POLYMER TESTING
·
2023
·
IF 5.1
Hechen Liu,Zhanglin Sun,Liwei Wei,Yunpeng Liu,Songsong Zhou,Qi Ge,Chang Liu,Xinyang Li
Traditional thermosetting epoxy resins are widely applied in many fields due to their excellent performance. However, stable internal crosslinked networks hinder the repair of epoxy resins damaged during the operation and the recycling of decommissioned epoxy resins. Since vitrimers are epoxy resins that exhibit dynamic covalent bonding, reversible repair properties, and recyclability, they offer a potential solution to this problem. Therefore, by introducing an ester-exchange catalyst, we further introduced disulfide (S–S) bonds to the crosslinked network to construct a vitrimer resin exhibiting double-dynamic bonds, systematically investigated the basic thermodynamic and electrical properties of resins containing different S–S bond contents, and studied the self-healing properties of the possible multispecies and multiscale physical and electrical damages during device operation. Moreover, we investigated the self-healing properties of resins containing different S–S bonding contents. Results showed that the resin exhibited excellent electrical insulation, and the dynamic properties of the resin increased with the increasing number of S–S bonds in the crosslinked network, which considerably increased the repair efficiency and damage repair scale. In addition, the excellent dynamic properties rendered the resin degradable, enabling the non-destructive recycling of valuable materials from the resin matrix and specific processable remodelling and endowed the resin with thermally elastic shape memory properties. This work helps expand the class of vitrimer resins and promotes the application of vitrimers for manufacturing environmentally friendly electrical equipment.
研究领域:
材料科学
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高分子化学
·
绿色化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2021
·
IF 9.229
Qijun Chen,Yuchen Shi,Kai Sheng,Jianming Zheng,Chunye Xu
It is desired to develop self-healing gel electrolytes for flexible electrochromic devices (ECDs) due to the demand of healing damages caused during operations. We here report a hydrogel electrolyte with remarkable self-healing capability, excellent stretchability, and ionic conductivity. The hydrogel electrolyte was synthesized via one-step copolymerization of glycerol monomethacrylate (GMA) and acrylamide (AAm) in the presence of borate. Within the hydrogel electrolyte, dynamic cross-linking is expected to be formed due to the borate-didiol complexation and hydrogen-bonding interactions. As a result, the hydrogel electrolyte demonstrates an excellent self-healing efficiency of up to 97%, a fracture strain of 1155%, a fracture toughness of 136.6 kJ m–3, and a fracture stress of 13.0 kPa. Additionally, a flexible ECD based on the hydrogel electrolyte and an electrochromic layer of poly(3,4-(2,2-dimethyl-propylenedioxy)thiophene) (PProDOT-Me2) was assembled and evaluated. The device is found to be stable in both mechanical and optical properties over 1000 operation cycles. This study may provide a promising way for self-healing electrolyte gels to be utilized in a variety of flexible electrochemical devices, including ECDs, supercapacitors, and batteries.
研究领域:
材料科学
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电化学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 36
·30570-30576
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IF 3.289
Qiang Su,Yajun Wang,Shuang Guan,Huixuan Zhang,Guang Hui Gao,Xinyuan Zhu
Highly stretchable and notch-insensitive hydrogels were rapidly prepared using redox initiators. The hydrogels had a large number of non-covalent crosslinking points, which come from hydrophobic side chains and metal ion coordination without any chemical crosslinking agents. The non-covalent crosslinking points in the hydrogels were stochastic and dynamic, compared to the covalent crosslinking points. When the notched sample was stretched, the hydrophobic segments would contribute to elongation of the hydrogels via molecular stretching. When the hydrogels had a notch, new crosslinking points could be formed via metal ion coordination, even if some previous metal ion–ligand bonds were destroyed. As a result, the sample notch was blunted, widened and merged into the edge gradually under tensile stress. The hydrogels could be elongated up to 12 times their original length and show notch-insensitive properties. Moreover, the metal ion coordination interaction between the amide groups and Fe3+ was proved using Fourier transform infrared spectroscopy (FTIR). The rheological properties and internal morphology of the hydrogels were also measured with different dosages of hydrophobic segments and metal ions. Thus, it was envisioned that the non-covalent bonds would make it possible to create hydrogels with more unexpected properties.
研究领域:
材料科学
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生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2020
·
IF 3.99
Mingwei Zhao,Yang Li,Zhongliang Xu,Kai Wang,Mingwei Gao,Wenjiao Lv,Caili Dai
In petroleum exploitation, fracturing is a very important technique for the reservoir with low porosity and permeability. The fracturing fluid is the key to fracturing operation. Due to the limitation of lithology complexity, it is difficult for conventional acid-based fracturing fluids to meet technical requirements during the production of carbonate oil and gas resources. In this work, a novel acid gel fracturing fluid was designed. The system has high viscosity which is convenient to carry proppant. Meanwhile, the fluid has good basic properties to meet on-site operation requirements. Since the properties of fracturing fluid depend not only on the molecular structure of thickener, but also on the crosslinked structure formed by polymer and crosslinker. The dynamic cross-linking mechanism of this acid gel fracturing fluid system was focused on. The differences in fluid properties between polymer based fluid and fracturing fluid were investigated by conducting viscoelastic tests. A rheological dynamic model based on the change of viscosity with reaction time was established. The effect of shear rate on cross-linking viscosity and reaction rate was studied. Moreover, the microstructure changes of the system before and after the gelation reaction were revealed through the scanning electron microscopy (SEM) experiment. Based on these experimental results, the cross-linking mechanism of this novel acid gel fracturing fluid can be concluded, which benefits the application in oilfield.
研究领域:
石油工程
·
材料科学
✓ 已验证
DOI
高影响因子
Gels
·
2022
·Vol. 9
·期 1
·24
·
IF 4.432
Minhua Liu,Yate Huang,Chunwen Tao,Weijia Yang,Junrong Chen,Li Zhu,Tonghe Pan,Ravin Narain,Kaihui Nan,Yangjun Chen
Oxidative stress is considered as a major factor causing retinal pigment epithelium (RPE) dysfunction and finally leading to retinal diseases such as age-related macular degeneration (AMD). Developing hydrogels for RPE cell delivery, especially those with antioxidant feature, is emerging as a promising approach for AMD treatment. Herein, a readily prepared antioxidant alginate-based hydrogel was developed to serve as a cytoprotective agent for RPE cells against oxidative damage. Alg-BOB was synthesized via conjugation of benzoxaborole (BOB) to the polysaccharide backbone. Hydrogels were formed through self-crosslinking of Alg-BOB based on benzoxaborole-diol complexation. The resulting hydrogel showed porous micro-structure, pH dependent mechanical strength and excellent self-healing, remolding, and injectable properties. Moreover, the hydrogel exhibited excellent cytocompatibility and could efficiently scavenge reactive oxygen species (ROS) to achieve an enhanced viability of ARPE-19 cells under oxidative condition. Altogether, our study reveals that the antioxidant Alg-BOB hydrogel represents an eligible candidate for RPE delivery and AMD treatment.Keywords:alginate;self-healing hydrogel;dynamic crosslinking;oxidative stress;retinal pigment epithelium
研究领域:
材料科学
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生物医学工程
·
眼科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2023
·Vol. 33
·期 12
·2213294
·
IF 19
Weijun Yang,Yanlin Zhu,Tianxi Liu,Debora Puglia,Jose M. Kenny,Pengwu Xu,Rui Zhang,Piming Ma
High-performance elastomers are expected to possess excellent healing and recycling ability, damage resistance in conjunction with high strength and toughness. Herein, a dual dynamic crosslinking strategy is implemented by multiple hydrogen and disulfide bonds to obtain a novel amorphous and transparent polyurethane/nanocellulose elastomer with excellent self-healing, self-reinforcing and toughening performance. First, hydrogen bonds are introduced in TEMPO-oxidized cellulose nanofibers (TCNF) by modification with 2-ureido-4[1H]-pyrimidone (UTCNF), while disulfide bonds (SS) are introduced in the polyurethane (PU) main chain, leading to the formation of dual dynamic cross-linking networks. The PU-SS-UTCNF elastomer can fully self-heal within 4.0 h at 50 °C. Surprisingly, for the first time, the PU-SS-UTCNF elastomer also self-strengthens and self-toughens after multiple hot-pressing, with tensile strength and toughness that increase by up to 401% and 257% compared to original elastomer samples, up to 50.0 MPa and 132.5 MJ m -3 . The self-strength and self-toughening effects are attributed to 1) reconstruction of dual dynamic networks that increase the cross-linking degree during the multiple hot-pressing processes; 2) multiple hydrogen bonds in the system are beneficial to the orientation of highly crystallized UTCNF, as a replacement of stress-induced process in deformation under external tensile force.
研究领域:
材料科学
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高分子化学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
MACROMOLECULES
·
2024
·
IF 5.1
Yikai Sun,Chengfeng Zhang,Shu Wang,Zhenghai Tang,Xinrang Li,Xianming Zhang,Baochun Guo
High gas barrier rubber composites are crucial for the applications requiring the combination of high resilience and gas impermeability. Layered fillers are commonly used to enhance the gas barrier performance by reducing free volume and creating tortuous gas diffusion paths. However, it remains challenging to strengthen interfacial interactions and manipulate filler distribution, which significantly affect free volume and gas diffusion paths. Herein, we present a facile strategy to build a segregated structure in modified rubber composites with dynamic interfacial cross-linking toward mechanically robust, high gas barrier elastomer composites. Concretely, boehmite (BM) nanoplatelets modified with biobased phytic acid (PA) are utilized to cross-link epoxidized natural rubber (ENR), forming dynamic β-hydroxy phosphate ester cross-links for strong interfacial interaction. This system allows a segregated structure to be readily established by hot pressing the compounds containing ENR gum, PA-modified BM, precross-linked ENR granules and zinc acetate. The volume exclusion effect of ENR granules drives the selective dispersion of BM, generating a two-phase segregated structure with the bridged interfaces across phases formed via bond exchange of dynamic cross-links. This results in excellent gas barrier performance along with distinctly improved mechanical properties. Notably, the N2 permeability of the segregated composites is reduced by 90% to 4.23 × 10–19 m3·m/(m2·s·Pa) compared to neat ENR. Additionally, improved fire safety is achieved benefiting from the combined effects of PA, BM, and the segregated structure. This work offers a promising and scalable approach for fabricating high-performance elastomer composites that combine outstanding gas barrier properties, mechanical durability and flame retardance, making them suitable for a wide range of demanding applications.
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
FirePhysChem
·
2025
·
IF 3.6
Chunyan Li,Shenjuan Shao,Jiao Chen,Chongwei An,Baoyun Ye
The development of miniaturized, flexible MEMS pyrotechnic devices necessitates advanced fabrication techniques. Herein, a strategy is reported that leverages the integration of ink-jet printing and dynamic cross-linking. The strategy successfully fabricates CL-20/PVA (polyvinyl alcohol)@PANI (polyaniline) energetic films with robust interfacial adhesion across heterogeneous structures. The PVA@PANI dynamic bonding system, designed through a molecular engineering strategy, provides dual interfacial enhancement characteristics. The 3D network structure formed by dynamic covalent cross-linking of borate ester bonds significantly enhances the flexibility of the system, as demonstrated by a 62.26% improvement in elastic recovery and a 55.26% increase in the plasticity index. Additionally, multiple hydrogen bonding interactions between hydroxyl groups and the substrate substantially improve interfacial adhesion, achieving a 4B rating on both glass and aluminum substrates. SEM characterization reveals a uniform and dense microstructure with homogeneously distributed crystals throughout the composite film. Performance testing confirms that CL-20 in the composite retains its ε-crystal form and exhibits a high detonation velocity of 7884 m·s⁻¹. Furthermore, the synergistic incorporation of PANI reduces the electrostatic sensitivity by 10.86% compared to the CL-20/PVA baseline. The interfacial dynamic enhancement technology developed in this work represents a key advancement in the integrated structure–function design of microscale energetic devices, underscoring its strong potential for MEMS applications such as flexible micro-initiators and miniature solid propellants.
✓ 已验证
产品关联
DOI
高影响因子
Materials Advances
·
2022
·Vol. 3
·期 16
·6609-6618
·
IF 0
Mengyun Zhang,Shanjun Ding,Riming Cong,Yunjun Luo
Waterborne polyurethanes (WPUs), commonly used as coatings and adhesives, produce microcracks when suffering from severe environmental stimuli or continuous mechanical loads. So far, there have only been limited self-healing functional groups, such as disulfide bonds, or Diels–Alder reactions, utilized in WPUs. Herein, we have prepared a novel self-healing waterborne polyurethane (SHWPU) by introducing silver–thiol coordination interactions, which exhibit excellent self-healing performance. WPU–Ag@S-0.50 with microcracks could recover to its original state at room temperature within 30 min. The self-healing efficiency in terms of its tensile strength is 98.69%, demonstrating that introducing silver–thiol coordination interactions is an effective strategy to realize self-healing.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
ACS Applied Polymer Materials
·
2025
·
IF 4.7
Wei Zheng,Wenxin Deng,Shaofeng Xiong,Zhefeng Jin,Jiangpeng Hu,Yujia Zhao,Xuhuang Chen,Siwen Bi,Peng Yu
The preparation of foams with self-healing properties and stable cell structures continues to present significant challenges. In this study, a polydimethylsiloxane elastomer featuring a dual network structure was developed. A dynamic cross-linking network, formed by hydrogen and disulfide bonds, imparted self-healing capabilities to the elastomer. The inclusion of a cross-linking agent created an inherent cross-linking network that improved the mechanical properties and melt strength of the elastomer. The synthesized polydimethylsiloxane elastomer demonstrated an exceptional self-healing performance, achieving a self-healing efficiency of 92.89%, along with impressive mechanical properties, including a tensile strength of 6.32 MPa and an elongation at break of 1277.80%. Additionally, a polydimethylsiloxane elastomer foam with self-healing properties was fabricated using a supercritical carbon dioxide (sc-CO2) foaming method. With an increase in inherent cross-linking, the cell size decreased from 11.88 to 8.60 μm, while the cell density increased from 2.04 × 109 to 2.71 × 109 cells/cm3, resulting in the uniform cell distribution within the foam. Microcracks in the foam were effectively healed within 10 min at 80 °C, and the cell morphology remained stable after 96 h of exposure to environmental conditions. This dual-network self-healing foam exhibited an excellent self-healing performance along with a stable cell structure.
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
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
WeiMing Zhou,Sijia Sun,Yuting Zhang,Shuaiqi Wang,Shuai Zhang,Shengjie Ling,Changtong Mei,Mingzhu Pan
With the rapid development of the 5G era and smart homes, self-healing and self-powered smart fire sensors are considered a promising solution for emerging applications, but fabricating such sensors remains a great challenge. In this study, a highly efficient dynamic crosslinking strategy was developed to construct a self-healing organic–inorganic hybrid material (OIH). More precisely, self-healing OIHs were fabricated through a simple Schiff reaction between chitosan and a Ti 3 O 5 metal–insulator transitional material. The incorporation of multi-crosslinked networks (C N, hydrogen bonds, electrostatic interactions) provided stable charge migration paths for the free movement of protons and hot electrons. Accordingly, the OIH exhibited a substantially enhanced fire-response sensitivity (1.09 s). Moreover, this OIH was capable of self-healing while recovering its fire-warning properties. The OIH intelligent system exhibited good universality on various substrates, such as wood, paper, fiberglass fabrics, and polyurethane (PU) foam. By introducing a self-healing OIH into a fire alarm platform, a highly sensitive warning signal can be sent via Wi-fi or Internet applications. Moreover, a self-powered fire-warning system with triboelectric nanogenerator (TENG) is also demonstrated using OIH. The concept of combining a self-healing and self-powered fire-sensing system may provide potential solutions for applying OIH in emerging applications.
研究领域:
材料科学
·
智能传感
·
能源技术
·
消防安全
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POLYMER SCIENCE
·
2021
·Vol. 59
·期 16
·1807-1820
·
IF 0
Tianyu Gong,Longhai Guo,Jun Ye,Lifan He,Teng Qiu,Xiaoyu Li
The implementation of covalent adaptable networks (CANs) in general resin system is becoming attractive. In this work, we propose a simple post-curing strategy based on the core-shell structured acrylate latex for the achievement on both the improved general performance and the CANs characteristics in latex films. The building to the CANs was relied on the introduction of 4,4′-diaminophenyl disulfide as the curing agent, which cured the acetoacetoxy decorated shell polymer through the ketoamine reaction. The metathesis reaction of aromatic disulfides in the crosslinking segments enabled the thermally induced dynamic behavior of the network as revealed in the stress relaxation tests by comparison with other diamine crosslinking agents without the incorporation of disulfide. The synergism of the dynamic crosslinking of the shell polymer and static crosslinking in the core polymer contributed to the improved mechanical strength (15 MPa, strain% = 250%) and the suppressed water adsorption (~1% in 24 h of soaking) of the latex film, which exhibited above 90% of recovery in both strength and strain from a cut-off film damage within 1 h at 80°C. Moreover, the cured latex film could be recycled, and 75% of the mechanical performance was regained after three fragmentation-hot-pressing cycles. These, in addition with the feasible and environmental friendly characteristics, suggest a sustainable paradigm toward the smart thermosetting latex polymers. Graphical
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
危险品化学品经营许可证（带存储）