Advances and mechanisms in polymer composites toward thermal conduction and electromagnetic wave absorption

Science Bulletin, Год журнала: 2023, Номер 68(11), С. 1195 - 1212

Опубликована: Май 2, 2023

Язык: Английский

---

Electric‐Field‐Induced Alignment of Functionalized Carbon Nanotubes Inside Thermally Conductive Liquid Crystalline Polyimide Composite Films

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(38)

Опубликована: Авг. 7, 2023

The positive liquid crystals, 4'-heptyl-4-biphenylcarbonitrile (7CB), are used to functionalize carbon nanotubes (LC-CNT), which can be aligned in the crystalline polyimide (LC-PI) matrix under an alternating electric field fabricate thermally conductive LC-CNT/LC-PI composite films. efficient establishment of thermal conduction pathways films with a low amount LC-CNT is achieved through oriented alignment within LC-PI matrix. When mass fraction 15 wt %, in-plane conductivity coefficient (λ∥ ) and through-plane (λ⊥ reach 4.02 W/(m ⋅ K) 0.55 W/(m⋅K), 90.5 % 71.9 higher than those intrinsically respectively, also 28.8 5.8 CNT/LC-PI respectively. Meanwhile, possess excellent mechanical heat resistance properties. Young's modulus index 2.3 GPa 297.7 °C, same CNT.

Язык: Английский

---

Leakage Proof, Flame-Retardant, and Electromagnetic Shield Wood Morphology Genetic Composite Phase Change Materials for Solar Thermal Energy Harvesting

Nano-Micro Letters, Год журнала: 2024, Номер 16(1)

Опубликована: Май 16, 2024

Abstract Phase change materials (PCMs) offer a promising solution to address the challenges posed by intermittency and fluctuations in solar thermal utilization. However, for organic solid–liquid PCMs, issues such as leakage, low conductivity, lack of efficient solar-thermal media, flammability have constrained their broad applications. Herein, we present an innovative class versatile composite phase (CPCMs) developed through facile environmentally friendly synthesis approach, leveraging inherent anisotropy unidirectional porosity wood aerogel (nanowood) support polyethylene glycol (PEG). The modification process involves incorporation phytic acid (PA) MXene hybrid structure evaporation-induced assembly method, which could impart non-leaking PEG filling while concurrently facilitating conduction, light absorption, flame-retardant. Consequently, as-prepared wood-based CPCMs showcase enhanced conductivity (0.82 W m −1 K , about 4.6 times than PEG) well high latent heat 135.5 kJ kg (91.5% encapsulation) with durability stability throughout at least 200 heating cooling cycles, featuring dramatic conversion efficiency up 98.58%. In addition, synergistic effect MXene, flame-retardant performance has been significantly enhanced, showing self-extinguishing behavior. Moreover, excellent electromagnetic shielding 44.45 dB was endowed CPCMs, relieving contemporary health hazards associated waves. Overall, capitalize on exquisite cell transport development multifunctional showcasing operational principle proof-of-concept prototype system.

Язык: Английский

---

Ultraflexible, cost-effective and scalable polymer-based phase change composites via chemical cross-linking for wearable thermal management

Nature Communications, Год журнала: 2023, Номер 14(1)

Опубликована: Дек. 5, 2023

Phase change materials (PCMs) offer great potential for realizing zero-energy thermal management due to superior storage and stable phase-change temperatures. However, liquid leakage solid rigidity of PCMs are long-standing challenges PCM-based wearable regulation. Here, we report a facile cost-effective chemical cross-linking strategy develop ultraflexible polymer-based phase composites with dual 3D crosslinked network olefin block copolymers (OBC) styrene-ethylene-butylene-styrene (SEBS) in paraffin wax (PW). The C-C bond-enhanced OBC-SEBS networks synergistically improve the mechanical, thermal, leakage-proof properties PW@OBC-SEBS. Notably, proposed peroxide-initiated method overcomes limitations conventional physical blending methods thus can be applicable across diverse polymer matrices. We further demonstrate portable flexible PW@OBC-SEBS module that maintains comfortable temperature range 39-42 °C personal thermotherapy. Our work provides promising route fabricate scalable composite management.

Язык: Английский

---

Temperature-Arousing Self-Powered Fire Warning E-Textile Based on p–n Segment Coaxial Aerogel Fibers for Active Fire Protection in Firefighting Clothing

Nano-Micro Letters, Год журнала: 2023, Номер 15(1)

Опубликована: Окт. 13, 2023

Firefighting protective clothing is a crucial equipment for firefighters to minimize skin burn and ensure safety firefighting operation rescue mission. A recent increasing concern develop self-powered fire warning materials that can be incorporated into the achieve active protection before catches on fireground. However, it still challenge facilely design manufacture thermoelectric (TE) textile (TET)-based electronics with dynamic surface conformability breathability. Here, we an alternate coaxial wet-spinning strategy continuously produce alternating p/n-type TE aerogel fibers involving n-type Ti3C2Tx MXene p-type MXene/SWCNT-COOH as core materials, tough aramid nanofiber shell, which simultaneously flexibility high-efficiency power generation. With such fibers, TET-based sensors high mechanical stability wearability are successfully fabricated through stitching p-n segment fabric. The results indicate containing 50 pairs open-circuit voltage of 7.5 mV density 119.79 nW cm-2 at temperature difference 300 °C. output signal then calculated corresponding based linear relationship between temperature. alarm response time flame-retardant properties further displayed. Such true textiles offer breathability compatibility body movement, demonstrating their potential application in clothing.

Язык: Английский

---

Functional Materials and Innovative Strategies for Wearable Thermal Management Applications

Nano-Micro Letters, Год журнала: 2023, Номер 15(1)

Опубликована: Июнь 29, 2023

Thermal management is essential in our body as it affects various bodily functions, ranging from thermal discomfort to serious organ failures, an example of the worst-case scenario. There have been extensive studies about wearable materials and devices that augment thermoregulatory functionalities body, employing diverse systematic approaches attaining homeostasis. This paper reviews recent progress functional contribute wearables, particularly emphasizing strategic methodology regulate temperature. exist several methods promote personal a form. For instance, we can impede heat transfer using thermally insulating material with extremely low conductivity or directly cool skin surface. Thus, classify many into two branches, passive active modes, which are further subdivided specific strategies. Apart discussing strategies their mechanisms, also identify weaknesses each strategy scrutinize its potential direction should follow make substantial contributions future regulatory industries.

Язык: Английский

---

Novel multifunctional melamine borate - boron nitride nanosheets/epoxy composites with enhanced thermal conductivity, flame retardancy and satisfying electrical insulation

Composites Part A Applied Science and Manufacturing, Год журнала: 2023, Номер 169, С. 107495 - 107495

Опубликована: Фев. 26, 2023

Язык: Английский

---

NH3-Induced In Situ Etching Strategy Derived 3D-Interconnected Porous MXene/Carbon Dots Films for High Performance Flexible Supercapacitors

Nano-Micro Letters, Год журнала: 2023, Номер 15(1)

Опубликована: Окт. 18, 2023

2D MXene (Ti3CNTx) has been considered as the most promising electrode material for flexible supercapacitors owing to its metallic conductivity, ultra-high capacitance, and excellent flexibility. However, it suffers from a severe restacking problem during fabrication process, limiting ion transport kinetics accessibility of ions in electrodes, especially direction normal surface. Herein, we report NH3-induced situ etching strategy fabricate 3D-interconnected porous MXene/carbon dots (p-MC) films high-performance supercapacitor. The pre-intercalated carbon (CDs) first prevent expose more inner electrochemical active sites. partially decomposed CDs generate NH3 nanosheets toward p-MC films. Benefiting structural merits ionic transmission channels, film electrodes achieve gravimetric capacitance (688.9 F g-1 at 2 A g-1) superior rate capability. Moreover, optimized is assembled into an asymmetric solid-state supercapacitor with high energy density cycling stability, demonstrating great promise practical applications.

Язык: Английский

---

Application-Driven High-Thermal-Conductivity Polymer Nanocomposites

ACS Nano, Год журнала: 2024, Номер 18(5), С. 3851 - 3870

Опубликована: Янв. 24, 2024

Polymer nanocomposites combine the merits of polymer matrices and unusual effects nanoscale reinforcements have been recognized as important members material family. Being a fundamental property, thermal conductivity directly affects molding processing materials well design performance devices systems. used in numerous industrial fields; thus, high demands are placed on feature nanocomposites. In this Perspective, we first provide roadmaps for development with isotropic, in-plane, through-plane conductivities, demonstrating great effect enhancement Then significance different application fields, including wearable electronics, interface materials, battery management, dielectric capacitors, electrical equipment, solar energy storage, biomedical applications, carbon dioxide capture, radiative cooling, highlighted. future research, should continue to focus methods that can further improve On other hand, pay more attention synergistic improvement properties Emerging be based application-oriented research.

Язык: Английский

---

Flexible insulating phase change composite film with improved thermal conductivity for wearable thermal management

Nano Energy, Год журнала: 2024, Номер 121, С. 109256 - 109256

Опубликована: Янв. 4, 2024

Язык: Английский

---