Article
Engineering, Manufacturing
Sven Druecker, Hauke Voormann, Karl-Philipp von Berg, Maximilian Wilhelm Heinrich Ahrens, Valea Kim Wisniewski, Eike Schroeder, Andreas Kehne, Sonke Detjen, Simon Kaysser, Christian-Andre Keun, Bodo Fiedler
Summary: Material extrusion is commonly used in additive manufacturing but is mainly used for prototypes and simple jigs and fixtures due to anisotropic material behavior. In this study, a thermosetting polymer is developed to improve bonding between layers and infill lines during post-curing. The material formulation is also modified to add electrical conductivity for functional 3D printing.
ADDITIVE MANUFACTURING
(2022)
Article
Materials Science, Ceramics
ZhiJin Guo, WenBin Lu, Yan Zhang, JianPing Zhou, DaQian Sun
Summary: The addition of V2CTx two-dimensional materials in conductive adhesives increases the contact area between conductive particles, effectively reducing the resistivity of epoxy resin conductive adhesives. However, excessive content of V2CTx/Ag/rGO/MWCNTs can cause aggregation and increase the resistivity of the conductive adhesive. The volume resistivity of ECAs increases from 4.4 x 10-6 omega m to 1.15 x 10-5 omega m when the V2CTx/Ag/rGO/MWCNTs content increases from 0.1% to 0.34%. The interconnected Ag-clad Cu particles and V2CTx/Ag/rGO/MWCNTs form a larger conductive network inside the epoxy resin, resulting in good conductive properties of the adhesive.
CERAMICS INTERNATIONAL
(2023)
Article
Materials Science, Composites
Yanhong Ji, Peng Miao, Ruonan Zhang, Quan Li, Yifan Zha, Fengying Dai, Xi Du, Benqiao He, Shaoyun Fu
Summary: In this study, micro-sized flower-like silver particles (MFSPs) with long and thin petals are prepared by a novel chemical reduction method. The morphology and size of MFSPs are controlled by adjusting the reactant mass ratio and concentration. The as-prepared MFSP/epoxy composite adhesive exhibits low percolation threshold, high conductivity, and high adhesion strength at a very low silver content.
POLYMER COMPOSITES
(2022)
Article
Engineering, Chemical
Azadeh Mirabedini, Liam Anderson, Dennis Antiohos, Andrew Ang, Mostafa Nikzad, Franz Konstantin Fuss, Nishar Hameed
Summary: In this study, graphene nanoplatelets (GnP)-modified epoxy polymer nanocomposites with different concentrations were developed using two processing techniques. The results showed that ultrasonication enabled better exfoliation of graphene sheets, resulting in higher electrical conductivity at lower filler concentrations. Thermal conductivity, on the other hand, was mainly affected by the restacking of graphene sheets. Additionally, effective thermal and electrical conductivity models were defined to predict the performance of nanocomposites at different loadings. The optimized nanocomposite was successfully embedded into a carbon fiber laminate composite to enhance its properties.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2022)
Article
Materials Science, Composites
Dezhao Wang, Han Wei, Ying Lin, Pingkai Jiang, Hua Bao, Xingyi Huang
Summary: Polymer composites with super-high thermal conductivity can be achieved by combining microsilver and nanosilver fillers with MXene, resulting in a significant improvement in thermal conductivity. The bridging effect between silver particles and MXene flakes plays a key role in enhancing the thermal conductivity of the composites.
COMPOSITES SCIENCE AND TECHNOLOGY
(2021)
Article
Nanoscience & Nanotechnology
Shuo Wang, Hongqian Xue, Sherif Araby, Murat Demiral, Sensen Han, Can Cui, Rui Zhang, Qingshi Meng
Summary: Boron nitride nanosheets (BNNSs) were used to enhance both the mechanical and thermal properties of epoxy nanocomposites, resulting in significant improvements in thermal conductivity and mechanical performance, with potential applications in the electronic and automotive industry.
Article
Chemistry, Multidisciplinary
Huagao Wang, Rongjian Lu, Jia Yan, Jingsong Peng, Antoni P. Tomsia, Rui Liang, Guoxing Sun, Mingjie Liu, Lei Jiang, Qunfeng Cheng
Summary: Inspired by nacre, this study presents tough and conductive MXene/epoxy layered bulk nanocomposites with self-monitoring capability and excellent electromagnetic interference shielding efficiency. Surface chemical modification and annealing treatment improved the interfacial interactions and orientation of MXene lamellar scaffold. This research provides a new avenue for fabricating high-performance epoxy nanocomposites.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Materials Science, Multidisciplinary
David Santiago, Dailyn Guzman, Jesu's Padilla, Pere Verdugo, Silvia De la Flor, Angels Serra
Summary: Epoxy-based vitrimers with high Tg values and a homogeneous network structure were developed as recyclable and reprocessable adhesives for automotive structural applications. The materials showed complete stress relaxation in just 3.6 minutes at 180 degrees C, with the presence of TBD catalyst resulting in the fastest relaxation. They were successfully recycled and reprocessed through alcoholysis and mechanical grinding, and demonstrated high single-lap shear stress values for mono- and multimaterial joints. Overall, this study presents a comprehensive investigation of recyclable and reprocessable epoxy-based vitrimers.
ACS APPLIED POLYMER MATERIALS
(2023)
Article
Materials Science, Composites
Yuheng Huang, Tian Xia, Ian Kinloch, Cristina Valles
Summary: Novel out-of-autoclave (OoA) strategies were studied for repairing carbon fibre reinforced plastics (CFRPs) to simplify component maintenance and reduce unnecessary scrappage. Electrically conductive uncured nanocomposites with different graphene nanoplatelets (GNPs) loadings were used as adhesives to repair CFRPs through Joule heat curing. The lap shear strengths of the repaired CFRPs were comparable to those repaired using a conventional oven curing method, proving the effectiveness of this approach as an OoA repair method. Scanning electron microscopy revealed the coexistence of interfacial and cohesive failure mechanisms, with increased dominance of cohesive failure with higher GNPs loadings.
COMPOSITES SCIENCE AND TECHNOLOGY
(2023)
Article
Polymer Science
E. Yiyang, Zhaobo Tian, Keyu Chi, Renyao Jiang, You Lv, Qi Sun, Yuan Zhu
Summary: With the miniaturization of electronic devices, electronic packaging has become increasingly precise and complex, presenting a challenge in heat dissipation. This study proposes a method of treating silver epoxy adhesive with water vapor, resulting in a significant improvement in thermal conductivity. The introduction of H2O into the adhesive increases the path of electron conduction, improving thermal conductivity and offering potential for improving packaging material performance.
Article
Nanoscience & Nanotechnology
Hang Chi, Zewen Lin, Yuxin Chen, Renhao Zheng, Hong Qiu, Xiaolan Hu, Hua Bai
Summary: This paper reports on the direct ink writing 3D printing of multifunctional composite materials based on commercial epoxy resin and the recycling of printed composite materials. By adding graphene nanoplatelets as a thixotropic additive, the liquid epoxy resin can be shear-thinning and suitable for direct ink printing. The printed composite materials have high resolution, high mechanical strength, as well as high thermal and electrical conductivity, and fast thermo-induced shape memory response. The printed objects can be recycled by comminuting them into micropowders and used as a thixotropic agent for preparing recycled DIW ink.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Materials Science, Ceramics
WenBin Lu, Yan Zhang, JianPing Zhou, DaQian Sun, HongMei Li
Summary: In this study, conductive adhesives were prepared using Ag-coated Cu and V(2)C(T)x + Ag + MWCNTs + Ag composites as fillers. The effects of V2CTx + Ag + MWCNTs + Ag composites content on the conductivity and microstructural properties were investigated. The results showed that a high content of Ag-coated Cu and a low content of V(2)CTx + Ag + MWCNTs + Ag composites resulted in a conductive adhesive with low resistivity. The synergistic effect of Ag-coated Cu and V2CTx + Ag + MWCNTs + Ag composites improved the conductive properties of the epoxy resin adhesive.
CERAMICS INTERNATIONAL
(2023)
Article
Engineering, Chemical
Xiao Min Zhang, Xiao-Li Yang, Bin Wang
Summary: In this study, silver films were deposited on copper substrates to enhance oxidation resistance, and the resulting Ag/Cu powders were used as conductive fillers in ECAs. The research showed that ECAs could be chemically sintered at 150 degrees C for 30 minutes, resulting in excellent electrical conductivity.
INTERNATIONAL JOURNAL OF ADHESION AND ADHESIVES
(2021)
Review
Materials Science, Characterization & Testing
Seyed Rasoul Mousavi, Sara Estaji, Hediyeh Kiaei, Mohammad Mansourian-Tabaei, Sasan Nouranian, Seyed Hassan Jafari, Holger Ruckdaeschel, Mohammad Arjmand, Hossein Ali Khonakdar
Summary: This article provides an overview of the recent advances in research on improving the thermal and electrical conductivities of EP resin systems modified with CNT, Gr, their derivatives, and hybrids. Surface modification of these reinforcements is also discussed as a means to enhance the dispersion of nanofillers in EP resins.
Article
Engineering, Electrical & Electronic
Lekshmi Mohan, Sunitha Karakkad, Sindhu Thiruthi Krishnan
Summary: This study fabricates lightweight carbon nanotube-based epoxy nanocomposite shields with superior shielding effectiveness in both X and Ku frequency bands. The developed shields have promising potential as broadband shields with minimal thickness, less weight, and low cost.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2021)
Article
Polymer Science
Yuanzhang Jiang, Xuyi Wang, Yanting Han, Dakai Gong, Yingchun Gu, Lin Tan
Summary: In this study, FeCl3 and poly(acrylic acid) (PAA) were doped into waterborne polyurethanes (WPUs) to create multifunctional materials with self-healing and antimicrobial properties. WPU/Fe/PAA-5.5, containing 5.5 wt % PAA, exhibited excellent mechanical properties, strong self-healing capabilities, and an impressive antimicrobial rate of over 90%. These supramolecular films were also highly recyclable through hot-pressing.
Article
Polymer Science
Longyu Tian, Min Wang, Guangming Liao, Baoliang Liu, Sujuan Zhang, Yucheng Sun, Zhen Meng, Jintao Zhang, Zaijun Lu
Summary: Two kinds of benzoxazine monomers were synthesized and used to prepare polybenzoxazine anion exchange membranes (AEMs) with quaternary ammonium functionalization. The LQPBZ AEM exhibited better ion conductivity and alkaline stability.
Article
Polymer Science
Claire A. Lemarchand
Summary: This study investigates the shock behavior of three different polymers through molecular dynamics simulations. The results reveal specificities in the shock behavior of polymers, including deviations from the linear relation between shock velocity and particle velocity, as well as differences in shear stress relaxation behind the shock front. It is found that the deviation of the Hugoniot locus is related to the change in the relative contribution of bonding and non-bonding potential energies, while polymers with higher glass transition temperatures exhibit slower shear stress relaxation.
Article
Polymer Science
Zengquan Liu, Xiaochun Yin, He Zhang, Shuo Gao, Qinglin Kuang, Yanhong Feng
Summary: A powder solid-state extension (PSSE) technology was proposed to address the high melt viscosity issue of UHMWPE. By uniaxial extension and sintering in the solid state, a highly self-reinforced material was prepared. X-ray diffraction and scattering techniques were used to study the structural evolution during the PSSE process, and a solid-phase induced transformation model was established.
Article
Polymer Science
Zhike Li, Anyu Luo, Rui Zhou, Xin Li, Haiyan Li
Summary: A novel high temperature resistance IL@SiO2 nanocapsules were successfully prepared and their friction and wear properties in PA6 composites were studied. The addition of IL@SiO2 nanocapsules reduced the friction coefficient and wear rate without affecting the mechanical properties of PA6. The synergy between the IL core and SiO2 wall in the nanocapsules improved the self-lubricating performance of the PA6 composites.
Article
Polymer Science
Xin Liu, Xuhong Guo, Qi Liao
Summary: In this study, an algorithm for accurately estimating viscosity is developed using molecular dynamics simulations and the Green-Kubo formula. This algorithm can be applied to complex systems with long correlations, such as macromolecular and biological simulation systems.
Article
Polymer Science
Hao Pu, Yun-Lei Hou, Jing -Zhou Chen, Dong -Lin Zhao
Summary: The use of modified graphene improves the interfacial adherence of carbon fibers to epoxy resin, resulting in enhanced interfacial and bending properties of CF and matrix in CF/EP composites, as well as increased interlaminar shear strength and flexural strength.
Article
Polymer Science
Wei-Chung Ke, Jin-Wei Lin, Manohar Reddy Busireddy, Yueh-Hsing Lee, Jiun-Tai Chen, Chain-Shu Hsu
Summary: This study introduces a crosslinkable monomer, TAIC, to synthesize three crosslinked polyimide films, which exhibit improved thermal, mechanical, and dielectric properties. The introduction of TAIC enhances the tensile strength, reduces the dielectric constant and dielectric loss, and decreases the coefficient of thermal expansion of the polyimide films.
Article
Polymer Science
Alex Kwasi Kumi, Ruiling Fan, Ye Chen, Yumei Zhang
Summary: The difference in leaching of amylopectin from cellulose/amylopectin/1-butyl-3-methylimidazolium chloride ([Bmim][Cl]) blends during regeneration in water and aqueous ethanol has been studied. Molecular dynamics simulations showed that the dissolution and regeneration mechanisms of amylopectin in [Bmim][Cl] are similar to cellulose in ionic liquids. Water regeneration leads to weak electrostatic interactions, resulting in high leaching of amylopectin. In contrast, ethanol-water interactions enhance electrostatic interactions among amylopectin chains, limiting amylopectin leaching in aqueous ethanol.
Article
Polymer Science
Xi Zeng, Junwei Zhou, Junbiao Peng, Chunsheng Zhang, Danling Wang, Yihu Song, Qiang Zheng
Summary: This study utilizes an oligomer deep eutectic solvent (DES) based on polyethylene glycol to regulate the vulcanization kinetics of rubber. The results show that the DES can accelerate vulcanization at low temperatures without affecting the crosslinking density and Mullins effect.
Article
Polymer Science
Qianqian Yue, Yongfei Peng, Xingjian Liu, Aihua He, Huarong Nie
Summary: The addition of metal deactivators can effectively suppress the aging of TBIR, prolong its lifespan, and have no negative effects on its physical and processing properties. These research findings are of great importance for improving the stability and aging resistance of polymers.
Article
Polymer Science
J. Gomez-Caturla, J. Ivorra-Martinez, R. Tejada-Oliveros, V Moreno, D. Garcia-Garcia, R. Balart
Summary: This work focuses on the development of environmentally friendly PLA formulations by using different esters derived from geraniol as plasticizers. The results show that these esters have good compatibility with PLA, and they can effectively enhance the elongation and plasticity of PLA, reduce its glass transition temperature, and slightly improve its water absorption capabilities.
Article
Polymer Science
Dandan Li, Zhaohui Lu, Zhao Ke, Ke Xu, Fengna Dai, Youhai Yu, Guangtao Qian, Chunhai Chen
Summary: In this study, cross-linked PI aerogel membranes with low dielectric constant and high moisture resistance were prepared by co-polymerization and scraping coating technology. The incorporation of fluorinated blocks and benzimidazole ring structures resulted in novel PI aerogel membranes with fascinating dielectric properties and outstanding moisture resistance.
Article
Polymer Science
Zhaoyang Chu, Qing Zhang, Haihua Luo, Han Zhou, Fapei Zhang, Wei Chen, Wenhua Zhang
Summary: Multi-physical fields solution processing strategy is a universal and facile method for preparing various conjugated polymer films and high-performance devices. In this study, we employed a combined microfluidic flow and ultrasonication strategy (FU) for processing CP solutions, and found a pronounced synergetic effect in promoting the pre-ordering of chains in solution. The conformation order and anisotropy of the solution were revealed through various characterizations. A non-classical nucleation model for polymer crystallization in non-equilibrium solution processing was confirmed. The roles of microfluidic flow and ultrasonication in chain aggregation and crystallization were addressed through multi-physical simulations. Compared to pristine solutions, the FU strategy showed improved solution anisotropy and crystallization kinetics, resulting in higher crystallinity in films and increased mobilities in OFET devices. The FU processing strategy provides a universal approach for regulating chain conformation and aggregation in conjugated polymer solutions.