RSC Advances
·
2014
·Vol. 4
·期 100
·56791-56797
·
IF 3.708
Yulin Cui,Mei Tan,Aidi Zhu,Mingyu Guo
Strain hardening and high resilience are two unique mechanical characteristics of many soft biological hydrogels. However, these properties, especially the strain hardening behaviour, are generally not seen in synthetic polymer hydrogels. Here, hydrogels are prepared by free-radical copolymerization of acrylamide and chain-extended vinyl-modified pseudo-polyrotaxane, which acts as a multifunctional crosslinker. The reactive pseudo-polyrotaxane is based on a β-cyclodextrin monomer and amine-terminated PEG–PPG–PEG (Pluronic F127). The obtained hydrogels can be stretched from 10 to more than 26 times their original length before breaking and withstand a compression strain of 95% and even 98% without fracture. Tensile stretching tests show obvious strain hardening behaviours in high stretching and compression deformation regimes. The strain hardening behaviour in stretching deformation is considered to be the orientation and aggregation of the movable crosslinkers along the axial polymer backbone. Moreover, the formation of a second supramolecular network due to the chain-extension effect may also be responsible for it. Highly resilient behaviours with almost no hysteresis and residual strains are also observed even with a maximum strain of λ = 12 because of the inherent freely movable character of the crosslinkers.
研究领域:
材料科学
·
生物医学工程
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DOI
高影响因子
JOURNAL OF INCLUSION PHENOMENA AND MACROCYCLIC CHEMISTRY
·
2019
·Vol. 96
·期 1
·69-79
·
IF 1.429
Duan Nannan,Ye Lin,Zhang Ai-ying,Feng Zeng-guo
Abstract A series of PPR-based multiblock copolymers were prepared by using a PPR self-assembled from a distal 2-bromoisobutyryl end-capped ferrocenyl containing derivative Br-TEG-Fc-TEG-Br with 4 β-CDs as initiator to initiate the in situ ATRP of NIPAAm in aqueous solution at room temperature. After the ATRP, about 2 β-CDs were resided on the polymeric backbone through a 7 day dialysing purification, but those β-CDs were all slipped off the polymeric chain through a further 7 day dialysing treatment. It suggested that the resulting multiblock copolymers are really the PPR-based instead of the PR-based ones showing an impeded dethreading behavior of β-CDs and the PNIPAAm blocks attached are not bulky enough as polymeric stoppers to end-cap the β-CD-TEG-Fc-TEG PPRs into the PR-based multiblock copolymers. Graphic abstract A series of PPR-based multiblock copolymers were prepared by using a PPR self-assembled from Br-TEG-Fc-TEG-Br with 4 β-CDs as initiator to initiate the aqueous ATRP of NIPAAm. After the polymerization there are about 2 β-CDs still entrapped on the polymeric chain through a 7 day dialyzing purification. Those threaded β-CDs are all slipped off the polymeric backbone through a further 7 day dialyzing treatment.
研究领域:
高分子化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2013
·
IF 2.206
Xiaofeng Wang,Weiyi Xing,Bibo Wang,Panyue Wen,Lei Song,Yuan Hu,Ping Zhang
Polypseudorotaxane (PPR) prepared by the inclusion complex between beta-cyclodextrin (β-CD) and poly(propylene glycol) (PPG) was chosen as a ‘‘green’’ carbon source in intumescent flame retardants (IFRs) and exhibited more effective carbonization and higher degree of graphitic network than that of free β-CD. Its combination with ammonium polyphosphate (APP) and melamine (MA) presented the most excellent char-forming ability whether in nitrogen or in air atmosphere. After blending IFRs into polylactic acid (PLA), the thermal stability was characterized by thermogravimetric analysis (TGA), and their flammability was assessed by limited oxygen index (LOI), vertical combustion, and cone calorimeter. The higher LOI% value and lower total heat release (THR) of PLA2 (which contains 20 wt % APP/MA/PPR mixtures) revealed that it presented more excellent flame retardance. Besides, the results of scanning electron microscopy (SEM) exhibited the existence of more bubbles in the char residue of PLA2.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2013
·
IF 3.172
Qiongbo Zhou,Ding Gao,Jun Liu,Xuzhuo Sun,Lei Zhang,Bin Qi,Haibo Zhang,Chunlan Xia,Xiaohai Zhou
Spontaneous formation of supramolecular vesicles which are triggered by the formation of [4]pseudorotaxane B was demonstrated, whereas both Guest and [2]pseudorotaxane A, the precursors of [4]pseudorotaxane B, only assemble into micelles in DMF/water solution. The remarkable transformation of Guest from micelles to supramolecular vesicles was confirmed through DLS , TEM , and Cryo-TEM experiments. The cumulative release of a model drug, 5-carboxyfluorescein (CF), was used to determine the permeability of the supramolecular vesicles. No leakage of entrapped CF was observed within 48 h by fluorescence measurement, indicating the high stability of supramolecular vesicles. The formation mechanism of supramolecular vesicles self-assembled by [4]pseudorotaxane B was also discussed. In [4]pseudorotaxane B, CB[6] is used to increase the hydrophobic property of site β , which acts as hydrophobic “tail.” Meanwhile, CB[7] plays the role of increasing “head area” of site α , which acts as hydrophilic “head.” The synergistic effect of CB[6] and CB[7] induces the formation of supramolecular vesicles. Moreover, the effect of DMF content was investigated by TEM observations. It was found that the [4]pseudorotaxane B can self-assemble into regular supramolecular vesicles when the DMF content is in the range of 50–70%.
研究领域:
化学
·
材料科学
·
药学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES B-BIOINTERFACES
·
2019
·
IF 3.973
Jun Zhao,Chun-Liu Yu,Wei Fang,Ji-Duan Lin,Guo Chen,Xiao-Qin Wang
Self-assembled polypseudorotaxanes (PPRXs) fabricated with α -cyclodextrin and poly(ethylene glycol) (PEG) or its thiolated derivatives were candidate functional materials for enzyme soft-immobilization, encapsulation and controlled-release. The study of their interaction with Jack bean urease (JBU) indicated that they inconspicuously influenced the activity and stability of JBU during long storage, up to 30 days. The macro-species were inaccessible to JBU’s active site and the steric effect might play a significant role in the stabilization of JBU, when compared with the small-molecular sulfhydryl inhibitor thioglycolic acid. Circular dichroism and fluorescence spectra analyses revealed that thiolated PEG 400 -(SH) 2 and its assembly PPRX 400 (SH) brought in perturbations to certain α -helical or β -sheet domains of JBU, making JBU’s conformation more flexible. The resulting partial unfolding of domains exposed several hydrophobic clusters and varied JBU’s surface hydrophobicity. It also rendered the chromophores more hydrophilic and more bared to the polar environment, leading to the typical bathochromic-shift and quenching in intrinsic and synchronous fluorescence spectra. Moreover, the surface hydrophobicity profile of JBU was depicted by fluorescent probe monitoring and the unique “hydrophobic cave” motif was proposed by analyzing JBU’s structural data from the Protein Data Bank. It should be pointed out that conformational variations mainly occurred at the surface region of JBU, while the buried active bi-nickel center was not markedly influenced by the macro-species. The results demonstrated that the PPRXs might act as a proper carrier for JBU encapsulation or soft-immobilization.
研究领域:
生物化学
·
材料科学
·
酶学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIOMACROMOLECULES
·
2021
·
IF 6.988
Lili Cai,Huatang Zhang,Jianwei Guo,Sa Liu,Yong-Guang Jia
Tuning the fluorescence of aggregation-induced emission (AIE)-based materials in a reversible way is essential and a requisite for their applications. The multiple host–guest interactions of polypseudorotaxanes (PPRs) could alter the aggregation state of hydrophobic AIE-based polymeric materials and consequently switch the fluorescence. Herein, tetraphenylethylene (TPE) as a typical AIE molecule has been incorporated into the main chains of the guest polyurethane via a step condensation between poly(ethylene glycol) (PEG)-based dicarbonate and TPE-diamine along with the cleavable disulfide bonds. γ-Cyclodextrins (γ-CDs) can selectively recognize the TPE units at the polyurethane chains to afford a PPR. Hydrophilic PEG segments and γ-CD molecules in the PPR could promote the disaggregation of TPE units, suppressing the fluorescence emission of TPE. To restore the aggregated state and fluorescence of TPE units, tris(2-carboxyethyl)phosphine (TCEP) and α-amylase are sequentially introduced to cleave the disulfide bonds and cut α-1,4 glycosidic bonds of γ-CD, reactivating the AIE behavior of PPR tandemly and accomplishing the reversible cycle of tuning the fluorescence of TPE. The present study provides a tandem way to switch the AIE behavior of polymeric materials reversibly.
研究领域:
材料科学
·
化学
·
聚合物科学
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DOI
高影响因子
MACROMOLECULAR CHEMISTRY AND PHYSICS
·
2019
·Vol. 220
·期 12
·1900071
·
IF 2.622
Diwei Yan,Sa Liu,Yong-Guang Jia,Lina Mo,Dawei Qi,Jin Wang,Yunhua Chen,Li Ren
Realizing the reversible transformation of the supramolecular hydrogels is essential for their application as smart materials. The reversible sol-gel transition of the polypseudorotaxane (PPR) hydrogels is achieved through adding a CO 2 -switchable guest molecule into the PPR hydrogel of poly(ethylene glycol) (PEG) and α-cyclodextrins (α-CDs). Alternating treatments with CO 2 and heating drive such reversible transition due to the competitive complexation as evidenced by 2D NOESY 1 H NMR and isothermal titration calorimetry as well as X-ray diffraction. The present work describes a straightforward way to obtain switchable PPR hydrogels triggered by a compatible stimulus of CO 2 . These stimuli-responsive PPR hydrogels have potential applications as biomaterials.
研究领域:
材料科学
·
化学
·
生物材料
✓ 已验证
产品关联
DOI
高影响因子
Communications Materials
·
2022
·Vol. 3
·期 1
·1-9
·
IF 0
Wang Shuaipeng,Chen Yong,Sun Yonghui,Qin Yuexiu,Zhang Hui,Yu Xiaoyong,Liu Yu
Slide-ring materials with movable cross-links have received attention due to their excellent mechanical properties. However, due to the poor solubility of polyrotaxane and low synthesis efficiency, their applications are hindered. Here, we use hydroxypropyl-modified α-cyclodextrin (Hy-α-CD) and Acrylamide-PEG 20000 -Acrylamide (ACA-PEG 20000 -ACA) to construct a polypseudorotaxane with good water solubility. Through photo-initiated polymerization of polypseudorotaxane with acrylamide in-situ, the capped polyrotaxane was easily obtained and further cross-linked by 1,4-butanediol diglycidyl ether in sodium hydroxide solution to form a slide-ring supramolecular hydrogel. The hydrogel can be stretched to 25.4 times its original length, which recovers rapidly on unloading, and the addition of Ca 2+ ions during crosslinking enhances ionic conductivity. The Ca 2+ -doped hydrogels are used to prepare wearable strain sensors for monitoring human motion.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
Soft Matter
·
2018
·Vol. 15
·期 1
·73-77
·
IF 3.709
Yi Zhang,Lu Liang,Yong Chen,Xu-Man Chen,Yu Liu
Supramolecular hydrogels, which are usually used to develop excellent smart soft materials, are widely applied in miscellaneous fields due to their inherent reversible properties, unique functions and mechanical properties. Compared with covalently linked hydrogels, supramolecular hydrogels have advantages of easy preparation, stimulus responsiveness and good biocompatibility. Herein, after threading amino-modified β-cyclodextrins onto poly(propyleneglycol)bis(2-amionopropylether) (PPG-NH2) chains, the resultant pseudorotaxanes non-covalently interacted with a clay nanosheet (CNS) matrix to construct supramolecular hydrogels bearing negative charges, and the mechanical properties of these hydrogels were positively correlated with the number of amino groups on the pseudorotaxane. Significantly, these hydrogels presented good adsorption properties for cationic dyes. The adsorption capacity (Qe) of the hydrogels towards rhodamine B (RhB), crystal violet (CV), and methylene blue (MB) could reach 181–228 mg g−1, and most of the dyes were adsorbed within 5 min. Thus, these hydrogels may have potential applications in the field of waste water treatment.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2017
·
IF 3.671
Jun Zhao,Ji-Duan Lin,Jia-Chen Chen,Guo Chen,Xia-Lan Li,Xiao-Qin Wang,Ming-Xia Chen
The self-assembled polypseudorotaxane (PPRX) fabricated with bis-thiolated poly(ethylene glycol) (PEG) and α-cyclodextrin (α-CyD) acted as an activator for α-chymotrypsin (CT) and retained the activity of CT for a long time up to 7 days. The stabilization mechanism was studied, and the interaction between CT and PPRX was analyzed by using circular dichroism, fluorescence spectra and X-ray powder diffraction (XRD). The bis-thiolated PEG and its assembled PPRX with α-CyD exhibited the interaction with the C -terminal region of the CT’s B-chain probably through PEGylation of the surface disulfide bridge of CT. It caused the aromatic chromophores more exposed to the hydrophilic microenvironment, leading to conformational variation of CT that was revealed by spectroscopic analysis. It rendered the peptide chains in a more flexible and active state. As a comparison, the non-thiolated components could not decorate the surface of CT and performed almost no effect on its stability, which demonstrated that the decoration of the surface disulfide bridge was a key factor in retaining the activity of CT. Due to the activation and stabilization effect, bis-thiolated PEG/α-CyD PPRX was an excellent soft-immobilized carrier for CT, and provided an intriguing method for enzyme’s stabilization.
研究领域:
生物化学
·
酶学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ADVANCED MATERIALS
·
2023
·Vol. 35
·期 36
·2301996
·
IF 29.4
Huan Xia,Gang Xu,Xin Cao,Chunyang Miao,Hanning Zhang,Pengyu Chen,Yang Zhou,Wei Zhang,ZhengMing Sun
Flexible zinc-ion batteries (ZIBs) with high capacity and long cycle stability are essential for wearable electronic devices. Hydrogel electrolytes have been developed to provide ion-transfer channels while maintaining the integrity of ZIBs under mechanical strain. However, hydrogel matrices are typically swollen with aqueous salt solutions to increase ionic conductivity, which can hinder intimate contact with electrodes and reduce mechanical properties. To address this, a single-Zn-ion-conducting hydrogel electrolyte (SIHE) is developed by integrating polyacrylamide network and pseudo-polyrotaxane structure. The SIHE exhibits a high Zn 2+ transference number of 0.923 and a high ionic conductivity of 22.4 mS cm −1 at room temperature. Symmetric batteries with SIHE demonstrate stable Zn plating/stripping performance for over 160 h, with a homogenous and smooth Zn deposition layer. Full cells with La-V 2 O 5 cathodes exhibit a high capacity of 439 mA h g −1 at 0.1 A g −1 and excellent capacity retention of 90.2% after 3500 cycles at 5 A g −1 . Moreover, the flexible ZIBs display stable electrochemical performance under harsh conditions, such as bending, cutting, puncturing, and soaking. This work provides a simple design strategy for single-ion-conducting hydrogel electrolytes, which could pave the way for long-life aqueous batteries.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Water Process Engineering
·
2022
·
IF 7.34
Chengdong Guan,Lijuan Yang,Lijun Zhu,Daohong Xia
The fabrication of membranes with the advantages of simple operation and high separation efficiency is considered of great importance to meet the separation challenge of the oil-in-water emulsions produced in various types of industries. Along these lines, in this work, a membrane with a biomimetic gracilaria surface was ingenious designed and manufactured by using poly-pseudorotaxane structured poly ( m -phenylene isophthalamide) (PMIA) for attaining high efficiency of the oil-in-water separation. m-Phenylenediamine (MPD) included by γ-cyclodextrin (γ-CD) was also used to participate in the synthesis of PMIA and introduce more hydroxyl groups into the polymer chains. By the implementation of a non-solvent induced phase-inversion (NIPS) method, the superhydrophilic and the underwater superoleophobic γ-CD@PMIA membrane was successfully fabricated. Under the 0.05 MPa cross-flow filtration test, in addition to the high pure water flux (1366.69 L·m −2 ·h −1 ·bar −1 ) of the γ-CD@PMIA membrane, its separation efficiency for soybean oil-in-water emulsion was higher than 98.20 %. Moreover, during the application of the continuous separation process of up to 4 h, the membrane maintained a stable separation capacity for different oily wastewaters, which proved its good anti-pollution performance. Furthermore, the membrane exhibits good stability in harsh environments, which is of great significance for the future development of membranes with excellent chemical stability. Our work paves the way for the design of a novel biomimetic surface-based membrane with efficient oil-in-water emulsion separation properties.
研究领域:
材料科学
·
环境科学
·
化学工程
✓ 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）