ACS Applied Materials & Interfaces
·
2022
·
IF 10.383
Han-Xiao Wang,Xin-Yu Zhao,Jin-Qiang Jiang,Zhao-Tie Liu,Zhong-Wen Liu,Guo Li
Thermal-responsive hydrogel actuators have aroused a wide scope of research interest and have been extensively studied. However, their actuating behaviors are usually monotonous due to their unchangeable shapes and structures. Here, we report thermal-responsive poly(isopropylacrylamide-co-2-(dimethylamino)ethyl methacrylate)/alginate hydrogels with programmable external shapes and internal actuating trajectories. The volume phase transition temperatures of the resulting hydrogels can be tuned in a wide temperature range from 32 to above 50 °C by adjusting the monomer composition. While the formation and photo-dissociation of Fe3+–carboxylate tri-coordinates within the entire hydrogel network enable photo-responsive shape memory property, the insufficient dissociation of the tri-coordinates along the irradiation path gives rise to gradient crosslinking for realizing thermal-responsive actuation. Controlling the evolution of the gradient structure facilitates the regulation of the actuating amplitude. Furthermore, we show that the combination of these two types of shape-changing functionalities leads to more flexible and intricate shape-changing behaviors. One interesting application, a programmable hook with changeable actuating behaviors for lifting different objects with specific shapes, is also demonstrated. The proposed strategy can be extended to other types of actuating hydrogels with more advanced actuating behaviors.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
·
2022
·
IF 6.76
Dujuan Hu,Yanbo Li,Zhiguo Yan,Shaoping Li,Man Xu,Cunwen Wang
Nanofiltration membranes with excellent anti-fouling properties were fabricated through a green surface crosslink method. Poly (styrene-maleic anhydride) (SMA) blended polyethersulfone (PES) membrane was used as a support. The SMA in the PES support served as a macromolecular crosslinker. After coating of polyvinyl alcohol (PVA) on the surface of the SMA-PES support, a PVA selective layer with gradient cross-linked structure was formed, through the esterification between the anhydride groups in SMA and the hydroxyl groups in PVA. This process adopts a full-water fabrication strategy without secondary pollution. The gradiently cross-linked PVA/SMA-PES membrane, with molecular weight cut-off (MWCO) about 600 Da and permeance around 10-12 L/(m 2 ·h·bar), exhibited good dye/salts separation performance. In the filtration of a mixed solution of Congo Red (CR) and calcium chloride (CaCl 2 ), the membrane rejected 98% CR and only had 10% rejection of CaCl 2 . In addition, this membrane processed an excellent anti-fouling property. In the BSA fouling test, the pure water flux recovery ratio (FRR) was 99%. It is expected that the PVA/SMA-PES membrane can be used in organic desalination.
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
DESALINATION
·
2021
·
IF 9.501
Binbin Yang,Kaifeng Gu,Shuhao Wang,Zhuan Yi,Yong Zhou,Congjie Gao
Chitosan (CTS) and 1,3,5-triglycidyl isocyanurate (TGIC) were gradiently cross-linked on the polyethersulfone ultrafiltration membrane (PES) to prepare a new type of positively charged composite nanofiltration membrane. The influence of preparing conditions on the membrane performance , such as permeability, mechanical strength, membrane morphology, and nanostructures was systematically discussed. The rejection performance to MgCl 2 , Na 2 SO 4 , MgSO 4 , and NaCl revealed that the prepared membrane was positively charged. The membrane prepared under the optimal conditions showed a molecular weight cut-off of 1500 Da. Finally, rejections to heavy metal ions were determined, and excellent removal rate was found. Among the nanofiltration membranes prepared from chitosan, CTS/TGIC-NF membranes prepared in the current work exhibited superior permeability and mechanical strength to the membranes shown in literature, indicating that our membranes can be used to reduce water hardness and produce portable water.
研究领域:
材料科学
·
环境工程
·
生物材料
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2025
·
IF 9
Ziheng Li,Shenghan Ji,Fengting Yao,Yan Dai,Xuehua Ruan,Xiaobin Jiang,Wenji Zheng,Gaohong He
Covalent organic frameworks (COFs) are regarded as disruptive membrane materials owing to their versatile functionalities, high stability and ordered nanochannels. However, a major obstacle to the application of COF-based membranes in gas separation is the inherent size difference between their pore sizes and target gas molecules. Herein, we employed a confined cross-linking strategy to graft CO 2 -philic poly-ethyleneimine (PEI) onto carboxylic acid-type iCOF membranes, constructing a gradient wedge-shaped pore wall structure to enhance H 2 separation. High-density carboxyl group-containing iCOF nanosheets were prepared via an improved single-phase solution method and assembled into membranes. 1-ethyl-3-(3-dimethylami-nopropyl) carbodiimide/N-Hydroxysuccinimide (EDC/NHS) coupling chemistry was used to functionalize iCOF membranes with PEI. The introduction of a large number of amino groups via PEI enhances CO 2 adsorption by 81.4%. Meanwhile, the grafting of PEI reduces defects or pinholes on the membrane surface and improves the mechanical properties and stability. As a result, the PEI-functionalized iCOF@PEI-4 membrane exhibits a H 2 permeance of 1103 GPU and an H 2 /CO 2 selectivity of 21.3, positioning its performance among advanced membranes and surpassing the 2008 Robeson upper bound. Customized structural design of iCOF membranes through tailored functionalization may provide insights for designing molecularly selective COF membranes.
研究领域:
材料科学
·
膜分离技术
·
纳米材料
·
化学工程
·
功能高分子
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2021
·
IF 9.229
Qiwen Yan,Lina Mao,Bang Feng,Lidong Zhang,Yiqian Wu,Wei Huang
A series of novel humidity-responsive and photosensitive polymer films (PCA–PAA–PEG) are prepared. These films can be patterning cross-linked by the photodimerization of coumarin pendant groups. The humidity-induced deformation can be well controlled by the pattern because of the different modulus and hydrophilicity between cross-linked and un-cross-linked segments. In addition, the pattern can be erased and the deformation direction can be changed programmatically by the de-cross-linking–re-cross-linking approach due to the reversible photodimerization of coumarin groups. The cross-linking degree also affects the humidity responsiveness of the film. The deformation of the gradient patterning cross-linked film can be more accurately controlled. Moreover, the length and width ratio (L/Ws/Wh) of the un-cross-linked segment to the cross-linked segment affects the deformation of the films as well. When L/Ws/Wh is 5/2/1 or 5/3/1, the deformation is controllable, and when L/Ws/Wh is 5/1/1 or 5/4/1, the deformation is random at the initial stage, but the whole film will bend along the short axis in the end.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2023
·
IF 9.5
Ling Hu,Jinqiang Jiang,Zhao-Tie Liu,Zhong-Wen Liu,Guo Li
Polymeric materials that can actuate under the stimulation of environmental signals have attracted considerable attention in fields including artificial muscles, soft robotics, implantable devices, etc. To date, the improvement of shape-changing flexibility is mainly limited by their unchangeable shapes and structural and compositional distributions. In this work, we report a one-step treatment process to convert 2D poly(ethylene oxide)/sodium alginate/tannic acid thin films into 3D-shaped moisture- and NIR light-responsive actuators. Spatial surface wetting of the film leads to the release of residual stress generated in film formation in a gradient manner, which drives the wetted regions to bidirectionally bend. By controlling the position and bending amplitude of the wetted regions, designated 3D shapes can be obtained. Moreover, Fe3+ ions in the aqueous solution used for surface wetting can coordinate with carboxylate groups in sodium alginate chains to form a gradient cross-linking network. This gradient network can not only stabilize the resulting 3D shape but also render the film with moisture-responsive morphing behaviors. Fe3+ ions can also self-assemble with tannic acid molecules to form photothermal aggregates, making the film responsive to NIR light. We further show that films with versatile 3D shapes and different modes of deformation can be fabricated by a one-step treatment process. This strategy is convenient and extendable to develop 3D-shaped polymer actuators with flexible shape-changing behaviors.
研究领域:
材料科学
·
软体机器人技术
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生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2018
·
IF 6.578
Miao Guo,Shuhao Wang,Kaifeng Gu,Xiaoxiao Song,Yong Zhou,Congjie Gao
Performance enhancement of the TFC membrane depends on the fine design of the functional layer. In this study, a gradient cross-linking strategy has been successfully applied to fabricate an ultra-thin gradient cross-linked PVA (GC-PVA) functional layer with the aid of surfactant on a polysulfone (PSF) support membrane. Such a strategy was accomplished by impregnating the crosslinker (Trimesic acid) on the porous support membrane prior to PVA coating. As confirmed by XPS and EDX studies, the GC-PVA membrane features a gradient cross-linked structure, where the bottom surface is densely cross-linked while the top is only slightly cross-linked. Overall, the lowest thickness achieved by the gradient-crosslinked ultrathin functional layer was 75.4 nm. This strategy significantly improved water flux compared with the conventional fully cross-linked PVA membranes while similar salt rejections can be maintained. In addition, the impact of key fabrication parameters, such as the concentration of PVA, surfactant, crosslinker, and the post-treatment temperature has been systematically studied. The optimized membrane had a significantly high water flux of 72.9 L m −2 h −1 at 0.2 MPa and showed rejection rates of 38.2% and 90.7% towards NaCl, Na 2 SO 4 aqueous solution (500 mg/L), respectively.
研究领域:
材料科学
·
膜分离技术
·
高分子化学
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纳米功能材料
·
环境工程
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Xiaoyan Leng,Wei Qin,Ning Guo,Xinliang Liu,Ming Wang,Yingfei Hou
Dimethyl carbonate (DMC) was widely used as an environmentally friendly organic compound. However, the production process of DMC generated a methanol (MeOH)/DMC azeotrope, which increased the separation cost. Pervaporation technology was considered a promising method for the separation of MeOH/DMC. Based on the polarity differences between MeOH and DMC, polyethyleneimine (PEI) with abundant polar groups ( NH 2 ) was selected as the membrane material for the separation of MeOH/DMC. We enhanced the organic solvent swelling resistance of PEI through in situ growth of SiO 2 and surface gradient crosslinking modifications. The results demonstrated that both the in-situ growth of SiO 2 and the surface gradient crosslinking modification significantly improved the membrane’s resistance to organic solvent swelling. However, the surface gradient crosslinking was the primary factor contributing to the enhancement. The membrane performance is optimized by adjusting the PEI concentration, TEOS concentration, TEOS reaction time, TMC concentration, and TMC crosslinking time. The prepared membrane achieved a flux of 0.9 kg·m −2 ·h −1 , with a separation factor of 54, and maintained stable operation for 50 h.
研究领域:
化学工程
·
材料科学
✓ 已验证
DOI
高影响因子
DESALINATION
·
2025
·
IF 9.8
Rui Hou,Pei Wang,Chao Cheng,Jianlong Dai,Wentao Yan,Yong Zhou,Congjie Gao
The global generation of industrial wastewater has caused substantial heavy metal contamination, posing a severe threat to human health and environment. Nanofiltration (NF) membranes have gained widespread application in water treatment. However, traditional NF membranes typically feature the mixed separation zone and permeation zone, which hinder the simultaneous improvement of separation and permeation performance. Herein, we developed a gradient cross-linking NF membrane with a customized quaternized surface for the efficient removal of heavy metal ions. The loose upper layer of the gradient cross-linking structure was responsible for the high water flux, while the dense lower layer was accounted for rejecting heavy metal ions. The quaternized surface (glycidyl trimethyl ammonium chloride (GTMAC) grafted surface) endowed membrane with an enhanced positive charge characteristic, thereby improving its removal performance by repelling positively charged metal ions. Meanwhile, GTMAC rendered the membrane surface with enhanced water affinity, thus further enhancing the water permeance. Concretely, the resultant GTMAC-PEI/TMA membrane achieved satisfactory rejection rates for Mn 2+ (96.7 %), Cu 2+ (95.2 %), Ni 2+ (96.2 %) and Zn 2+ (93.3 %), with high water flux of 19.1–20.6 L m −2 h −1 bar −1 . This strategy provides an insight for the development of NF membranes with simultaneously improved permeability and rejection performance in heavy metal removal application.
研究领域:
环境科学
·
材料工程
·
化学工程
·
水净化技术
✓ 已验证
产品关联
DOI
高影响因子
Advanced Composites and Hybrid Materials
·
2025
·Vol. 8
·期 6
·423
·
IF 21.8
Cheng Yu,Li Sen,Liang Siqi,Yi Zhengkun,Chang Yu,Zhang Yi,Sun Bin,Peng Tao,Wu Shaohui,Li Jing,Yang Hui,Sun Hongyan
Rapid wound closure is crucial to prevent microbial invasion during skin trauma. Delayed diagnosis and treatment of wound infection may lead to complications such as impaired healing and sepsis. Conventional clinical dressings (e.g., cotton and gauze) mainly provide physical isolation but fail to establish an antibacterial microenvironment. These dressings often adhere to wound tissues, resulting in secondary injury during removal, and lack the capability for real-time monitoring of wound conditions. This study innovatively integrates multimodal pressure sensing with wound repair functions, enabling the synergistic development of smart sensing wound dressings (SSWD) that offer real-time visual monitoring. The dressing employs gradient cross-linking to fabricate a dynamic self-adaptive Janus-structured organic hydrogel. The upper non-adhesive ion-sensing layer incorporates micro-nano surface structures, enabling high-resolution real-time responses to mechanical signals from wound swelling and tissue regeneration. This capability, when coupled with an image acquisition system, enables visual monitoring of the healing process. The lower adhesive layer ensures robust interfacial integration with the wounds’ bed via hydrogen bonding while allowing controlled sustained release of drugs that promote healing. This system propels the development of intelligent dressings towards diagnosis-treatment integration and offers an innovative solution for precision wound management.
研究领域:
生物医学工程
·
伤口护理
·
智能材料
·
水凝胶技术
·
可穿戴传感器
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2023
·
IF 9.5
Haojie Zeng,Feiyun Sun,Jianjun Zhang,Ying Wang,Songwen Yang,Dingyu Xing
Polyvinyl alcohol (PVA) has been employed and crosslinked as the selective layer of NF membranes with enhanced hydrophilicity. However, the influences of different crosslinking methods and agents on the reaction mechanism and membrane performance still need to be comprehensively studied. In this study, NF membranes were prepared by coating crosslinking (CC-membrane) and gradient crosslinking (GC-membrane) methods. Compared with CC-membrane, the GC-membrane possessed a 65% higher flux with Na 2 SO 4 rejection around 90%, under the optimal preparation conditions with PVA content of 0.10%, curing at 80 °C for 10 min. Crosslinking agents including 1,3,5-benzenetricarboxylic acid (TMA), 4,4′-(hexafluoroisopropylidene) diphthalic anhydride (6FDA) and pyromellitic dianhydride (PMDA) with different spatial structure were used to optimize the GC-membrane. As confirmed by SEM, XPS, FTIR and contact angle tests, the 6FDA-GC membrane showed a thinner, smoother and more hydrophilic selective layer, and kept an excellent balance between the water flux (88.6 L/m 2 h) and Na 2 SO 4 rejection (88.7%). This is because the 6FDA with a large molecule and flexible spatial structure could form a more integrated crosslinking structure compared to PMDA. Meanwhile, the 6FDA-GC membrane showed rejections of over 80% towards the endocrine-disrupting compound 17α-Ethinylestradiol and exhibited stable antifouling ability and durability. Overall, this work studied systematically the influences of various crosslinking agents on the GC-membrane, and verified the potential of hydrophilic PVA membranes for nanofiltration.
研究领域:
材料科学
·
化学工程
·
环境科学
·
膜技术
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）