CN-122011762-A - AZC@LDH-based high-heat-conductivity flexible composite phase change membrane

CN122011762ACN 122011762 ACN122011762 ACN 122011762ACN-122011762-A

Abstract

The invention relates to a high-heat-conductivity flexible composite phase-change film based on AZC@LDH, and a preparation method and application thereof, and belongs to the technical field of composite phase-change materials and thermal safety regulation and control. The composite phase change membrane is prepared from a flexible self-supporting film skeleton and ACZ@LDH nano heat conduction filler uniformly dispersed in the flexible self-supporting film skeleton through a simple process of one-step blending and solution casting, wherein the flexible self-supporting film skeleton is a PEI/CMC three-dimensional network matrix which is loaded with polyethylene glycol phase change materials and limits the polyethylene glycol phase change materials, and the ACZ@LDH nano heat conduction filler is a core-shell structure nano hybridization filler formed by growing lamellar double metal hydroxide nano sheets on the surface of a ZIF-8 derived porous carbon material. The composite phase-change film has excellent flexibility, shape stability and high thermal conductivity, integrates high-efficiency photo-thermal conversion/energy storage and active thermal runaway inhibition functions, and is suitable for the fields of battery thermal management, solar photo-thermal utilization, microelectronic thermal protection and the like.

Inventors

HUANG QUE
ZHANG WENYUE
LIU CHANGCHENG
GUO LI
YANG JINLU
Hua Muhui

Assignees

中南大学
中北大学

Dates

Publication Date: 20260512
Application Date: 20260115

Claims (10)

1. A high-heat-conductivity flexible composite phase change membrane based on AZC@LDH is composed of a flexible self-supporting film skeleton and ACZ@LDH nano heat-conducting filler uniformly dispersed therein, wherein: The flexible self-supporting film skeleton comprises a PEI/CMC three-dimensional network matrix formed by crosslinking polyethyleneimine and sodium carboxymethylcellulose through intermolecular forces, and polyethylene glycol phase-change materials which are uniformly dispersed and confined in the three-dimensional network matrix; the ACZ@LDH nano heat-conducting filler is a nano hybrid filler with a core-shell structure, which is formed by ZIF-8 derived porous carbon materials serving as cores and lamellar double-metal hydroxide nano sheets growing and supported on the surfaces of the cores; the composite phase-change film has flexibility and self-supporting property at room temperature, and keeps stable shape in a phase-change temperature range of polyethylene glycol.
2. The azc@ldh-based high thermal conductivity flexible composite phase change membrane according to claim 1, wherein the ZIF-8 derived porous carbon material is a KOH-activated porous carbon material.
3. The azc@ldh-based high thermal conductivity flexible composite phase change membrane according to claim 1, wherein the layered double hydroxide nanoplatelets are magnesium aluminum hydrotalcite MgAl-LDH.
4. The azc@ldh-based high-thermal-conductivity flexible composite phase-change membrane of claim 1, 2 or 3, wherein the composite phase-change membrane is composed of 50-70wt% of polyethylene glycol phase-change material, 25-40wt% of PEI/CMC three-dimensional network matrix and 5-10wt% of acz@ldh nano thermal-conductive filler.
5. The AZC@LDH-based high-heat-conductivity flexible composite phase-change film disclosed in claim 4 is characterized in that the content of each component constituting the composite phase-change film is 55-65wt% of polyethylene glycol phase-change material, 30-38wt% of PEI/CMC three-dimensional network matrix and 8-10wt% of ACZ@LDH nano heat-conducting filler.
6. The azc@ldh-based high-thermal-conductivity flexible composite phase-change film according to claim 1, wherein the polyethylene glycol phase-change material has an average molecular weight of 2000-10000.
7. The method for preparing the high-heat-conductivity flexible composite phase-change film based on AZC@LDH of claim 1, which comprises the following steps: dissolving polyethyleneimine and sodium carboxymethyl cellulose in water, adding polyethylene glycol, and uniformly mixing to obtain PEG-PC precursor solution; taking a ZIF-8 derived porous carbon material as a core, and adopting a hydrothermal method to grow a layered double hydroxide nano sheet on the surface of the porous carbon material in situ to obtain the ACZ@LDH nano heat-conducting filler with a core-shell structure; dispersing ACZ@LDH nano heat conducting filler in a PEG-PC precursor solution to obtain composite slurry, casting into a film by adopting a solution casting method, and drying to obtain the AZC@LDH-based high heat conducting flexible composite phase change film.
8. The application of the AZC@LDH-based high-heat-conductivity flexible composite phase change film in preparation of an integrated thermal management device with heat energy storage and thermal runaway inhibition functions.
9. The use according to claim 8, wherein the integrated thermal management device is selected from any one of a thermal management device for rechargeable battery modules to achieve both battery waste heat storage/utilization and thermal runaway propagation inhibition, a thermal management device for solar photo-thermal systems to achieve both photo-thermal conversion, thermal energy storage and self-overheat protection, and a flexible thermal buffer material for microelectronic packaging or intelligent building enclosures to achieve both thermal buffer regulation and fire safety protection.
10. The application of the AZC@LDH-based high-heat-conductivity flexible composite phase change film in preparing flame-retardant heat-insulating protective materials.

Description

AZC@LDH-based high-heat-conductivity flexible composite phase change membrane Technical Field The invention belongs to the technical field of advanced thermal management function composite materials, relates to a composite phase change material with functions of photo-thermal conversion/energy storage and thermal runaway inhibition, and particularly relates to a high-heat-conductivity, flexible and flame-retardant composite phase change film material and a preparation method thereof. Background Information technology is continuously developed, and portable electronic devices, wearable devices, high-energy-density batteries and the like are increasingly evolving towards light weight, miniaturization and high power. In this trend, the amount of heat generated per unit volume during operation of the apparatus increases drastically, resulting in a significant increase in heat flux density. The abnormal rise of the temperature of the equipment can cause a series of serious problems, namely, the equipment is overheated to have fire hidden danger, the safety of users is endangered, and the high temperature can accelerate the aging of internal electronic components and prolong the service life of the equipment. Therefore, developing efficient thermal management techniques and materials to achieve rapid heat dissipation of electronic devices or batteries and maintain a proper operating temperature range has become a critical technical problem to be solved. Phase Change Materials (PCM) exhibit great application potential in the field of thermal management by virtue of their reversible phase change behavior and the characteristic of exhibiting higher energy storage density at smaller temperature differences. The phase change material has the main functions of storing and releasing energy by the identity of a transfer station in the process of reversible phase change behavior, realizing efficient heat 'time translation' under the condition of nearly constant temperature, being beneficial to energy saving and peak load transfer, and providing an ideal solution for maintaining equipment to operate in a proper temperature range. Compared with other phase-change materials, the solid-liquid phase-change material has relatively high energy storage capacity in a smaller temperature difference range, and meanwhile, the volume change is ensured to be relatively stable in the phase-change process, so that the limitation of more application scenes can be overcome. However, solid-liquid phase change materials, particularly polyethylene glycol (PEG), which is the most widely used organic phase change material, have obvious technical defects that firstly, leakage easily occurs during solid-liquid transition to affect the stability and safety of devices, secondly, the intrinsic heat conductivity coefficient is generally low, the absorption/heat release rate of the solid-liquid phase change material is limited, and thirdly, the flexibility and the photo-thermal conversion capability are insufficient. These drawbacks in terms of flexibility, thermal conductivity, leakage sensitivity, and photothermal conversion capability severely limit their wide application in the thermal safety management of advanced electronic devices. The prior art mainly overcomes the problems of leakage and poor thermal conductivity through strategies such as microencapsulation, porous carrier adsorption or polymer network encapsulation. However, although the microcapsule technology or the porous material (such as expanded graphite, porous silica, etc.) loaded with PEG can inhibit leakage to a certain extent, the preparation process is often complicated, the production cost is high, and environmentally unfriendly substances may be introduced, so that the method does not conform to the sustainable development concept of green. Although the PCM encapsulated by the three-dimensional polymer network constructed by chemical crosslinking can effectively improve the shape stability and the leakage-proof performance, the compact and irreversible crosslinking network causes the material to be difficult to recycle and reuse, and meanwhile, the ordered arrangement of molecular chains is challenging. In addition, the thermoplastic elastomer is physically packaged through a microphase separation structure, so that the process is relatively simple, but the problems of low phase change material loading rate, remarkably reduced latent heat energy storage capacity, limited biocompatibility and the like exist, and the difficulty of recycling is faced after the waste thermoplastic elastomer is discarded. Jing et al （Flexible electrospun porous carbon nanofiber@PEG phase change nanofibrous membrane for advanced solar-/electro-thermal energy conversion and storage[J].Journal of Energy Storage, 2024, 104: 114608.） encapsulates PEG in a firm flexible Porous Carbon Nanofiber (PCNFs) derived from an electrospun polyacrylonitrile/polystyrene (PAN/PS) composite nanofiber, and the prepared