CHEMICAL ENGINEERING JOURNAL
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2020
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IF 10.652
Wu Bin Ying,Haixiong Liu,Peiyuan Gao,Zhengyang Kong,Han Hu,Kai Wang,Ang Shen,Zhijin Jin,Lin Zheng,Hongxia Guo,Ruoyu Zhang,Jin Zhu
Considering the complicated environment in daily use of stretchable devices, the capabilities of anti-stress relaxation, anti-fatigue, anti-fungal and self-healing are very much appreciated, and the above four functionalities largely depend on the elastic matrix. Here, these demands are fulfilled by a poly(thiourethane-urethane) elastomer CBPU-3. In detail, a large amount of cyclohexane rings, with completely reversible boat–chair conformational transition, are introduced into the backbone of poly(thiourethane-urethane), and such non-planar ring imparts molecular elasticity and modulus into the elastomer, resulting in remarkable anti-stress relaxation and anti-fatigue abilities. Even after 20 h fixation at 300% strain and 1000 times cyclic tensile (50% strain), the recovery ratio could still be higher than 98%, and its stable microstructure is proved by SAXS scattering patterns. In addition, the thioether bond ensures the effective mildew proof ability, and the mechanical properties and transmittance change little even after a severe mildew pollution for 30 days. Simultaneously, the relatively lower bond energy of C-S (62.0 Kcal/mol) in thiourethane bonds endowes the poly(thiourethane-urethane) with self-healing capability (highest: 40 μm/min at 80 °C). Finally, the durability and usability of the deformable resistive sensor array based on this elastomer as the matrix are drastically enhanced due to the above integrated functionalities.
研究领域:
材料科学
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生物医学工程
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产品关联
DOI
高影响因子
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
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2025
·Vol. 122
·期 13
·e2416771122
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IF 9.1
Badri Narayanan Narasimhan,Stephanie I. Fraley
In native extracellular matrices (ECM), cells utilize matrix metalloproteinases (MMPs) to degrade and remodel their microenvironment. Accordingly, synthetic matrices have been engineered to permit MMP-mediated cleavage, facilitating cell spreading, migration, and interactions. However, the interplay between matrix degradability and mechanical properties remains underexplored. We hypothesized that MMP activity induces immediate mechanical alterations in the ECM, which are subsequently detected by cells. We observed that both fibrillar collagen and synthetic degradable matrices exhibit enhanced stress relaxation following MMP exposure. Cells responded to these variations in relaxation by modulating their spreading and focal adhesions. Furthermore, we demonstrated that stress relaxation and cell spreading can be precisely controlled through the rational design of matrix degradability. These findings establish a fundamental link between matrix degradability and stress relaxation, with potential implications for a broad spectrum of biological applications.
研究领域:
生物材料学
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细胞生物学
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生物力学
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产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
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2025
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IF 8.2
Hao Nan Qiu,Ji Lin,Li Xin Hou,Rui Xiao,Qiang Zheng,Zi Liang Wu
Various glassy hydrogels are developed by forming dense physical associations within the matrices, which exhibit forced elastic deformation and possess high stiffness, strength, and toughness. Here, the viscoplastic behaviors of the glassy hydrogel of poly(methacrylamide-co-methacrylic acid) are investigated by stress relaxation and creep measurements. We found that the characteristic time of stress relaxation of the glassy gel is much smaller than that of amorphous polymers. The varying hydrogen bond strength leads to a broad distribution of structural activation energies, which in turn affects the range of characteristic time. In the presence of water, the weak hydrogen bond associations are easily disrupted under applied strain, enhancing segmental mobility and reducing relaxation time in the preyield regime, while in the postyield regime, the relaxation time increases slightly since the chain stretching increases the energy barrier. In creep tests, the creep strain rate accelerates at the initial stage due to stress-activated segments and then decelerates as chains are extensively stretched. The stress required for structural activation during creep is much lower than the Young’s modulus of the gel, reflecting the poor structural stability. To further analyze the underlying mechanism of the glassy gel, a micromechanical model is established based on an extension on shear transformation zone theory. By incorporating a state variable for hydrogen bond density, this model can capture the intricate mechanical responses of glassy gels. Our findings reveal that glassy hydrogels are far from the thermodynamic equilibrium state, exhibiting rapid segment activation under external loading. This work provides insights to the dynamics and structural stability of glassy materials and can promote the design and applications of tough hydrogels.
研究领域:
材料科学
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生物力学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
POLYMER INTERNATIONAL
·
2024
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IF 2.9
Shilong Zhang,Youhao Xiong,Yangwei Wang,Yuqi Ma,Jialiang Li,Chaobo Jiang,Ce Wang,Yanling Zhu,Yongsheng Zhao,Guangcheng Zhang
Polyurea (PU) elastomers have attracted considerable attention in the field of protective polymeric coatings. In this work, a dithiol-terminated boronic ester was synthesized and used to incorporate dynamic boron–oxygen (B–O) bonds in the PU main chain based on thiol isocyanate while amino-terminated polydimethylsiloxane (PDMS) was introduced to retain good chain flexibility. The modified PU elastomer was found to have a microphase-separated structure in which the hard blocks served as physical crosslinks. The glass transition temperature ( T g ) slightly increases when dynamic B–O bonds exist while further introduction of PDMS soft segment can lower T g to −55.63 °C. The introduction of dynamic B–O bonds and diminished hydrogen bonding led to a decrease in mechanical strength and elongation at break. Interestingly, the simultaneous incorporation of PDMS and dynamic B–O bonds is favorable for strain rate dependence and suppressing stress relaxation. The potential for bond-exchange interactions between the dynamic B–O bonds and hydroxyl groups on metal surfaces substantially improved the adhesion of the PU elastomer to metal substrates. Therefore, our work can offer valuable insights for the structural design of functional PU coatings tailored for anti-impact applications. © 2024 Society of Chemical Industry.
研究领域:
材料科学
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聚合物化学
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DOI
高影响因子
EUROPEAN POLYMER JOURNAL
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2023
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IF 6
Yang Feng,Hua Qiu,Panhong Deng,Zhuguang Nie,Jinqiu Chen,Kaijie Gong,Xiaodong Fan,Shuhua Qi
Vitrimers, a polymer class that combines the benefits of thermosetting plastics and thermoplastics , have extensive potential applications in our daily lives and industry. Effectively controlling the dynamic properties of vitrimer materials has received considerable attention. This research prepared a series of dynamic epoxy crosslinking network with varying crosslinking densities by introducing reactive monofunctional small-molecule epoxy monomers through a transesterification reaction. Stress relaxation behavior confirmed the impact of small molecular epoxy on the rearrangement of the transesterification topological network. The findings indicated that decreasing the crosslinking density of the resin resulted in shorter stress relaxation time. Adding small molecular epoxy from 0% to 5% increased the tensile strength of the material from 13.2 MPa to 18.1 MPa. The findings demonstrate that it is efficient to adjust the dynamic properties of glass-like polymers by changing the cross-linking density. Furthermore, the mechanical properties of glass-like polymers can be enhanced by appropriately reducing the cross-linking density, which offers a new method for preparing vitrimer materials with desirable properties.
研究领域:
材料科学
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高分子化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2024
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IF 8.3
Yuetian Du,Dong Wang
Although considerable progress has been made in developing different types of vitrimers, ongoing challenges remain in tuning their mechanical and rheological properties, self-healing, and adhesion. Here, we demonstrate a one-pot method to produce a novel double-network epoxy vitrimer using an aliphatic amine cross-linker with a siloxane covalent bond and an aromatic amine cross-linker with a disulfide covalent bond. When a controlled two-stage curing process is employed, the markedly different reactivities of aliphatic amine and aromatic amine with epoxy allow for sequential cross-linked network formation, leading to the development of a double network that incorporates two types of dynamic covalent bonds. As a result, the produced vitrimers exhibit controllable mechanical, thermal, and rheological properties, as well as recyclability. This is evidenced by a tensile strength as high as 72 MPa, while maintaining ∼10% elongation at break, a wide glass-transition temperature range from 91 to 171 °C, and an adjustable two-stage stress relaxation. These characteristics suggest opportunities to develop high-performance cross-linked polymers with specific responses to time and temperatures.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MACROMOLECULES
·
2021
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IF 5.985
Mao Chen,Hongwei Si,Huan Zhang,Lin Zhou,Yeping Wu,Lixian Song,Ming Kang,Xiu-Li Zhao
Vitrimer materials that obscure the line between ″thermoset″ and ″thermoplastic″ have already attracted a great deal of interest since they exhibit dynamic properties of stress relaxation or reprocessability without losing their permanently cross-linked networks. While much research has been aimed at developing new exchangeable dynamic bonds to broaden the scope, there is a dearth of effort in exploring the key factors that influence the dynamic properties of vitrimer materials. These explorations are not only useful in the exact design and synthesis of vitrimer materials but also quite important in their theory establishment and computer simulation. However, only a few ways including catalyst control have been confirmed to be the key factors in controlling the dynamic properties of classical vitrimer materials like the polyester-based epoxy vitrimer. Here, we proposed that the density of exchangeable ester bonds (υ) in networks also has a crucial role in adjusting the dynamic properties of epoxy vitrimers. Four polyester-based epoxy vitrimers were synthesized from the tricarboxylic acid curing agent and different epoxy monomers, resulting in various υ’s. These epoxy vitrimers were named ″E202-vitrimer″, ″E380-vitrimer″, ″E500-vitrimer″, and ″E640-vitrimer″ according to the different molecular weights of the epoxy monomer. It was revealed that the dynamic properties of these vitrimer materials varied with the υ value. From the E640-vitrimer to E202-vitrimer, the stress relaxation behavior sped up with the rise in υ and the characterized relaxation times (τ’s) obviously decreased. Meanwhile, the activation energy (Ea) and the Arrhenius prefactor (τ0), which are two important intrinsic parameters in evaluating the dynamic properties of vitrimers, exhibited heavy dependence on υ, while linear models were applied to describe their relationships. Moreover, the τ at various temperatures could be also predicted from a linear model that relied on the υ in polyester vitrimers. These results indicated that υ has a crucial role in controlling the dynamic properties of polyester-based epoxy vitrimers and the value of υ could be applied to calculate the τ, Ea, and τ0. Besides, the influence of υ on the dynamic properties of polyester-based epoxy vitrimers and the resulted models might be workable in other vitrimer materials, which can be utilized to design desired vitrimer materials for various applications.
研究领域:
材料科学
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高分子化学
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2022
·Vol. 32
·期 39
·2204687
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IF 19.924
Chunhui Wang,Dong Wang,Xin Ma,Haozhe Qin,Mingkai Liu,Yan Yan,Bao Zhang,Xing Ou
High-performance conversion-reaction-based electrodes have received enormous attention due to their high theoretical capacities, yet the poor structural stability and large stress accumulation induced from volume change are identified as major limiting factors for further utilization. Although viable strategies are exerted to acquire durable storage capacity, the controllable technology of inner stress is still required to explore. Herein, the amorphous structured GeS 2 with 2D porous sheet morphology is designed for sodium-ion batteries (SIBs). The differences in reaction mechanism and structure reversibility between amorphous and crystalline states are systematically investigated and unraveled. Notably, the amorphous matrix can ensure evenly distributed intermediate interface and alleviated aggregation of active materials, promoting the complete conversion reaction with decreased hysteresis. Furthermore, it provides more isotropic Na-ion diffusion channels and active sites, effectively boosting the reaction kinetics. Meanwhile, it can fully relieve the volume expansion and restrain the inner stress of GeS 2 , resulting in excellent structural tolerance. As expected, it expresses prominent rate capability and cyclic life (512.8 mA h g −1 at a superhigh rate of 10 A g −1 after 1000 cycles) for SIBs. Therefore, amorphization engineering is a reliable strategy to obtain the robust framework and unimpeded diffusion channels for developing high-performance conversion-reaction-based electrode materials.
研究领域:
材料科学
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电化学
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DOI
高影响因子
Advanced Healthcare Materials
·
2022
·Vol. 12
·期 3
·2202009
·
IF 11.092
Yi Zhang,Liyi Peng,Ke Hu,Ning Gu
Ferroptosis has recently become a research hotspot, and the induction of tumor cell ferroptosis has emerged as a powerful method for tumor therapy. However, the efficiency of tumor cell ferroptosis induction remains unmet for clinical use, which may be attributed to the large discrepancies between in vitro and in vivo models. To address this issue, in this study, a hydrogel platform with stress relaxation is utilized to develop a multicellular spheroid model of the DLD1 colon cancer cell line through cancer cell self-organization. The spheroids are highly similar to real tumor tissue, and ferroptosis resistance at the transcriptional, protein, and cellular levels. Collaboration of the ferroptosis induction reagent erastin and the nanoenzyme MnZnFe 2 O 4 @PEG-COOH to overcome the ferroptosis resistance of the spheroids is also demonstrated. Taken together, this study demonstrates the effectiveness of the model developed using this hydrogel platform for further mechanistic studies, and for the assessment of novel cancer treatment strategies based on ferroptosis.
研究领域:
肿瘤学
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生物材料学
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细胞生物学
✓ 已验证
DOI
PubMed
高影响因子
MACROMOLECULES
·
2020
·
IF 5.918
Qiong Li,Songqi Ma,Sheng Wang,Yanlin Liu,Muhammad Abu Taher,Binbo Wang,Kaifeng Huang,Xiwei Xu,Yingying Han,Jin Zhu
Recycling thermosets have become extremely important due to their ecological and economic benefits. The development of thermosets that undergo reversible polymerization provides a solution to the end-life disposal issue of thermosetting materials. However, the synthesis and recycling of the current chemically recyclable thermosets are harsh, complex, and energy-intensive, and their stability is often low. Here, we designed asymmetric acetal-containing thermosets (PRCs) from general phenolic resin and 1,4-cyclohexanedimethanol divinyl ether through one-step “click” cross-linking without using catalysts and solvents and without releasing small-molecule byproducts. PRCs exhibited conspicuous stress relaxation via a dissociative mechanism, corresponding to the superior malleability and reprocess recyclability. Importantly, PRCs presented excellent creep resistance even at 100 °C. In addition, PRCs could be readily and highly efficiently recovered to original phenolic resin via hydrolysis under specific mild acidic conditions but possessed high chemical stability under neutral conditions and even weak acidic conditions or acidic conditions in the absence of organic solvents with outstanding wettability and swellability toward the samples. Thermosets with different properties could be easily achieved via regulating raw materials. This work provides a promising dynamic covalent motif and a practical method to produce readily dual-recyclable (reprocess recyclable and chemically recyclable) thermosets with superior performance and stability.
研究领域:
材料科学
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绿色化学
✓ 已验证
产品关联
DOI
高影响因子
Materials Science & Engineering C-Materials for Biological Applications
·
2019
·
IF 4.959
Wenqiang Li,Dongwei Wu,Duo Hu,Shanshan Zhu,Cile Pan,Yanpeng Jiao,Lihua Li,Binghong Luo,Changren Zhou,Lu Lu
The mechanical environment of extracellular matrix (ECM) plays an important role in adjusting the behaviors of cells. Natural ECM are highly viscoelastic materials with stress-relaxion behavior. Hydrogel is considered as a promising and attractive material for cell carrier, but they are typically elastic serving as synthetic ECM. Double-network (DN) hydrogel has an interpenetrating network of special structure combining the advantages of both rigid and ductile components, due to which the mechanical properties of the system can be very different from that of the single-network ones, and some special biological properties can be obtained. In this study, GG/PEGDA DN hydrogel was prepared by combining gellan gum (GG) with polyethylene glycol diacrylate (PEGDA), and then the influence of the two individual networks on the viscoelasticity of the system were investigated. Furthermore, the effects of viscoelasticity of GG/PEGDA DN hydrogel on the biological behavior of bone mesenchymal stem cells (BMSCs) were explored in vitro and in vivo . The results indicate that the spreading of BMSCs was closely related to the relaxation behavior of the hydrogels. GG/PEGDA DN hydrogel shows excellent mechanical and relaxation properties which provide a favorable physical environment for cell proliferation and spreading, and induce chondrogenic differentiation. Our study demonstrates that this DN hydrogel has bright prospects in the fields of cell carrier and cartilage tissue engineering.
研究领域:
组织工程
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生物材料
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细胞生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2024
·
IF 8.1
Jia Yang,Haoyue Li,Xin Yue,Qiuguang Zhang,Mengchun Fu,Jiujie Xu,Ke Li,Ce Wang,Panpan Lin,Peng He,Tiesong Lin,Yanli Zhuang,Han Mei,Yue Liu
Stress relaxation plays a key role in ceramic/metal joints, and reliable information is crucial for developing multilayer composite fillers and reaching promising joint strengths. There are currently limited relevant experimental studies due to the difficulty in detection. Taking the Al 2 O 3 /stainless steel joint as an example, the study gives a new method to unveil the role of elastic-plasticity of sandwich composites in stress relaxation. By using the thermo-hydrogen treatment technology, the joint strength was almost only affected by the thermal mismatch at a fixed brazing parameter, which can be an indirect indicator of stress relaxation. In the meantime, it is a promising method for stress relief. It was found that the joint strength, which corresponds to the residual stress relaxation, was promoted by the presence of hydrogen, which corresponds to the elastoplastic properties of the fillers. This dependency was amplified in the harder/softer/harder structure. Finite element analysis verified the experiment results by calculating the stress concentration, strain energy density, equivalent moment, and shear forces at stress-concentrated regions because the more ductile interlayer had higher strain but lower stress, and easier plastic deformation during the brazing process. The occurrence of dislocation movement, grain boundary slip, stacking fault, and dynamic crystallization played a significant role in the plastic deformation.
研究领域:
材料科学
·
力学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）