Review
Materials Science, Composites
Sithara Gopinath, Nayarassery N. Adarsh, P. Radhakrishnan Nair, Suresh Mathew
Summary: Shape memory polymers (SMPs) are stimuli-responsive polymers that can recover their initial shape under external stimuli. They have wide applications in various fields due to their unique features and the integration of nanofillers can further enhance their properties, forming shape-memory polymer nanocomposites (SMPNCs). This review focuses on thermo-responsive SMPs, discussing their design, classifications, and the characteristics of elastomers and polymer blends used. It also discusses the importance of T-g and T-m based SMPs and SMPNCs, various elastomers used, preparation methods, and future applications.
POLYMER COMPOSITES
(2023)
Article
Polymer Science
Subhan Salaeh, Sujitra Nobnop, Bencha Thongnuanchan, Amit Das, Sven Wiessner
Summary: This study proposes a facile and new approach using graft copolymerization and amidation reaction to prepare shape memory polymer based on natural rubber. The novel cross-linked MGNR with a three-dimensional network of amide linkage shows improved solvent resistance, mechanical properties, and phase morphology. The cross-linked MGNR40 exhibits excellent shape fixation and shape recovery, which is attributed to the vitrification of the grafted PMMA domains at low temperatures and the recovery force from the cross-linked network.
Review
Optics
Chaoping Wei, Xuegang Lu, Xiaoxiang Wen, Yuting Liu, Sen Yang
Summary: Structural colors derived from nature have unique optical performances and various applications. Tunable structural colors have been realized through the development of biomimetic micro/nanostructures. Functional materials utilizing thermal polymer and photonic microstructure have broad application prospects in sensor, display, anti-counterfeiting and biomedical treatments.
OPTICS AND LASER TECHNOLOGY
(2022)
Article
Polymer Science
Sisi Chen, Mengyao Zhang, Qingyuan Li, Jiachen Li, Shengpeng Wu, Jian Zhou, Guoqing Jin, Zhengbiao Zhang, Xiangqiang Pan, Jian Zhu
Summary: Liquid crystal elastomers (LCEs) are versatile polymer materials used in various applications, but the contradiction between reprogrammability and stable actuation performance remains a challenge. Introducing photoactivated dynamic covalent bonds (DCBs) into thermotropic LCEs can help address this issue. This study utilizes allyl selenide chemistry to achieve multiple network reconfigurations of LCEs under visible light conditions (405-450nm). The mild stimulation conditions and sustainable dynamic exchange capability offer great potential for the application and design of covalently adaptable LCEs.
Article
Polymer Science
Xiaoyu Guan, Hong Xia, Qing-Qing Ni
Summary: Electrospun nanofibrous yarns based on shape memory polyurethane (SMPU) were successfully prepared, with the 60 degrees twisted yarn showing improved mechanical properties and shape memory recovery stress compared to non-twisted SMPU nanofibers. This yarn also demonstrated a high load-bearing capacity and potential applications in the medical and biological fields as actuators and sensors.
JOURNAL OF APPLIED POLYMER SCIENCE
(2021)
Article
Instruments & Instrumentation
Xiaodong Wang
Summary: Thermochemically responsive shape memory polymers (SMPs) have attracted great interest in biomedical applications. This study investigates the effects of temperature and solvent absorption on conformational rearrangements in SMPs using a proposed model. The results are compared with experimental data, and a good agreement is achieved. This model is expected to provide theoretical guidance for understanding the working mechanism of thermochemically responsive SMPs and advancing their engineering applications.
SMART MATERIALS AND STRUCTURES
(2022)
Article
Polymer Science
Emre Tekay
Summary: Thermally-triggered shape memory polymers (SMPs) can change shape when exposed to heat. Blending PEO and SIS thermoplastic elastomers resulted in a 60PEO/40SIS blend with the best shape memory performance, showing 95.74% shape fixing and 98.98% shape recovery. The presence of semi-crystalline PEO improved shape fixing, while SIS content enhanced shape recovery capability, despite the immiscibility of these polymers.
POLYMERS FOR ADVANCED TECHNOLOGIES
(2021)
Article
Instruments & Instrumentation
Jian Li, Zhihong Liang, Junjie Liu, Chao Yu, Xuelian Zhang, Qianhua Kan
Summary: The cyclic shape memory effect of thermo-induced shape memory polymers can be influenced by thermo-mechanical loading histories. During deformation, polymer chains undergo the initial dissociation of sub-entanglements, slipping, and orientation. The strain can be recovered through the internal rotation of the dihedral angle during reheating. A thermo-viscoelastic model is proposed to capture the cyclic shape memory effect, considering the slipping of polymer chains and the relationship between strain and orientation. The model is verified through experimental and simulated results, showing reasonable predictions of the cyclic shape memory effect.
SMART MATERIALS AND STRUCTURES
(2023)
Article
Instruments & Instrumentation
Yuta Suzuki, Qichan Hu, Benjamin Batchelor, Walter Voit, Melanie Ecker
Summary: Thiol-ene/acrylate shape memory polymers (SMPs) have been developed as substrates for flexible bioelectronic devices, thanks to their stiffness for easy insertion and softening under physiological conditions. In this study, a new class of SMPs was designed by introducing dopamine acrylamide (DAc) as a hydrophilic monomer, demonstrating improved softening and shape recovery properties under physiological conditions. This strategy enhances the performance of SMPs without sacrificing stiffness at room temperature.
SMART MATERIALS AND STRUCTURES
(2023)
Article
Chemistry, Physical
Zhenzhen Wei, Luyang Yu, Shuqing Lu, Yan Zhao
Summary: This article summarizes the application of reversibly thermo-responsive materials in lithium batteries, which can autonomously detect and respond to thermal faults in the battery, improving its thermal safety and durability. Firstly, the authors review four types of different thermoresponsive materials, including sol-gel transition polymers, phase change materials, temperature-stimulus shape memory materials, and positive temperature coefficient thermosensitive materials. Secondly, they summarize how these materials couple with lithium battery components and are applied in external management of batteries to enhance safety and electrochemical performance. Finally, they propose ideas for new applications and future development of thermo-responsive materials in the field of lithium batteries.
ENERGY STORAGE MATERIALS
(2023)
Article
Materials Science, Characterization & Testing
Kyung Hee Kang, Young-Wook Chang, Mohammad Sabzi
Summary: In this study, multi-stimuli responsive nanocomposites with recyclability and rapid healability features were developed by incorporating thermo-reversible DA bonds and functionalized reduced graphene oxide (f-rGO) into ethylene copolymer (G-PE). The results showed significant improvement in mechanical properties of the matrix with loading a low amount of f-rGO, and the re-workability of the developed materials with no significant differences in their mechanical properties after melt-reprocessing. Scratch-healing and shape recovery were also observed under direct heating and near infrared light for the nanocomposites.
Article
Nanoscience & Nanotechnology
Dan Li, Chengzhi Zhou, Yun Meng, Chao Chen, Chengjiao Yu, Yi Long, Shuzhou Li
Summary: Thermo-responsive smart windows with a deformable surface morphology can achieve desired solar modulation and luminous transmission based on different sunlight incident angles. This design provides a new mechanism for thermo-responsive smart windows.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Polymer Science
Yanmei Wang, Juan Zhang, Mingyang Li, Mingju Lei, Yanen Wang, Qinghua Wei
Summary: This study focuses on the 3D printing performance and shape memory properties of thermoplastic polyurethane and polycaprolactone blends. The results show that 3D printing does not affect the thermal properties, but an increasing TPU content in the blends leads to a decrease in tensile strength.
JOURNAL OF POLYMER RESEARCH
(2022)
Article
Polymer Science
Justinas Jaras, Aukse Navaruckiene, Edvinas Skliutas, Jurga Jersovaite, Mangirdas Malinauskas, Jolita Ostrauskaite
Summary: Novel thermo-responsive shape-memory vanillin-based photopolymers have been developed with excellent shape-memory properties, able to maintain temporary shapes on non-flat surfaces. By adjusting the ratio of monomers to tune the reaction mechanisms, a wide range of thermal and mechanical properties of the photopolymers was achieved.
Article
Polymer Science
Wenqiang Yan, Yun Ding, Run Zhang, Xinjie Luo, Pinghou Sheng, Ping Xue, Jimin He
Summary: Tunable thermo-responsive shape memory and self-healing bifunctional blends are fabricated by melt blending of poly(ethylene-co-methacrylic acid sodium salt) (EMNa) and poly(ethylene-comethyl acrylate) (EMA) copolymers. The blends exhibit rapid shape recovery, repeatable self-healing capability, and superior mechanical strength, making them promising in various cutting-edge applications.
Article
Chemistry, Applied
Yuntao Liu, Weimin Huang, Changyi Zhang, Cheng Li, Zhengfeng Fang, Zhen Zeng, Bin Hu, Hong Chen, Wenjuan Wu, Tiqiang Wang, Xiguo Lan
Summary: This study evaluated the metabolic profiles and biological activity of four Tibetan teas and found significant differences in their metabolic profiles, providing important data for quality detection of Tibetan tea.
Article
Engineering, Manufacturing
Abhijit Vijay Salvekar, Faqrul Hasif Bin Abdul Nasir, Ya Hui Chen, Sharanya Maiti, Vivek Damodar Ranjan, Hong Mei Chen, Han Wang, Wei Min Huang
Summary: This study demonstrates the feasibility of rapid volumetric additive manufacturing in the solid state. This technology is particularly useful for missions in outer space or in harsh environments. By using a special thermal gel, the concept of solid-state ultraviolet crosslinking is demonstrated, and the water-content-dependent heating/cooling/water-responsive shape memory effect of hydrogels is revealed. The shape memory feature is important for eliminating deformation during the last step of the additive manufacturing process when removing the uncrosslinked part.
3D PRINTING AND ADDITIVE MANUFACTURING
(2022)
Article
Chemistry, Physical
Ayush Prasad, Wei Min Huang
Summary: This study analyzes the surface patterns created on a shape memory polymer after indentation, polishing, and recovery through the shape memory effect. Different patterns, including lens-type protrusion, flat-top protrusion, and groove, are determined by the polishing depth and friction coefficient. The findings can be scaled and applied to other shape memory polymers.
SURFACE REVIEW AND LETTERS
(2022)
Article
Polymer Science
Changchun Wang, Jia Xi Pek, Hong Mei Chen, Wei Min Huang
Summary: This study investigates the influence of temperature and strain on the toughness of dog-bone shaped poly(methyl methacrylate) (PMMA) samples through pre-stretching, and reveals the impact of aging on the sample properties.
Article
Chemistry, Physical
Guoqiang Cao, Yue Xiao, Wei-Min Huang, Chien-Hua Chen, Jonas Baltrusaitis
Summary: This study investigates the production of hydrogen (H2) through ethanol steam reforming (ESR) in a dielectric barrier discharge (DBD) plasma reactor. A response surface methodology (RSM) was used to evaluate the effects of discharge power, total flow rate, and ethanol-to-water (EtOH/H2O) molar ratio on the plasma-assisted ESR reaction. The results showed that the EtOH/H2O molar ratio had the most significant effect on EtOH conversion and H2 selectivity, while the total flow rate determined the specific energy requirement (SER) for H2 production. Process optimization resulted in the identification of the optimal conditions for the ESR reaction.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Polymer Science
Xuelian Wu, Jiaxing Zou, Jian Yang, Jiang Jiang, Qin Feng, Zihao Ye, Weimin Huang
Summary: Electrically conductive IPN composed of PVC and PANI is achieved with slightly different mechanical and shape memory properties compared to PVC alone. Non-uniform distribution of PANI in the thickness direction is observed. Heating and programming lead to a reduction in electrical conductivity, with further decrease during shape recovery.
JOURNAL OF APPLIED POLYMER SCIENCE
(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
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
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
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
Materials Science, Biomaterials
Jia Wang, Cheng Li, Wei Zhang, Weimin Huang, Zhiqiang Liu, Rui Shi, Shiyuan Wang, Shan Liu, Weiguo Shi, Yunlan Li, Liang Xu
Summary: This paper proposes a new hemostatic powder based on poly(ethylene glycol)-di(cyanoacrylate) (CA-PEG-CA), which has tissue-contact-triggered strong adhesion and controlled fast degradation. The powder quickly forms an in situ gel on the wound through crosslinking polymerization when in contact with tissue or blood, demonstrating excellent hemostatic effects both in vitro and in vivo. Furthermore, the gel can be rapidly biodegraded by ester bond hydrolysis with the addition of a cysteamine (CS)-containing solution, allowing for on-demand removal.
BIOMATERIALS SCIENCE
(2023)
Article
Engineering, Multidisciplinary
Xuelian Wu, Vishwa Mohan Tiwari, Kimaya Prasad Suryarao, Richard Tan, Rui Xiao, Haibao Lv, Yilei Zhang, Zhifeng Wang, Wei Min Huang
Summary: We present a cost-effective, highly reliable, and environmentally friendly method for patterned coloring of transparent PET. By varying the stretching speed, different color patterns can be achieved, including transparent, white/translucent, complete white/silver, and various combinations of these colors in PET strips. We investigate the conditions for obtaining high-quality color patterns and the length of the transient region during speed changes.