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Polyacrylate‐based electrically conductive adhesives (PA‐based ECAs) have attracted much attention due to their wide applications in precise instruments and consumer electronics. To obtain high‐performance and environmentally friendly PA‐based ECAs, their main properties and corresponding mechanisms to performance, chemical constitutions and structure–function relationships should be well understood, and the applications of recent PA‐based ECAs should be comprehensively summarized. This review focuses on the progress of PA‐based ECAs in the past two decades and discusses the featured properties, preparation of PA, the selection of conductive fillers and the adhibition of the ECAs. The aim of the review is to find the challenges of high‐performance ECAs and offer some measures and foresee their future development. Highlights: Preparation methods of polyacrylate (PA)‐based composites are presented.Properties of PA‐based electrically conductive adhesives (ECAs) are outlined.Selection of conductive fillers and the adhibition of ECAs are discussed.Representative applications of PA‐based ECAs are exhibited.Present main challenges and future solutions are highlighted. [ABSTRACT FROM AUTHOR]

With the rapid growth of highly integrated electrical devices, the urgent demand for polymer composites with high thermal conductivity (TC) is increasing for effective thermal management. In this work, boron nitride nanosheets (BNNSs) were chemically grafted with aluminum oxide (Al2O3) to develop hetero‐structured filler (BNNSs@Al2O3). The BNNSs@Al2O3 fillers were uniformly dispersed in the poly(vinyl alcohol) (PVA) by solvent mixing, verified by SEM, and the oriented BNNSs@Al2O3/PVA composites were produced by the doctor blade method. The results exhibited that the synergistic effect of BNNSs and Al2O3 was achieved, and the thermal conductivities of BNNSs@Al2O3/PVA composites were improved. When keeping the filler content at 30 wt%, the in‐plane and out‐of‐plane TC of BNNSs@Al2O3/PVA composite reached 5.641 and 0.651 W/(m·K), respectively. The BNNSs@Al2O3 filler may improve the performance of composite heat dissipation by reducing the interfacial resistance between fillers and making it easier to establish directed heat‐transfer pathways. This composite demonstrates promising application in the field of electronic packaging. [ABSTRACT FROM AUTHOR]

The high demand for thermally conductive materials in the housing and packaging industry of electronic device highlights the necessity for the development of novel thermal conductivity materials. In this study, waste poplar wood was delignified and combined with boron nitride (hBN) to establish a blend system with a cross thermally conductive network. Using the vacuum‐assisted resin transfer molding process, a biobased composite material was prepared with high thermal conductivity (1.41 W m−1 K−1), mechanical strength (flexural strength of 100.7 MPa and tensile strength of 40.0 MPa), flame retardancy, and water resistance. Compared with raw wood, the incorporation of hBN increased the thermal conductivity of the prepared material by 1324.2%. The high thermal conductivity performance surpassed that of most polymers and elastomers commonly used in electronic component heat dissipation materials, indicating the enormous potential of the prepared composite material in the field of heat dissipation materials. [ABSTRACT FROM AUTHOR]

Enhancing the thermal conductivity of epoxy resin is an urgent demand for its application in electronic packaging field. In this work, thermally conductive epoxy/graphite composite featuring excellent self‐healing and reprocessability is prepared based on covalent adaptable networks. The effect of graphite on the rheology, reprocessing, and self‐healing properties of epoxy have been studied. The result shows that the prepared composites can be easily reprocessed and have excellent self‐healing property. On the fundamental of the highly multifunctional performance of the epoxy composites, highly thermally conductive bulk composites are constructed via multilayered stacking up and self‐healing based on the film composites, which is prepared using a rolling method. It is demonstrated that the films can assemble into new substance bulk by stacking up through self‐healing. The high thermal conductivity is achieved by the highly aligned graphite induced by the rolling process. Result reveals that, being filled with 50% mass fraction of GR, the bulk composites possesses high thermal conductivity of 8.411 Wm−1 K−1. This work provides a new strategy to prepare recyclable and highly thermally conductive epoxy. [ABSTRACT FROM AUTHOR]

The mismatch of coefficient of thermal expansion (CTE) of components has created numerous reliability issues in electronic packages. Incorporating inorganic fillers into polymer matrices has been proven to be an effective way to reduce the CTE, but properly balancing CTE with other key properties of the composites is still a challenge. In the current work, negative thermal expansion Zr2WP2O12 (ZWP) particles were prepared by a high‐temperature solid‐phase synthesis method. Polyphenylene oxide (PPO)‐based composites with different volume fractions (0, 10, 20, 30 vol%) of ZWP particles were prepared and their thermal expansion and dielectric properties were characterized. PPO/silica composites with the same volume fractions of silica were also prepared and characterized for comparison. With the content of filler increased from 0 to 30 vol%, the CTE of the PPO/ZWP composites reduced from 74.2 to 45.4 ppm/°C, which is more significant than that of the PPO/silica composites (48.0 ppm/°C with 30 vol% silica). Meanwhile, the dielectric loss of PPO/ZWP composites decreased significantly from 0.0024 (0 vol% ZWP) to 0.0018 (30 vol% ZWP) at 10 GHz, which is better than PPO/silica composites (0.0019 with 30 vol% Silica). The PPO/ZWP composites exhibit excellent comprehensive properties, which may be promising materials for high‐frequency applications in electronic packaging fields. [ABSTRACT FROM AUTHOR]

One challenge in the high‐performance dielectric material of polyimide (PI) is to obtain the excellent comprehensive properties at low curing temperature for advanced IC package. In this work, 6‐aminoquinoline (AQL) is introduced through covalent bonds for end capping to obtain a low‐temperature curable PI at first. The results demonstrate that with very limited introduce (2.76%) of AQL, the imidization index could reach as high as 1.01 at 200°C. Then, fluorinated nano carbon (FC) is further introduced resulting in the fluorinated nano carbon/polyimide (FCPI) composites, which effectively reduces the dielectric constant (1 wt%, 2.75 @ 1 MHz). Besides, the as‐prepared FCPIs also possess excellent thermal property of which FCPI‐0.3 exhibited the 5% weight loss temperature of 540°C and the glass transition temperature is also as high as 385°C. Furthermore, the tensile strength of the film is 127 MPa, the elongation at break is around 15.82%, and the Youngs' modulus is about 3.10 GPa proving the superior mechanical property. As a result, the successful preparation of the FCPI nanocomposites not only possess low‐temperature curing and low‐dielectric performance but also exhibit excellent thermal and mechanical properties, which shows a wide range of application prospects in the field of microelectronics for the advanced electronic package. [ABSTRACT FROM AUTHOR]

In this work, a novel thermal conductive and electrical insulation composite paper fabricated through doctor‐blading followed by hot‐pressing was reported. Specifically, by loading silver nanoparticles (AgNPs) on the surface of boron nitride nanosheets (BNNS) and silicon carbide wires (SiCw), the BNNS and SiCw were bridged through the sintered AgNPs to form a heat conduction path. The results indicate that the prepared composite paper not only enhances the thermal conductivity to 47 W m−1 k−1 but also possesses good mechanical properties and high electrical insulation. The optimizations can be attributed to the efficient BNNS/Ag/SiCw networks within the paper and strong interfacial combination through sintered AgNPs. Furthermore, the distribution and size of the AgNPs also affect the properties of the composites. This work provides a promising strategy to improve thermal conductivity of the composites by constructing efficient thermal conductive pathways, which are suitable for large‐scale preparation and have potential to be widely used in the field of electronic packaging. [ABSTRACT FROM AUTHOR]

In this research, the different weight percentages of alumina and graphene nanoplatelets were homogeneously dispersed in the epoxy resin by a sonication and ball milling mixing process. The effect alumina and graphene nanoplatelets filled epoxy nanocomposites of physical, flexural, and dynamic mechanical properties were investigated. The epoxy nanocomposites showed a significant enhancement of 43.5% flexural strength and 29.5% flexural modulus for the combined filler loading of 2 wt% of alumina and 0.5 wt% of graphene nanoplatelets sample (EA2G0.5) than the neat epoxy. The EA2G0.5 epoxy nanocomposites sample showed an enhancement of 68.1% for the storage modulus. The loss modulus peak shifts toward the right side than the neat epoxy, which is showing better thermal stability of the composite. The differential scanning calorimetry technique was used to study the curing characteristics of the epoxy and epoxy nanocomposites. The scanning electron microscopy images of a fractured surface of the neat epoxy and alumina and graphene nanoplatelets filled epoxy nanocomposites showed the dispersion of the fillers, which is the sole cause of the enhancement of flexural properties. In general, these developed nanocomposites are suitable to be used as parent material in electrical and electronic packaging applications. [ABSTRACT FROM AUTHOR]

Novel polymer‐based materials with highly thermally conductive and high‐mechanical properties have attracted extensive attention in the field of electronic packaging as thermal interface materials (TIMs), due to the development of electronic equipment to miniaturization and higher power density. However, how to achieve high‐thermal conductivity (exceed 5 W/m·K) with low‐filling content (below 30 vol%) is still the focus of attention. Herein, polymer‐based materials with excellent in‐plane thermal conductivity were prepared by a simple hot‐pressing strategy, and a series of nanocomposites with different orientations were controlled by the hot‐pressing times. As expected, compared with that of randomly dispersed 25 vol% BNNS/P(VDF‐HFP) nanocomposite and pristine P(VDF‐HFP), the in‐plane thermal conductivity of oriented 25 vol% BNNS/P(VDF‐HFP) is promoted by 249% and 3057%, respectively. In contrast to randomly dispersed composites, oriented BNNS/P(VDF‐HFP) at loadings above 10 vol% begin to show an encouraging upward trend. This is because the orientation of BNNS can significantly reduce the percolation threshold and construct an efficient heat conduction network under low‐filling volume. Therefore, this technology can provide new ideas for the development of electronic packaging technology. [ABSTRACT FROM AUTHOR]

Polymers are known as thermally insulated materials with reported effective thermal conductivity (Keff) in the range of 0.1 to 0.5 Wm−1 K−1. However, increasing demand for smaller and more powerful electronics has created the need for thermally conductive polymers for use in heat exchangers and electronic packaging applications. Given this background, much research has been done over the past two decades to increase the Keff of polymers. Based on the strategy involved, those works can be divided into two main categories: (i) increasing the Keff of the neat polymer by aligning its chains orientation; and (ii) increasing polymer Keff by fabrication of polymeric composites with thermally conductive filler networks. Among these two strategies, the former is limited to nanoscale laboratory research and is difficult to scale up for mass production. Therefore, this work is mainly focused on the latter category, thermally conductive polymeric composites, which has a higher potential for large‐scale production. This work aims to summarize, evaluate, and highlight the successful strategies of the recent efforts in enhancing the thermal conductivity of polymer composites. The major achievements, future challenges, and the outlooks of high thermally conductive polymeric composites are presented by analyzing the results of about 300 works. [ABSTRACT FROM AUTHOR]