Article
Materials Science, Multidisciplinary
Zhiqiang Chen, Chenyu Jin, Zhen Li, Xiuzhao Li, Liuyu Yang, Tiejun Wang
Summary: Progress in vitrimer chemistry enables the production of reprocessable thermosets, but the conflict between mechanical performance and dynamic reactivity hinders its industrial applications. In this study, a universal material design strategy is proposed to create tough epoxy vitrimers with excellent reprocessability. By copolymerization and bond exchange reactions, a hybrid dynamic covalent polymer network containing hard and soft segments is formed. Controllable mechanical and thermal properties are achieved by adjusting the ratio of hard-to-soft components. The resulting epoxy vitrimer exhibits a balance between strength and stretchability and improved fracture toughness compared to pristine vitrimers. It also shows great potential in various applications such as composite fabrication, welding, reshaping, and shape memory functions.
ADVANCED ENGINEERING MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Zi-Han Zhao, Pei-Chen Zhao, Shi-Yi Chen, You-Xuan Zheng, Jing-Lin Zuo, Cheng-Hui Li
Summary: This study incorporates dynamic covalent boronic ester linkages with internal B-N coordination into a commercial epoxy matrix to prepare room-temperature phosphorescence (RTP) polymers. The obtained polymers show enhanced mechanical toughness, ultralong RTP, shape memory behavior, and excellent durability in various solvents. These novel properties make them suitable for potential applications in information encryption and anti-counterfeiting.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Materials Science, Multidisciplinary
Sijia Ren, Jiachun Feng
Summary: In this study, reconfigurable and reprocessable thermadapt two-way shape memory polymers (2W-SMPs) were synthesized using polyethylene glycol and hydroxylated modified SBS through dynamic covalent bonding. The 2W-SMPs exhibit a good balance of mechanical properties and a favorable two-way shape memory effect (2W-SME) with a reversible actuation strain of 11.9%. These materials can be reprocessed and transformed into complex 3D shapes due to the dynamic covalent exchange and reversible physical crosslinking. Furthermore, a biomimetic mimosa actuator that can undergo shape changes through finger contact and cooling was manufactured. This study provides a new idea for the development of thermadapt 2W-SMPs and shows great potential applications in intelligent actuators.
ADVANCED MATERIALS TECHNOLOGIES
(2023)
Article
Engineering, Environmental
Liang Jiang, Yuan Lei, Yao Xiao, Hualiang Xu, Anqian Yuan, Zhengkai Wei, Yue Chen, Jingxin Lei
Summary: By embedding carbon black into thermoset polyurea matrix and utilizing commodity raw materials, a series of dynamic thermoset polyurea composites were designed, exhibiting outstanding mechanical properties and reprocessability. The fusion of carbon black conductivity and urea bond dynamics in these materials not only provides traditional elastic shape memory performance, but also enables plastic shape memory and permanent shape reconfiguration.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Engineering, Environmental
Jinshuai Zhang, Chaoqun Zhang, Fei Song, Qianqian Shang, Yun Hu, Puyou Jia, Chengguo Liu, Lihong Hu, Guoqiang Zhu, Jia Huang, Yonghong Zhou
Summary: This study presents a method of preparing multifunctional biobased polyurethane materials using hindered urea bonds (HUBs). These materials exhibit extremely low relaxation times, excellent scratch healing efficiency, recyclability, and good adhesion strength, while also demonstrating shape memory behavior.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Polymer Science
Bingjie Zhao, Honggang Mei, Guohua Hang, Lei Li, Sixun Zheng
Summary: A novel organic-inorganic polyurethane thermoset crosslinked with a difunctional polyhedral oligomeric silsesquioxanes (POSS) was synthesized via Diels-Alder (DA) reaction. The resulting DAPU-DDSQs displayed improved thermomechanical properties and shape memory properties with increasing 3,13-dimaleimido DDSQ incorporation. The reprocessing properties of the DAPU-DDSQs at the temperature of retro DA reaction allow for the re-editing of the original shapes of shape memory PUs.
Article
Polymer Science
Xianjie Pan, Jiawei Li, Fanqi Liu, Chaoying Hu, Yanning Zeng
Summary: In this study, a series of versatile, self-healable, weldable, and recyclable castor oil-based poly(thiourethane-urethane) networks were constructed through one-pot reactions. The obtained networks showed high thermostability and excellent functions in self-healing, welding, shape memory, and reprocessing capabilities at moderate temperatures due to the dynamic boronic ester bonds.
JOURNAL OF APPLIED POLYMER SCIENCE
(2023)
Article
Chemistry, Physical
Reza Lashkari, Sara Zare, Seyyed Alireza Tabatabaei-Nezhad, Maen M. Husein
Summary: This study evaluated the application of reprocessable smart shape memory polyurethane (SMPU) lost circulation materials (LCMs) based on SMPU silica nanocomposite in geothermal drilling. The results showed that the chemically integrated silica nanoparticles effectively reinforced the SMPU matrix and improved the dispersion of the silica nanoparticles. Compared to commercial mica LCMs, the modified silica nanocomposite SMPU LCMs demonstrated higher sealing capability and lower fluid loss in their third cycle, enhancing drilling procedure safety and environmental protection.
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
(2023)
Article
Polymer Science
Xiao Wang, Linlin Wang, Xuexuan Fan, Jiaqi Guo, Lei Li, Shengyu Feng
Summary: By incorporating supramolecular motifs into polysiloxanes, a novel coordinative polysiloxane functionalized with 2-hydroxy-1-naphthyl imine group has been designed and synthesized, showing remarkable ion recognition ability, preparation of supramolecular elastomers, and development of reprocessable shape-memory materials. This new type of polymer could pave the way for wider applications of supramolecular polysiloxane materials.
Article
Chemistry, Multidisciplinary
Fang-Zhou Wang, Hong-Qin Wang, Wen-Tong Gao, Cheng-Hui Li
Summary: The stiff polyurea described in the study has high mechanical strength and can be reprocessed and healed under mild conditions. It demonstrates a small energy barrier for bond exchange and high kinetics speed constant, which are attributed to the high reactivity and steric hindrance of piperazine groups. These properties make it attractive for sustainable industrial applications.
MATERIALS CHEMISTRY FRONTIERS
(2022)
Review
Construction & Building Technology
Iman Abavisani, Omid Rezaifar, Ali Kheyroddin
Summary: Shape memory materials (SMMs) are widely used in civil engineering due to their unique ability to memorize their original shape and return to it under stimuli. These materials, including shape memory alloys, magnetic shape memory alloys, shape memory polymers, and shape memory ceramics, have multifunctional properties and can be applied in various systems.
JOURNAL OF BUILDING ENGINEERING
(2021)
Article
Polymer Science
Weiming Xu, Yi Pan, Lv Yin, Zhaohui Zheng, Jinni Deng, Xiaobin Ding
Summary: A reprocessable shape memory epoxy resin based on substituent diphenyl structure was successfully synthesized in this study, showing excellent shape recovery properties and good repeatability. This resin provides a feasible approach to improve the performance of shape memory epoxy resin, maintaining good shape recovery ability even after reprocessing.
MACROMOLECULAR CHEMISTRY AND PHYSICS
(2021)
Article
Engineering, Biomedical
Ailifeire Fulati, Koichiro Uto, Masanobu Iwanaga, Miho Watanabe, Mitsuhiro Ebara
Summary: This article reports a novel shape-memory polymeric string that is ultra-stretchable, strong, tough, and highly recoverable. The contraction force of this string can be customized by adjusting the energy storage capacity, and it displays a controllable shape-memory response time. It has potential applications in blood vessel contraction in minimally invasive surgeries.
ADVANCED HEALTHCARE MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Xingjian Li, Lele Wang, Yinwen Li, Shoufang Xu
Summary: Here, a self-healing, reprocessable, and thermadapt polycaprolactone (PCL)-based shape memory polymer has been achieved through robust ester-ester interchange catalyzed by dibutyltin dilaurate (DBTDL). The polymer system is fabricated by the common free-radical polymerization of PCL diacrylate, which is straightforward and highly reproducible. DBTDL acts as a stable, efficient, oxidation-resistant, and nonstaining catalyst system for the ester-ester interchange.
ACS APPLIED POLYMER MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Xingjian Li, Lele Wang, Yinwen Li, Shoufang Xu
Summary: A self-healing, reprocessable, and thermadapt polycaprolactone (PCL)-based shape memory polymer was reported, with efficient ester-ester interchange catalyzed by dibutyltin dilaurate (DBTDL). The polymer was fabricated through free-radical polymerization of PCL diacrylate, showing excellent reproducibility. The ester-ester dynamic exchanges in the polymer system enabled the achievement of a PCL shape memory polymer with self-healing, reconfigurability, and reprocessability.
ACS APPLIED POLYMER MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Zhenyu Zhao, Weimin Huang, Hua Qin, La Li
Summary: This work experimentally investigates and compares the terahertz electromagnetic shielding effect of micrometer-thick Ti3C2Tx MXene films on polyimide prepared by two different etching methods. The process using HCl/HF as the etchant shows higher absorption coefficient and electrical conductivity. Raman spectroscopy and scanning electron microscopy are used to study the structure and termination of the Ti3C2Tx MXene layer. The degree of oxygen termination plays a significant role in bridging nearby titanium atoms, resulting in increased surface continuity and enhanced terahertz radiation shielding.
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
(2023)
Article
Engineering, Biomedical
Xin Wang, Qiong Tian, Mingxing Zhu, Yingying Wang, Boya Wang, Xiaobei Jing, Hiroshi Yokoi, Lin Li, Zhenzhen Liu, Weimin Huang, Shixiong Chen, Zhiyuan Liu, Guanglin Li
Summary: Long-term physiological signal monitoring is crucial for diagnosing health conditions that occur randomly and are not easily detected during short hospital visits. However, the quality of signals obtained by conventional wet electrodes degrades over time due to gradual dehydration. This study proposes the use of an anhydrous carbon paste electrode (CPE) composed of carbon black and polydimethylsiloxane to enable long-term monitoring without signal quality degradation. Compared to wet electrodes, the CPE showed more stable skin-electrode impedance and higher signal qualities for ECG, EMG, EEG, and ABR measurements over a period of 48 days.
IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING
(2023)
Article
Chemistry, Physical
Daiqing Zhu, Yihong Zhang, Weipeng Xuan, Jinkai Chen, Miling Zhang, Jikai Zhang, Hao Jin, Shurong Dong, Jikui Luo
Summary: This work focuses on the development of Pt-Rh alloy-based multilayered composite IDTs for high-temperature applications. The composite electrodes were prepared by magnetron sputtering, and their resistance and surface morphology were investigated at temperatures up to 1600 degrees C. The results showed that the composite electrodes could withstand a maximum operating temperature of 1600 degrees C in air.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Materials Science, Multidisciplinary
Chunjian Su, Xuemeng Li, Zhengyang Feng, Xinxin Li, Balasundaram Selvan Naveen, Luhua Zhao, Weimin Huang
Summary: In this paper, a bending angle distribution function with optimized segmented boundary combination is proposed to improve the forming quality and reduce rebound defects in multi-pass roll forming. The stress and strain distributions in the sheets after each forming pass are analyzed using finite element simulation, and the influence of different bending angle parameters on sheet quality is obtained. The finite element simulation is verified by comparing experimental results.
MATERIALS & DESIGN
(2023)
Article
Materials Science, Textiles
Durai Aadithiya, Fei Yu Fang, Han Wang, Wei Min Huang
Summary: In this paper, finite element simulation (via ANSYS) is used to investigate the effect of shell thickness and prestrain on stimulus-induced shrinkage in electrospun polymeric fibres. The results show that the maximum shrinkage is determined by the prestrain in the shell. Young's modulus, fibre length, and boundary conditions have little influence on the final relative axial shrinkage. The diameter of the electrospun fibres strongly affects the final relative axial shrinkage, suggesting its potential for determining shell thickness and prestrain experimentally.
FIBERS AND POLYMERS
(2023)
Article
Engineering, Electrical & Electronic
Meiwen Ding, Zhiping Lin, Chau Hung Lee, Cher Heng Tan, Weimin Huang
Summary: Prostate cancer is a common malignant tumor in men, and magnetic resonance imaging (MRI) is an important tool for its diagnosis. Accurate diagnosis requires targeted biopsy, often aided by MRI-ultrasound (MRI-US) fusion. However, automatic prostate segmentation on MRI is challenging due to variations in shape, appearance, and size. In this study, we propose a method called UCAnet that incorporates multi-scale and Channel-wise Self-Attention (CSA) to improve prostate segmentation accuracy. Experimental results on a public dataset demonstrate that UCAnet outperforms state-of-the-art methods for prostate segmentation.
IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS II-EXPRESS BRIEFS
(2023)
Article
Chemistry, Physical
Haobin Wang, Shuyi Huang, Haoze Kuang, Chi Zhang, Yulu Liu, Kaihang Zhang, Xinyu Cai, Xiaozhi Wang, Jikui Luo, Zhong Lin Wang
Summary: Triboelectrification between metals, polymers, and semiconductors was investigated, revealing a universal mechanism involving both electrostatic induction and dynamic junction modulation. The outputs of triboelectrification exhibited four current/voltage peaks, two of which were attributed to electrostatic induction effects and determined by surface state densities and electron affinity differences between the materials. The other two peaks were associated with dynamic junction modulation effects and determined by charging exchange between surface states and depletion regions. While metals and polymers showed no modulation of depletion regions, only the peaks induced by electrostatic induction were observable. Semiconductors, on the other hand, exhibited additional peaks induced by junction modulation when in contact with any material type. These findings provide valuable insights for developing high-performance triboelectric nanogenerators.
ADVANCED ENERGY MATERIALS
(2023)
Article
Chemistry, Physical
Shimna Shafeek, Neethu T. M. Balakrishnan, Bushara Fatma, Ashish Garg, M. J. Jabeen Fatima, Danny Morton, Jikui Luo, Prasanth Raghavan
Summary: This research conducts a comprehensive analysis on a novel nanocomposite of polyvinylidene fluoride (PVDF)/silicon car-bide (SiC) nanoparticles as a triboelectric material, and fabricates triboelectric nanogenerators (TENG) using the SiC-PVDF nanocomposite and polyamide (PA6) membrane combination. The results show that the inclusion of SiC nanoparticles greatly enhances the beta-phase content of the PVDF films and increases surface roughness and porosity of the SiC-PVDF nano-composites. The TENG made with a PVDF film with 6 wt% of SiC exhibits high-power output, which is four times higher than that of the TENG using the film prepared using the solution casting method.
Article
Nanoscience & Nanotechnology
Jiafeng Ni, Weipeng Xuan, Yilin Li, Jinkai Chen, Wenjun Li, Zhen Cao, Shurong Dong, Hao Jin, Lingling Sun, Jikui Luo
Summary: A high-flowrate and high-pressure load valveless piezoelectric micropump with dimensions of 16mm*16mm*5mm is proposed for wearable/portable applications, especially for blood pressure monitoring. The performance of the micropump is promising with a high flowrate and pressure load.
MICROSYSTEMS & NANOENGINEERING
(2023)
Article
Medicine, General & Internal
Shengming Wang, Luoqi Yang, Haofei Jiang, Jie Xia, Wenjuan Li, Zujuan Zhang, Shaomin Zhang, Hao Jin, Jikui Luo, Shurong Dong, Yanlan Yu, Zhenwei Xie
Summary: Pelvic floor dysfunction (PFD) is a serious public health problem. The lack of reliable diagnostic devices hinders accurate evaluation and diagnosis of regional pelvic floor muscle (PFM) malfunctions. In this study, a multifunctional evaluation technology (MET) was developed using an innovative airbag-type stretchable electrode array probe (ASEA) for diagnosing PFM malfunctions. Clinical trials using the MET showed that it can accurately diagnose regional PFM malfunctions and evaluate inter-regional correlation. The MET provides a potential point-of-care diagnostic method for targeted electrical stimulation treatment and PFD pathology research.
Article
Multidisciplinary Sciences
Dandan Wang, ZiZhang Li, Weimin Huang, Shengnan Cao, Liangyu Xie, Yuanzhen Chen, Huazhong Li, Lei Wang, Xiaoshu Chen, Jian-Rong Yang
Summary: Using single-cell RNA sequencing, the microenvironment and mechanisms of intervertebral disc degeneration (IVDD) in humans were explored. Functional subgroups were identified in the nucleus pulposus (NP) and annulus fibrosus (AF) at different stages of degeneration. Additionally, an increase in monocyte/macrophage population was found in degenerated discs, and specific interactions between cell populations were revealed.
Article
Chemistry, Analytical
Shaokui Wang, Weipeng Xuan, Ding Chen, Yexin Gu, Fuhai Liu, Jinkai Chen, Shudong Xia, Shurong Dong, Jikui Luo
Summary: Sleep apnea syndrome (SAS) is a common health problem that is often undiagnosed, affecting quality of life and increasing cardiovascular risks. To address the complicated and expensive clinical diagnosis procedures for sleep apnea, a small and low-cost wearable apnea diagnostic system is proposed. The system utilizes a photoplethysmography (PPG) optical sensor to collect pulse wave signals and blood oxygen saturation synchronously, and uses algorithms to process the signals for analysis and diagnosis with a high accuracy of over 85%.
Article
Automation & Control Systems
Chunjian Su, Xinxin Li, Xuemeng Li, Zhengyang Feng, Balasundaram Selvan Naveen, Rui Wang, Wei Min Huang
Summary: In the sheet forming process, the final bending angle is often determined based on experience and it is difficult to control the quality of the final products due to the decrease in thickness in the local bent areas. This study developed an optimized bending angle function by combining segment boundaries to improve the sheet forming quality and reduce local thinning defects. The finite element submodel method accurately simulated the thickness variation law of the bending area and analyzed the process parameters for local thinning. Experimental results showed that the proposed approach achieved better forming quality with smaller thinning defects compared to previously reported methods, and the thickness of the thinning defect was influenced by the process parameters and plate thickness.
INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
(2023)
Article
Chemistry, Analytical
Yubo Li, Jiadong He, Cangcang Fu, Ke Jiang, Junjie Cao, Bing Wei, Xiaozhi Wang, Jikui Luo, Weize Xu, Jihua Zhu
Summary: Pain management is crucial in medicine, especially for children who struggle to communicate their pain effectively. This paper presents a pain assessment scheme based on skin potential signals, aiming to provide objective pain identification using machine learning methods. Experimental data from 623 subjects were analyzed, and 358 valid records were selected. Seven features showed superior performance in pain identification, with the random forest algorithm achieving the highest accuracy of 70.63%. While our results differ from previous research, our pain assessment scheme demonstrates significant potential in clinical settings.
Article
Chemistry, Analytical
Zhiheng Zhang, Weipeng Xuan, Hong Jiang, Weilun Xie, Zhaoling Li, Shurong Dong, Hao Jin, Jikui Luo
Summary: This work proposes a longitudinally excited shear-wave resonator (YBAR) based on single-crystalline lithium tantalate (LiTaO3, LT) thin film, which achieves high effective electromechanical coupling and spurious-free response with the help of an optimized Bragg reflector. This solution has the potential to enable high coupling micro-acoustic resonators with a high Q factor in the 5G/6G communication system.
