MACROMOLECULAR CHEMISTRY AND PHYSICS
·
2023
·Vol. 224
·期 24
·2300359
·
IF 2.5
Kuan Zhang,Lin Dang,Junliang Zhang
Silicone rubbers are widely employed in various fields such as electronics, electrical engineering, mobile communications, aerospace, and automotive industries. However, silicone rubbers are typically challenging to reprocess and degrade. Moreover, with the advancement of technology, higher demands are placed on its thermal conductivity and dielectric properties. In this study, diglycidyl ether terminated polydimethylsiloxane is cured by 4,4′-dithiodibutyric acid which contains dual dynamic covalent disulfide and ester bonds with triazobicyclodecene as the ester exchange catalyst to prepare silicone rubber vitrimers (SRVs) through a casting method. The SRVs demonstrate a relatively higher intrinsic thermal conductivity of 0.26 W (m⁻ 1 K⁻ 1 ) compared to ≈0.20 W (m⁻ 1 K⁻ 1 ) of conventional silicone rubber. Besides, the SRVs exhibit very low and stable dielectric constant and dielectric loss at both low and high frequencies (X-band). The lowest dielectric constant and dielectric loss tangent at 10 GHz are 2.75 and 0.0650, respectively. Besides, the dual dynamic covalent bonds enable the SRVs to have excellent reprocessability and fast degradability. Moreover, the SRVs reveal UV-shielding capability, as the transmittance of the SRVs is 0% from 200 to 400 nm of UV light.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
Polymers
·
2025
·Vol. 17
·期 17
·2387
·
IF 4.9
Haidan Lin,Kai Dong,Jingyao Luan,Chenggang Li,Di Zhao,Chengji Zhao,Xuefeng Li
Developing high-performance bio-based epoxy resins as sustainable alternatives to petroleum-derived bisphenol A (BPA) epoxies for recyclable carbon fiber-reinforced polymers (CFRPs) is pivotal in materials research. Herein, the bio-based bisphenol monomer BDEF was synthesized from the lignin derivative 4-propylguaiacol. The derived epoxy monomer BDEF-EP was cured with adipic acid to form a bio-based vitrimer. Stress relaxation synergistically accelerates through intrinsic dynamic carboxylic acid ester exchange and enhanced chain mobility from the flexible propyl structure. At 220 °C, this vitrimer shows rapid stress relaxation (τ* < 30 s) and repairs ~90% of surface scratches in 30 min. It exhibits tensile and flexural strengths of 69 MPa and 105 MPa, respectively. BDEF-EP’s low viscosity reduces diluent needs in composite fabrication, lowering costs and improving efficiency. The resulting bio-based CFRP achieves tensile and flexural strengths of 543 MPa and 414 MPa, respectively, which are comparable to commercially available petroleum-derived CFRP. In addition, CFRP containing dynamic crosslinked networks demonstrates degradable recyclability in ethylene glycol solvent, preserving the surface morphology and chemical structure of recovered carbon fibers. The results demonstrate that this bio-based epoxy vitrimer has promising potential for developing sustainable, degradable, and recyclable CFRP composites.
研究领域:
材料科学
·
高分子化学
·
可持续工程
·
复合材料技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Kai Zhao,Yunpeng Wang,Jingyu Guo,Shufen Zhang,Wenbin Niu
Flexible and stretchable electronics with mechanosensory functionality are highly desirable on account of their intriguing applications in smart wearable devices. Unfortunately, the susceptibility to structural damage and single electrical signal output restrict their further practical uses. Here, novel photonic vitrimer-based electronics (PVBEs) with self-healability and ultrastable visual-digital outputs are developed by harnessing vitrimer-induced structural evolutions of both photonic crystal (PC) and piezoresistive carbon textile. They demonstrate excellent strain sensing performances including synchronous electrical/optical response (0.25 s), high sensitivity (gauge factor, GF = 10.3), superior durability (>10000 cycles) and mechanochromism. Notably, dynamic covalent networks within vitrimer endow them self-healing ability of optical function, while the electromechanical performances are stably maintained benefiting from unique fully-embedded structure. Based on these merits, a new type of PVBE is demonstrated by incorporating wireless transmission system. Such a device can function as wirelessly visualized sensor for real-time tracking both large and subtle human movements with optical and electrical dual-signal feedbacks, realizing remote and precise visual-digital outputs. This work offers a versatile platform for emerging self-healing functional devices and visually interactive electronics, bringing huge developments in the era of the Internet of Things.
研究领域:
材料科学
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电子工程
·
智能设备
✓ 已验证
DOI
高影响因子
ACS Applied Polymer Materials
·
2025
·
IF 4.7
Shibiao Chai,Yixin Fang,Zhi Chen,Dehuan Kong,Shuangfei Xiang,Shujun Zhao,Feiya Fu,Xiangdong Liu
The development of biobased epoxy vitrimer materials aligns with environmental sustainability. However, constructing fully biobased dynamic cross-linking networks that integrate mechanical, reprocessability, and degradability remains a significant challenge. In this work, a fully biobased epoxy vitrimer with a disulfide bond-decorated dynamic covalent network was developed using biomass-derived diphenolic acid and cystamine. Diphenolic acid underwent an amidation reaction with cystamine, followed by epoxidation to form an epoxy monomer, which was further cured with cystamine to obtain fully biobased epoxy vitrimers. The as-prepared epoxy vitrimers exhibited excellent mechanical properties and thermal stability, attributed to the high cross-linking density and topological interlocking structure induced by amidation. The dynamic cross-linking network endowed the epoxy vitrimers with good self-healing and reprocessability through disulfide bond exchange reactions, while the disulfide bonds could enable degradability when treated with dithiothreitol. When epoxy vitrimers were used as a matrix to form carbon fiber-reinforced composites, the obtained composites exhibited a tensile strength exceeding 613.53 MPa. The resin matrix could be completely degraded in 2.5 h without compromising the structure or properties of the carbon fibers. This work offers insights into the design of fully biobased epoxy vitrimers and their carbon fiber composites.
研究领域:
材料科学
·
环境科学
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产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2024
·Vol. 141
·期 42
·e56101
·
IF 2.7
Zhengping Chang,Yazhi Gao,Kanghe Yan,Zhongqi Wang,Menglin Zhao,Yang Zhao
The resin is a fundamental factor in determining the performance and usage conditions of its composites. The epoxy vitrimer, which combines both thermoplastic and thermosetting properties, shows significant potential in extending the service life of material. The curing process significantly affects the macroscopic properties of the vitrimer and the resulting carbon fiber reinforced plastics (CFRP). Effective control of curing parameters constitutes the critical factor for the assurance of product quality. In the study, a differential scanning calorimetry (DSC) was utilized to establish a curing kinetics model for a modified, self-healable epoxy vitrimer based on transesterification. Then the molecular structure, thermodynamic, and mechanical properties of the cured vitrimer were analyzed. Next vitrimeric CFRP (vCFRP) laminates were fabricated, and the tensile and bending properties of the vCFRP laminates were investigated. The results showed the curing process was obtained: 95°C/1 h + 150°C/2 h + 170°C/2 h. The thermodynamic and mechanical properties of cured vitrimer could meet practical requirements. The minimal differences observed in the stress–strain curves of the specimens indicated that the curing process was appropriately configured. The prepared laminates exhibited performance comparable to that of commercial thermosetting composites.
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 POLYMERS AND THE ENVIRONMENT
·
2024
·
IF 4.7
Zhao Yanna,Zhang Yingying,Bai Xiaowei,Wang Yuqi,Hou Wentong,Huang Yuqing
Conventional epoxy anhydride curing systems typically require large amounts of catalyst to ensure a high ester exchange rate, and the resulting cured epoxy vitrimer has renewable and self-repairing properties, but is limited by the amount of catalyst loading. In this study, a diol (VT) containing imine bonds was synthesized from vanillin (VAN) and tyramine (TA) to catalyze the epoxy-anhydride curing process, and glycerol triglycidyl ether (GTE) was co-cured with VT and methylhexahydrophthalic anhydride (MHHPA), which constructed a bio-based regenerative and repairable epoxy vitrimer with dual dynamic covalent bonds (GMV), the free hydroxyl groups in the crosslinked network could rapidly promote the ester exchange rate. The thermal, mechanical, solvent resistance, self-repairing, renewable and shape memory properties of GMV were systematically investigated by adjusting the ratio of anhydride and hydroxyl groups. It exhibits a better thermal stability property T d 5% (281.27℃) and a shorter relaxation time τ (12.15 s) at 140 °C. In addition, the scratches of GMV could be almost completely healed at 120 °C for 60 min, and this test demonstrated that GMV has better self-healing and renewable tests. The present work promotes the epoxy vitrimer species and expands the esterification scheme performed without catalyst.
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
MACROMOLECULES
·
2024
·
IF 5.1
Nianzhao Gao,Yanglei Zheng,Jianan ShangGuan,Haoran Sun,Junyi Jiang,Shuangfei Xiang,Shujun Zhao,Feiya Fu,Xiangdong Liu
The development of sustainable composites necessitates biobased epoxy resins that are highly recyclable and degradable; however, the integration of mechanical, reprocessing, and rapid degradation properties into a single epoxy resin remains a significant challenge. The present study proposes a straightforward approach to overcoming the problem by combining two labile covalent bonds into an epoxy resin. The combination of acetal and disulfide bonds demonstrates a synergistic effect on the degradation performance of epoxy resin, leading to an ultrafast degradation of the epoxy polymer. The carbon fiber-reinforced composite with the epoxy resin matrix shows a tensile strength exceeding 630 MPa, but the epoxy resin degrades completely within just 8 min, while the recovered carbon fibers display nondestructive characteristics similar to those of the original material. Moreover, the epoxy resin that we designed shows good self-healing and reprocessing ability. Scratches on the resin surface can be completely self-healed by heating, while the powdered resin can be reshaped under a hot press. These findings offer a new approach to the preparation of sustainable composites, highlighting the significant importance of the development of thermosetting polymers.
研究领域:
材料科学
·
可持续发展
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Polymer Materials
·
2024
·
IF 4.4
Pengyun Tan,Xiaotong Zhao,Zengshuai Zhang,Wuji Wei,Jiahao Zhou,Yingqing Shao,Xiaojing Ma,Shuangying Wei,Zhenhua Gao,Shuaiyuan Han
Self-healing materials are the current focus of smart materials research. However, the implementation of self-healing materials remains limited by the challenge of balancing efficient healing properties with high mechanical strength. In this study, N,N′-(4-hydroxy-3-methoxybenzyl) aniline (VPSB) with π–π conjugated structures were prepared by introducing Schiff base bonds between aromatic rings. VPSB is then incorporated into the polyurethane system to synthesize a self-healing waterborne polyurethane vitrimer (VPSB-WPU) containing conjugated aromatic Schiff base bonds. This locally conjugated structure can convert absorbed visible light into thermal energy, which promotes the rapid breaking and formation of Schiff base bonds, resulting in an improved self-healing effect. The results indicated that the topological network of the vitrimer exhibited an activation energy (Ea) of 60.69 kJ/mol and a freezing transition temperature (Tv) of 45.46 °C. After 3 min of visible-light irradiation, the film temperature increased from 6.4 to 91.5 °C, with a photothermal conversion efficiency of 92.13% and a film scratch-healing efficiency of 93.75%. After 25 min of irradiation, the fractured film’s tensile strength after healing was 11.57 MPa. These results demonstrated that VPSB-WPU exhibited vitrimer properties and possessed excellent mechanical strength, photothermal conversion, and self-healing function. A balance between highly efficient healing properties and excellent mechanical strength was achieved by the VPSB-WPU vitrimer, making it highly promising for future applications in material self-healing.
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
POLYMER
·
2022
·
IF 4.432
Lin Wang,Yingjun Liu,Na Hao,Yunhe Qiao,Wanting Zeng,Liping Wei,Aihua Du
Vitrimers circumvent the trade-off between the covalent crosslinking and malleability for polymers, making them ideal candidates for the design of reconfigurable polymer networks . However, it's extremely arduous to access elastomer vitrimers both strong in strength and creep resisting at service. Herein, to solve this conundrum, we have designed and synthesized a series of vitrimer networks by combining multiple hydrogen bonds (H-bonds) and boronic ester bonds into styrene butadiene rubber (SBR). Particularly, SBR is firstly modified by 2-ureido-4-[1H]-pyrimidinone (UPy) and subsequently crosslinked by dimercapto-borate. With a combining of π-π stacking of the UPy rings and the lateral multiple H-bonds between two ureidos in structure, the grafted UPy moieties tend to aggregate to form microphase separated structure. UPy aggregations are functional as sacrificial units and enhance the strength of the rubber vitrimers through reversible breaking and reforming events. Moreover, the UPy aggregations in hard domains make the segment mobility more confined and retard the topology rearrangement, as a result, the dimensional stability at service temperature is elevated. However, the malleability of the rubber vitrimers is hardly affected as the UPy aggregations are dissociated at elevated temperatures.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
COMPOSITES SCIENCE AND TECHNOLOGY
·
2022
·
IF 9.879
Yazhou Xu,Haibo Zhang,Songlin Dai,Shichao Xu,Jing Wang,Liangwu Bi,Jianxin Jiang,Yuxiang Chen
Closed-loop recycling in the matrix resin and carbon fibers (CFs) of carbon fiber-reinforced polymers (CFRPs) is a major challenge. To solve this problem, herein, a closed-loop recyclable vitrimer matrix containing hydroxy-terminated hyperbranched polyesters (HBPs), rosin-derived fumaropimaric acid (FPA), and glycerol triglycidyl ether (GTE) is prepared. The FPA/GTE/HBP vitrimers exhibited excellent mechanical properties owing to the highly reactive hydroxy-terminated HBP and rigid FPA. The abundant hydroxyl groups of HBP catalyzed the dynamic transesterification reaction of the vitrimer network, resulting in self-healing and reprocessing properties. In addition, FPA/GTE/HBP−CF composites exhibited high mechanical strength and interlayer shear strength owing to the presence of HBP. FPA/GTE/HBP 15 −CF was degraded by ethylene glycol during the catalytic operation of the hydroxy-terminated HBP, and the degraded matrix could be closed-loop recycled. Scanning electron microscopy, Raman analysis, and tensile testing showed that the degradation reaction did not degrade the properties of the recycled CFs. This study presents an environmentally-friendly strategy for preparing closed-loop recyclable CFRPs.
研究领域:
材料科学
·
聚合物化学
·
可持续材料
·
复合材料
·
回收技术
✓ 已验证
产品关联
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2022
·
IF 10.723
Chang Li,Benzhi Ju,Shufen Zhang
Catalyst-free fully bio-based hydroxyester (BHE) vitrimers were synthesized by crosslinking and plasticizing epoxidized soybean oil with synthesized acetylated starch succinate monoesters to investigate the effects of different starch structures on the properties of the BHE vitrimers. The BHE vitrimers possessed a lower glass transition temperature as well as better solvent resistance and reprocessing performance compared to traditional starch-based materials. Owing to dynamically covalent bonds , the migration and exudation of plasticizers were avoided. A maximum strain of 230 % was achieved to prevent the retrogradation and brittleness of starch-based materials. Furthermore, the mechanical properties remained unchanged after three reprocessing cycles. Consequently, the obtained BHE vitrimers are eco-friendly and sustainable.
研究领域:
材料科学
·
化学工程
·
生物技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
POLYMER TESTING
·
2022
·
IF 4.931
Chumeng Luo,Wei Yang,Wen Qi,Zilong Chen,Jun Lin,Xingming Bian,Shaojian He
Epoxy (EP) vitrimer with excellent processing and recyclability is of great potential for industrial application. In this study, we prepared an EP vitrimer based on the low viscosity homogenous mixture of diglycidyl ether of bisphenol A (DGEBA) and a liquid hardener dimethyl 3,3′-dithiodipropionate (DTDP) catalyzed by 2,4,6-tris (dimethylaminomethyl) phenol (DMP30). The optimal curing condition was determined to be 110 °C × 12 h for the original EP vitrimer. Owing to the exchangeable disulfide crosslinks, rapid stress relaxation was found for the vitrimer with a relaxation time of 1.9 s at 160 °C. Moreover, the prepared EP vitrimer possessed excellent self-healing ability and recyclability, with recovery ratio of at least 94.1% during 3 times recycling. The self-healing ability, recyclability and processing performance remain excellent for the vitrimer even after incorporating 30 wt% boron nitride (BN), which can be recycled using DMF as a solvent.
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
危险品化学品经营许可证（带存储）