CONSTRUCTION AND BUILDING MATERIALS
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2025
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IF 8
Yujie Wang,Xili Yan,Kenan Li,Siqi Li,Tao Ai,Fengrong Shi
Conventional epoxy asphalt is difficult to reuse due to its thermosetting inability to heal and reprocess. In this study, using dimer acid (DA) and zinc acetate (Zn(OAC) 2 ) as curing agent and catalyst, respectively, and the hydroxyl-ester bonds were introduced into the dynamic crosslinking network system of the asphalt, a highly compatible epoxy asphalt DEA with heat recovery performance was designed. On this basis, the effects of different contents of capped hyperbranched polyester HP102 on the mechanical properties, low-temperature properties, and compatibility of DEA were investigated. The results showed that the base asphalt was successfully grafted with hydroxyl and ester groups, and this chemical modification effect reduced the polarity between the asphalt phase and the resin phase, resulting in a notable improvement in the compatibility of DEA compared with commercially available epoxy asphalt. The introduced HP102 improves not only the low-temperature ductility of the material but also its structural presence of -COO- groups, which can be further used to realize the dynamic exchange and reorganization of hydroxyl-ester bonds, which contributes to the modulus relaxation of the material and enhances its mechanical properties and self-healing ability. The highly branched structure of HP102 increases the unoccupied space and undergoes stress relaxation, which contributes to the improvement of the low-temperature ductility of the material. In addition, the cyclic tensile test results show that the mechanical property recovery rate can reach 86.7 % when hot-pressing processed at 180 °C for 5 h, which confirms that the epoxy asphalt under the reversible covalent crosslinking network possesses non-negligible recycling potential, and provides an engineering application reference for the hot-pressing recycling of epoxy asphalt.
研究领域:
材料科学
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化学工程
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道路工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Polymer Materials
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2025
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IF 4.7
Lingfeng Cui,Jing Qiao,Guanyue Zeng,Yuzhu Xiong,Gege Huang,Daiqiang Li
Developing biobased rubber composites that simultaneously boost tensile strength and elongation at break while integrating self-healing capacity and reprocessability remains a critical challenge in the rubber industry. Inspired by the unique multiple hydrogen bonding structure of spider silk and the dynamic β-hydroxy ester exchange reaction, this study constructed an epoxy polyurethane rubber containing octuple hydrogen bonds and incorporated it into epoxidized natural rubber. Carboxylated silica was utilized as a bridging agent to form β-hydroxy ester reversible covalent bonds at the interface between the filler and the rubber, thereby designing a high-strength, self-repairing, and reprocessable’vitrimer’ biobased elastomer. This design approach endows the material with outstanding mechanical properties (tensile strength of 8.92 MPa, Young’s modulus of 2.71 MPa, toughness of 17.45 MJ/m3), excellent self-healing performance (healing efficiency of 92.1%), and superior processability (tensile strength recovery of 97.6%). These properties are primarily attributed to the presence of reversible noncovalent octet hydrogen bonds and dynamic covalent β-hydroxy ester bonds. Furthermore, this design can be readily implemented across different biobased epoxy polymers and carboxyl-rich nanofillers. The design concepts presented herein can be applied to the development of self-healing and reprocessable’vitrimer’ biobased elastomers, providing valuable insights for the future design of green and sustainable polymers.
研究领域:
材料科学
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高分子化学
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绿色化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
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2025
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IF 9.5
Zhimin Kou,Ye Sha,Meiting Liu,Guixin Zhang,Jie Wang,Meng Zhang,Lihong Hu,Puyou Jia,Yonghong Zhou
The intelligent design and green manufacturing of bio-based adhesives still face severe challenges. In this study, an epoxy adhesive based on β-hydroxyester bonds and multiple hydrogen bonds was prepared using tung oil and lignin. Molecular dynamics simulation was used to regulate the structure and properties of adhesives. The adhesive with a large number of aromatic ring structures and phenolic hydroxyl groups enhanced cohesion and surface adsorption through π–π stacking and hydrogen bonding. Conjugated double bonds and the flexible long chain of tung oil in the structural skeleton of adhesives provided modification sites and endowed the materials with good ductility. The adhesive materials showed remarkable mechanical properties, recyclability, and an adhesive strength of approximately 6 MPa, enabling their effective use in various harsh environments, with a decrease in shear strength of only about 10%. Two adhesive models, one with β-hydroxyester bonds and multiple hydrogen bonds and the other without these structures, were established for comparison. The adhesion energy on the wood surface was calculated to assess the impact of each structural component in the system. In this study, a strategy to analyze the interplay between the microstructure and properties of adhesives was presented, and a potential route for the intelligent design and manufacturing of high-performance bio-based adhesives was provided.
研究领域:
材料科学
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生物化学
✓ 已验证
产品关联
DOI
高影响因子
COMPOSITES SCIENCE AND TECHNOLOGY
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2019
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IF 6.309
Chuanhui Xu,Zhongjie Zheng,Wenchao Wu,Lihua Fu,Baofeng Lin
Thermosetting resin-based composites are applied widely, but they are insoluble and infusible once complete curing so that they may be wasteful when the materials have some damages. Here, we use a simple and efficient method to design an epoxy composite which can be healed and recycled via interesterification reaction at elevated temperature. Carboxylated cellulose nanocrystals (CCNs) with a large number of carboxyl groups on the surface were isolated from cotton by hydrochloric acid and nitric acid, and then were used as crosslinker to react with diglycidyl ether of bisphenol A (DGEBA). Fourier transform infrared (FTIR) spectroscopy result indicates that β-hydroxyl ester bonds were formed between carboxyl groups and epoxy groups , while the equilibrium swelling experiment result confirms the formation of β-hydroxyl ester bond-crosslinked networks. Interestingly, the char yields of composites (>16%), much higher than that of CCNs (7.05%) and DGEBA (4.44%), were about three times higher than the calculated values, showing a significantly improved thermal stability. It was found that the composite with a carboxyl/epoxy = 0.2 has a better and more obvious healing affect at 180 °C than others.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
EUROPEAN POLYMER JOURNAL
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2022
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IF 5.546
Yanning Zeng,Bin Yang,Zhaoyi Luo,Xianjie Pan,Zhao Ning
Bio-massed epoxy vitrimers are significant for sustainable industrial development, however, most of them show low mechanical properties and thermostability. The rosin derivates with rigid hydrophenanthrene framework have been synthesized as epoxy monomer and curing agent, for preparation of fully rosin-based epoxy vitrimer networks with dynamic β -hydroxy ester bonds. Meanwhile, to further improve mechanical properties and thermostability of the networks, zinc acetylacetonate was coordinated with the network by interaction of zinc metal with carbonyl group in the networks. The obtained fully rosin-based epoxy vitrimers have been characterized by FTIR, SEM, and DMA measurements. The obtained networks possess the higher mechanical properties (tensile strength = 40.8 MPa, toughness = 10.77 MJ/m 3 ) and thermostability ( T 5d = ∼270 °C) than these of vegetable oil-based epoxy vitrimers. Moreover, the performances of thermo-healing, welding, shape memory, physical and chemical recycling have been investigated. Present results demonstrate obtained epoxy vitrimers with good functionalities. In addition, fully rosin-based epoxy vitrimers display an excellent degradability under ethylene glycol solvent and can be applied as environmentally friendly materials.
研究领域:
材料科学
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可持续化学
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高分子科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Polymer Materials
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2025
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IF 4.7
Hao Wu,Xing Guo,Ming-Chao Luo,Shuangquan Liao
Dynamic covalet networks, exemplified by Vitrimers, hold significant promise for sustainable polymers due to their reprocessability and mechanical robustness. However, their susceptibility to creep deformation under sustained stress, driven by dynamic bond mobility, limits practical utility. We report a multiphase Vitrimer elastomer based on transesterification. Two distinct carboxylic acid cross-linkers containing dynamic β-hydroxy ester bonds were highly cross-linked into epoxidized natural rubber (ENR). Dithiodibenzoic acid (DS) bearing benzene rings first undergoes preferential aggregation via π–π interactions and thermally cross-links with epoxy groups to form a rigid hard phase, thereby restricting chain slippage and rearrangement at service temperatures to enhance creep resistance. Concurrently, 3,3′-dithiodipropionic acid (DD) establishes a soft phase with epoxy groups in the matrix, while preserving the material’s reprocessability. Stress relaxation and creep tests reveal that the hard domains/regions within the heterogeneous network structure impede segmental relaxation at relatively low temperatures, thereby enhancing the material’s creep resistance. At elevated reprocessing temperatures, however, these hard domains maintain dynamic bond exchange and segmental mobility, while the soft phase facilitates material reprocessability. This work establishes a scalable design framework for Vitrimers that synergistically enhances creep resistance and recyclability, addressing critical demands for durable yet sustainable engineering materials.
研究领域:
高分子科学
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材料工程
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可持续化学
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材料力学性能
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自修复材料
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
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2025
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IF 3.9
Chen Bingshen,Xia Biao,Liao Shijie,Zeng Daiwei,Lin Tengfei,Wen Na,Gao Min,Zhao Chunlin,Wu Xiao,Lin Cong,Zheng Xiaochun,Gao Fei
Two-way shape memory polymers (2W-SMPs), which can transition between two distinct temporary shapes, have garnered significant attention from researchers. This study successfully developed thermadapt 2W-SMPs using syndiotactic 1,2-polybutadiene (SPB) by leveraging dynamic covalent crosslinking techniques. Initially, m-chloroperbenzoic acid (m-CPBA) was employed for the epoxidation of SPB. Cysteine (Cys) was subsequently introduced to form a dynamic covalent bond of β -hydroxy ester via the reaction between the epoxy groups on SPB and the carboxyl groups of Cys. The sulfhydryl groups of Cys can undergo oxidative coupling to form disulfide bonds, thereby establishing two distinct types of dynamic covalent bonds within the material and lowering its topological rearrangement temperature. Through the exchange reactions of these dynamic covalent bonds at elevated temperatures, the resulting material exhibits enhanced mechanical properties and can be reshaped in the solid state. This work provides a viable method for preparing recyclable thermally adaptive 2W-SMPs under stress-free conditions, thereby enriching the research landscape in the field of shape memory materials.
研究领域:
材料科学
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高分子化学
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智能材料
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形状记忆聚合物
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动态共价化学
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可回收材料
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
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2024
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IF 8.3
Xiaoyu Huang,Chen Ding,Yichun Wang,Songmao Zhang,Xiuhui Duan,Hongzeng Ji
Novel reprocessable thermosetting adhesives (RTAs), which combine high adhesive strength, reusability, disassembly, and recyclability features, have attracted increasing attention. However, developing RTAs with a rapidly adhesive rate while ensuring high adhesive strength and self-healing ability is still a significant challenge. Here, we prepared a novel vitrimer called DAx–DTSAy, which can be used as an RTA. First, by adjusting the ratio of rigid and flexible segments, maximum tensile strength reached 35.92 MPa. Second, the combined effect of dynamic hydroxyl ester bonds and dynamic disulfide bonds resulted in a rapid stress relaxation behavior, with a complete relaxation time 13.6 times shorter than a vitrimer only cross-linked with hydroxy ester bonds. This feature endowed its good self-healing and reprocessing capabilities. After self-healing at 180 °C, the maximum healing rate of mechanical properties was 91.8%. After three reprocesses, the maximum recovery rate of tensile strength was 120.2%. Furthermore, the combination of rigid and flexible segments and the synergistic effect of dual dynamic covalent bonds made DAx–DTSAy capable of use as a high-performance RTA. The lap shear strength of a DAx–DTSAy film on stainless steel reached 18.18 MPa after 15 min, with a recovery rate of 91.9% after 5 rebonding cycles. Additionally, DAx–DTSAy can be disassembled in chemical agents and exhibited better insulation properties compared to traditional epoxy resins. DAx–DTSAy can be employed as a novel high-performance adhesive in applications such as electronic devices and transportation, contributing to the development of thermosetting adhesives toward recyclability and sustainability.
研究领域:
材料科学
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化学工程
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粘合技术
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聚合物化学
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可持续材料
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）