastomer by illuminating each of multiple parts of a liquid crystal ink multiple times with ultraviolet light, After a cycle of multiple illuminations with ultraviolet light, the liquid crystal elastomer is illuminated a third time with ultraviolet light, in addition to the first and second parts of the liquid crystal elastomer. The method according to claim 24, further comprising:

27. The method according to claim 23, further comprising holding a source of ultraviolet light at a predetermined distance from the nozzle.

28. A method for creating a liquid crystal polymer having a heat sink contact surface edge that is perpendicular to the director orientation of the liquid crystal polymer, A liquid crystal mesogen mixture prepared in a non-stoichiometric ratio of functional groups for a Michael addition reaction is placed in contact with the molded surface of the heat sink contact surface, The liquid crystal mesogen mixture is reacted with the heat sink contact surface molding until the reaction stops due to a non-stoichiometric ratio, thereby creating an intermediate liquid crystal polymer body having an excess of unreacted functional groups, including the heat sink contact surface edge that is in contact with the heat sink contact surface molding. The liquid crystal polymer is deformed in a direction away from the edge of the heat sink contact surface, An intermediate liquid crystal polymer having an excess of unreacted functional groups is exposed to a crosslinking stimulus configured to react the excess of unreacted functional groups, thereby creating a liquid crystal polymer having a heat sink contact surface edge. Methods that include...

29. The method according to claim 28, wherein the distortion is carried out for a predetermined strain rate of the liquid crystal polymer based on a predetermined desired percentage director orientation aligned with the direction of the strain.

30. The method according to claim 28, wherein the straining is performed to maintain the strain rate in the liquid crystal polymer while the exposure process is being carried out.

31. The method according to claim 28, wherein the liquid crystal polymer body is shaped to a degree exceeding 90% of the strain value applied during the deformation process.

32. A method for creating a liquid crystal polymer having a director orientation of the liquid crystal polymer body and an edge portion of the thermal insulation material contact surface aligned with that orientation, A liquid crystal mesogen mixture prepared in a non-stoichiometric ratio of functional groups for a Michael addition reaction is placed in contact with the molded surface of the thermal insulation material, The liquid crystal mesogen mixture is reacted with the molded surface of the heat insulating material until the reaction stops due to a non-stoichiometric ratio, thereby creating an intermediate liquid crystal polymer body having an excess of unreacted functional groups, including the edge of the heat insulating material contact surface that is in contact with the molded surface of the heat insulating material. The liquid crystal polymer is deformed in a direction parallel to the edge of the contact surface with the heat insulating material, An intermediate liquid crystal polymer having an excess of unreacted functional groups is exposed to a crosslinking stimulus configured to react the excess of unreacted functional groups, thereby creating a liquid crystal polymer having an edge portion of the thermal insulation contact surface. Methods that include...

33. The method according to claim 32, wherein the distortion is carried out for a predetermined strain rate of the liquid crystal polymer based on a predetermined desired percentage director orientation aligned with the direction of the strain.

34. The method according to claim 32, wherein the straining is performed to maintain the strain rate in the liquid crystal polymer while the exposure process is carried out.

35. The method according to claim 32, wherein the liquid crystal polymer body is shaped to a degree exceeding 90% of the strain value applied during the deformation process.

36. A method for creating a liquid crystal polymer having a heat sink contact surface edge that is perpendicular to the director orientation of the liquid crystal polymer, Applying an anchoring agent to the molded surface of the heat sink contact surface, A liquid crystal mesogen mixture prepared in a non-stoichiometric ratio of functional groups for a Michael addition reaction is placed in contact with the molded surface of the heat sink contact surface, The liquid crystal mesogen mixture is reacted with the heat sink contact surface molding until the reaction stops due to a non-stoichiometric ratio, thereby creating an intermediate liquid crystal polymer body having an excess of unreacted functional groups, including the heat sink contact surface edge that is in contact with the heat sink contact surface molding. An intermediate liquid crystal polymer having an excess of unreacted functional groups is exposed to a crosslinking stimulus configured to react the excess of unreacted functional groups, thereby creating a liquid crystal polymer having a heat sink contact surface edge. Methods that include...

37. The method according to claim 36, wherein the anchoring agent is flat so as to create an alignment parallel to the heat sink contact surface.

38. The method according to claim 36, wherein the anchoring agent comprises polyimide.

39. The method according to claim 36, wherein the anchoring agent comprises a polyamide.

40. The method according to claim 36, further comprising rubbing the anchoring agent with felt to induce a director profile.

41. The method according to claim 36, wherein the anchoring agent is homeotropic so as to create an alignment perpendicular to the heat sink contact surface.

42. The method according to claim 36, wherein the anchoring agent is flat so as to create an alignment parallel to the heat sink contact surface.

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