CERAMICS INTERNATIONAL
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2020
·Vol. 47
·期 7
·9083-9089
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IF 3.83
Hongli Liu,Lantian Zhang,Jing Li,Hongyan Li,Guoqing An,Yajing Li,Zhong Chen
SiBCN ceramic aerogels have excellent properties such as ultra-high temperature stability, low density and high thermal insulation . The aerogels have better potential applications in aerospace and other fields. However, similar to inorganic aerogels , the low mechanical strength of SiBCN ceramic aerogels are the main limitation of its application. Based on the principle of inorganic double network enhancement, the first network was constructed by PVA and HNTs , and HNTs/SiBCN dual network aerogels were constructed by SiBCN ceramic aerogels as the second network. The structure and mechanical properties were characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), specific surface area analyzer and pressure tester. Compared with SiBCN ceramic aerogels, 6 wt% HNTs-SiBCN ceramic hybrid aerogels have better microscopic properties (maintaining basic porous network structure and structural stability) and mechanical properties.The continuous HNTs first network can effectively transfer the stress load and enhance the strength of SiBCN ceramic aerogels.
研究领域:
材料科学
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无机非金属材料
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纳米复合材料
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航空航天材料
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高分子复合材料
✓ 已验证
DOI
高影响因子
POLYMER
·
2018
·
IF 3.483
Haofei Li,Hongbo Wang,Dongfei Zhang,Ziyang Xu,Wenguang Liu
Recently, we have constructed a high strength and thermoplastic supramolecular poly( N -acryloyl glycinamide) (PNAGA) hydrogel which can be developed as printable bioinks. However, the PNAGA hydrogel is low in stiffness and toughness, potentially limiting its application as load-bearing soft tissue scaffolds. In this work, we fabricate a supramolecular polymer double-network hydrogel based on hydrogen bonding crosslinked PNAGA and Fe 3+ -coordination crosslinked sodium carboxymethyl cellulose (CMC). The combined hydrogen bonding and ionic crosslinks contribute to high-strength nonswellable PNAGA/CMC-Fe hydrogels (Tensile strength of 2.9 MPa and compressive strength of 7.3 MPa at 80% strain without fracture) and stiffness (Young's modulus of 1.2 MPa and compressive modulus of 1.5 MPa). Furthermore, these reversible double physical crosslinks enable the PNAGA/CMC-Fe hydrogels to dissipate energy efficiently with a high toughness (12.3 MJ m −3 ) and tear energy (3700 J m −2 ), meanwhile imparting self-recoverability, anti-fatigue ability and self-healability to the network. This cytocompatible supramolecular polymer double network hydrogel with excellent multifaceted mechanical performances are promising to exploited as load-bearing soft tissue engineering scaffolds .
研究领域:
生物材料学
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组织工程
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高分子科学
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再生医学
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生物力学
✓ 已验证
DOI
高影响因子
POLYMER
·
2019
·
IF 3.771
Feng Chen,Ziqing Tang,Shaoping Lu,Lin Zhu,Qilin Wang,Qin Gang,Jia Yang,Qiang Chen
Double network hydrogels (DN gels) are one of most extensively investigated high strength hydrogels. However, most of DN gels are concern to macromolecules , low-molecular-weight gelators (LMWG)-based supramolecular hydrogels are rarely reported to fabricate recoverable DN gels. Owing to the low mechanical properties, LMWG-based supramolecular hydrogels are hardly fabricated as conductive materials for human motion monitoring. Herein, we report a general strategy to fabricate strong, tough and conductive cholate-based supramolecular gels with double network (DN) structure (i.e. La-cholate/PAAm DN gels), consisting of La-cholate supramolecular gel as first network and covalent polyacrylamide gel (PAAm gel) as second network, in which La-cholate supramolecular gel was self-assembled by La 3+ ions and sodium cholate under sonication via the synergistic effect of hydrogen bonds , hydrophobic interactions and metal-coordination. At optimal condition, La-cholate/PAAm DN gel exhibited high tensile properties (fracture stress of 0.314 MPa, fracture strain of 29.85 mm/mm, elastic modulus of 90 kPa, and work of extension of 5.678 MJ/m 3 ) and high toughness (tearing energy of 1098 J/m 2 ), which are comparable to conventional chemical or hybrid DN gels. Meanwhile, La-cholate/PAAm DN gel also showed rapid self-recovery property (stiffness recovery of 84% and toughness recovery of 46% after resting for 3 min) at room temperature and λ-dependent luminescent property under UV-light. More importantly, cholate-based supramolecular gels with DN structure could be prepared with various metal ions and monomers . Interestingly, our cholate-based DN gels were ionically conductive, which could be used as strain sensor to finely detect the human motions. We hope our design principles, along with the simple method and cholate-based DN gels, can be generally applied to develop a new generation of strong and tough LMWG-based supramolecular hydrogels with various functionalities.
研究领域:
高分子科学
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生物材料
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软物质物理
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纳米医学
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组织工程
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智能响应材料
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生物传感
✓ 已验证
DOI
高影响因子
JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS
·
2018
·Vol. 56
·期 19
·1281-1286
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IF 2.499
Yan Jie Wang,Chen Yu Li,Zhi Jian Wang,Yiping Zhao,Li Chen,Zi Liang Wu,Qiang Zheng
Development of tough hydrogels has greatly expanded their applications as load-bearing materials. However, the elastic modulus of tough hydrogels is usually lower than 1 MPa. It remains a challenge to design tough hydrogels with high modulus. We report here a series of tough double-network (DN) hydrogels with ultrahigh elastic modulus (up to 200 MPa) by forming robust hydrogen bonds between the first poly(acrylic acid) network and the second poly( N -isopropyl acrylamide) network. The dense cooperative hydrogen bonds greatly reduce the segmental mobility and thus improve the rigidity of gel matrix. Owing to the dynamic nature of hydrogen bonds, the modulus of hydrogels is strongly influenced by temperature and pH, affording the gels shape memory property. The strategy by forming robust noncovalent bonds between interpenetrating networks should be applicable to other systems for designing tough and versatile hydrogels with diverse promising applications. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018 , 56 , 1281–1286
研究领域:
高分子物理
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生物材料
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软物质科学
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智能响应材料
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组织工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）