MACROMOLECULAR RESEARCH
·
2021
·Vol. 29
·期 8
·562-568
·
IF 2.227
Wei Zhengkai,Wang Yi,Fu Xiaowei,Jiang Liang,Wang Yuechuan,Yuan Anqian,Xu Hualiang,Lei Jingxin
The thermosetting polyurea possessed high tensile strength and elongations at break due to strong intermolecular interactions, but their recycling and reprocessing remains a great challenge, especially at a temperature below 100 °C. Herein, the novel crosslinked polyurea with excellent recycling and reprocessing properties has been prepared by introducing the Diels-Alder dynamic covalent bond. The chemical structure, thermal mechanical properties and reprocessing performance of the crosslinked polyurea were investigated. The prepared polyurea has low relaxation time of ∼4 min at 80 °C for facile reprocessing. The tensile strength and elongation at break of crosslinked polyurea could reach 15.24 MPa and 529.2%, respectively, and its mechanical properties remain almost unchanged even after repeated processing. This work has realized the recycling of crosslinked polyurea, which has huge potential applications in environmental protection and recycling of waste plastics.
研究领域:
材料科学
·
聚合物化学
·
环境科学
✓ 已验证
DOI
高影响因子
Polymers
·
2023
·Vol. 15
·期 5
·1270
·
IF 5
Haiyan Mao,Qun Zhang,Ling Lin,Xuemei He,Lili Wang
Polyurethanes with self-healing and reprocessing capabilities are promising in eco-friendly applications. Here, a self-healable and recyclable zwitterionic polyurethane (ZPU) was developed by introducing ionic bonds between protonated ammonium groups and sulfonic acid moieties. The structure of the synthesized ZPU was characterized by FTIR and XPS. The thermal, mechanical, self-healing and recyclable properties of ZPU were also investigated in detail. Compared with cationic polyurethane (CPU), ZPU shows similar thermal stability. The physical cross-linking network formed between zwitterion groups can dissipate strain energy as a weak dynamic bond, endowing ZPU with outstanding mechanical and elastic recovery properties, including the high tensile strength of 7.38 MPa, high elongation at a break of 980%, and fast elastic recovery ability. Additionally, ZPU exhibits a healing efficiency of over 93% at 50 °C for 1.5 h as a result of the dynamic reconstruction of reversible ionic bonds. Furthermore, ZPU can be well reprocessed by solution casting and hot-pressing with a recovery efficiency above 88%. The excellent mechanical properties, fast repairing capability, and good recyclability not only enable polyurethane with a promising application in protective coatings for textiles and paints but also make it a superior candidate as stretchable substrates for wearable electronic devices and strain sensors.Keywords:zwitterionic polyurethane;elasticity;self-healing;reprocessing
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
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Yuanhao Ma,Haoxiang Rong,Yanan Zhang,Xun Lu
Achieving robust, high elasticity, transparency, self-repairing, reprocessability and durability simultaneously remains a huge challenge. In this work, we propose a simple strategy to prepare an ultra-high strength, outstanding elasticity, self-repairing and reprocessable poly (thiourethane-urea) (PTUU) film based on interlocking hydrogen bonds (IHBs) and reversible topological networks. The IHBs between its main chains make it have ultra-high tensile strength (61.6 MPa) and good scratch resistance. It is the highest tensile strength ever recorded for crosslinked self-repairing materials at medium temperature thus far. The synergistic effect of IHBs and topological networks makes it high elasticity and can repair more than 90 % of the mechanical strength. Rearrangement of reversible topology network at high temperature endows PTUU with reprocessability, and the mechanical strength remains more than 85 % after reprocessing for three times. In addition, PTUU films have high transmittance (96.6 %, 0.5 mm), low haze, high refractive index and excellent durability, which have broad application prospects in transparent protective materials, optical lenses, stretchable fibers, wearable electronic devices and other fields.
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
MICROCHEMICAL JOURNAL
·
2025
·
IF 5.1
Juan Liu,BiYa Gong,Ping Zhang,JuanJuan Wu,Chun Yi,ChunMei Wang,YouHan Kong
Chinese bayberry ( Morella rubra Lour ) is a fruit from the Myricaceae family, rich in various dietary nutrients, and has a long history of cultivation and use in both food and medicine. The diversity of Chinese bayberry resources and its perishable nature limit its reprocessing and long-distance sales, posing challenges for the industry. This study compared the decay resistance characteristics, soluble solids, organic acids, and apparent traits of six different Chinese bayberry resources in Hunan Province, evaluating their edibility and processing characteristics. Using LC-MS and GC–MS, the non-volatile and volatile components of the six types of Chinese bayberry were extensively identified. The results showed that different types of Chinese bayberry contain distinct metabolites, which are significantly correlated with their decay resistance and apparent traits. Compounds such as Mesuagin, Arctigenin, and Eugenin were directly related to the decay area ratio and fruit weight. Licoricidin and Naringenin may have potential relationships with decay resistance. In this study, we took bayberry from six different resources as an example and preliminarily demonstrated that there were significant differences in the decay resistance and apparent traits of different bayberry varieties, which were related to their internal metabolites. Several specific substances in bayberry that are directly related to the preservation and reprocessing characteristics of bayberry were identified. These substances may have the potential to become key potential markers for evaluating the processing and storage characteristics of bayberry.
研究领域:
食品科学
·
植物化学
·
代谢组学
✓ 已验证
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2024
·
IF 6.5
Chaoying Hu,Fanqi Liu,Zhaoyi Luo,Quanqian Yi,Yanning Zeng,Yunhua Chen,Chaoyang Wang
Biobased reprocessable polyurethane (PU) networks have drawn significant attention due to limited petroleum resources and aggravating environmental issues. However, the preparation of biobased PU networks with simultaneous efficient flame-retardant, antioxidative, self-healing and reprocessing performance is a great challenge due to the complicated structural design required. A novel strategy to fabricate multifunctional PU networks containing dynamic phenol–carbamate bonds from biobased naringenin and vanillin has been developed. First, a vanillin-based diol containing organic phosphorus moieties (VD) was prepared. Then modified diol and naringenin were combined to produce a self-healable, recyclable, antioxidative and flame-retarded PU (NVP-x)s where x represents the molar ratio of n[-OH (VD) ] / n{[-OH (naringenin) ] + [-OH (VD) ] + [-OH (PTMG) ]} possesses excellent flame-retardant, antioxidative, self-healing and reprocessing performance due to the presence of dynamic phenol–carbamate bonds, organophosphorus and phenolic moieties. An effective approach to the manufacture of multifunctional PUs with a potential application in the field of self-healing and flame-retardant coating, wound dressing membranes and fire-control engineering materials has been demonstrated.
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
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2024
·Vol. 35
·期 8
·e6547
·
IF 3.1
Xiao-qin Feng,Yi Wang,Xun Dai,Xiao-dong Liu,Yuan Liu
Flexible electronics are striving in modern society, and they impose harsh and urgent requirements for flexibility on electronic package substrates. However, traditional materials, including ceramics, metals, or polymers are lack of flexibility. Herein, a polyurethane named PU-D1Q1VF1 is proposed via incorporating carefully selected biobased units and synergistic dynamic bonds, and the PU-D1Q1VF1 not only meets the basic requirements of flexibility but also possesses properties of self-heal, UV-protection, reprocessability, and degradability. The polycaprolactone diol (PCL diol) was employed as the soft segment, and the bis(2-hydroxyethyl) disulfide (HEDS) and lignin derived model monomer hydroquinone were selected as chain extenders. Moreover, carefully synthesized bio-based monomer (E)-4-(((furan-2-ylmethyl)imino)methyl)-2-methoxyphenol (VF) was used as the capping agent, which could facilitate the self-healing process of the PU-D1Q1VF1.
研究领域:
材料科学
·
生物基材料
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2020
·
IF 3.99
Houchao Jing,Jianping Shi,Peipei Guoab,Shuang Guan,Hai Fu,Wei Cui
In this work, hydrogels based on polyvinyl alcohol (PVA), acrylamide (AM), calcium chloride, and ι-carrageenan were prepared via radical polymerization followed by freezing and thawing process. Comparing with pure PVA hydrogels, the obtained hydrogels possess higher tensile strength (1.54 MPa), Young’s modulus (92 kPa), and breaking energy (5.14 MJ/m 3 ) due to the synergistic effect of physical cross-linkers containing PVA crystallization, double helix structures of carrageenan and hydrogen bond. Furthermore, the tensile stress of the hydrogel is negligibly changeable after twenty successive loading-unloading tensile tests under different strain demonstrating good fatigue resistance. And the hydrogels can also be recast many times under high temperature, which is favorable for the reuse of materials. Besides, the directional motion of ions endows the hydrogels with electronic conductivity which is very sensitive to the strain deformation. Together with the good mechanical property the hydrogels may have the promising application in flexible sensors.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2024
·
IF 6.3
Tengfei Han,Benzhi Ju,Shufen Zhang
Despite covalent adaptable networks (CANs) imparting the reprocessing performance of crosslinked polymers, due to reversible bond exchange of the dynamic covalent bonds ; it is still a huge challenge to design catalyst-free, fast reprocessing, controlled degradation and raw material recycling biomass base CANs. Here, for the first time, we prepared cellulose CANs base on hemiacetal and acetal bonds (ACCs) via aldehyde and hydroxyl reaction of the dialdehyde crosslinker with hydroxypropyl cellulose (HPC). By regulating the crosslink density and chemical structure of the crosslinked network, ACCs exhibit tunable thermal and mechanical properties. The crosslinked network structure of the ACCs benefits from the rapid bond exchange of the hemiacetal and acetal bonds at elevated temperatures, which allows for rapid stress relaxation and thus, superior reprocessing properties. In addition, it was found that the dynamic exchange of acetals in the ACCs is influenced by the chain length and flexibility of the crosslinker. Moreover, ACCs possess good degradation and cellulose feedstock recycling properties due to the acid sensitivity of the acetal bonds. This work provides an effective solution to the problems of resource waste caused by petroleum-based thermoset plastics.
研究领域:
材料科学
·
化学工程
·
生物化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Pengwu Xu,Ning Ding,Hong Wang,Jieyu Guan,Yirui Shen,Deyu Niu,Weijun Yang,Piming Ma
Thermoset polyurethanes face significant deterioration of physical properties after damage self-healing or reprocessing. It is still a great challenge to design the structure of polyurethanes to realize damage self-healing and reprocess ability under mild conditions. In this work, a series of double-crosslinked networked polyurethanes with different crosslinking densities were synthesized by designing a synergistic crosslinking strategy of oxime-carbamate bonding and hydrogen bonding arrays. By regulating the density of the crosslinked network and the content of strong and weak hydrogen bonds, the tensile strength of the polyurethanes was increased from 13.1 to 24.3 MPa, and the toughness was increased from 66.5 to 129.2 MJ/m 3 . Meanwhile, the synergistic effect of the oxime-carbamate with low activation energy and hydrogen bonding arrays enabled the polyurethanes to have an excellent self-healing (97 %) and reprocessing. The polyurethanes could be rapidly reprocessed after only 5 min of hot pressing at 120 °C by virtue of the thermal response of the dual network. More importantly, the tensile strength retention rate can still maintain more than 96 % after reprocessing. Finally, we propose the concept of a wearable device that can intelligently detect changes in resistance values during human movement. Therefore, this work provides a new idea for the preparation of polyurethanes with excellent damage self-healing and reprocessing, which is expected to expand its application.
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
Minerals
·
2020
·Vol. 10
·期 9
·832
·
IF 2.38
Jie Wu,Jing Li,Feng Rao,Wanzhong Yin
In this study, copper slag reprocessing tailings (CSRT) were synthesized into geopolymers with 40%, 50% and 60% metakaolin. The evolution of compressive strength and microstructures of CSRT-based geopolymers in a marine environment was investigated. Except for compressive strength measurement, the characterizations of X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR) and scanning electron microscopy (SEM) were included. It was found that marine conditions changed the Si/Al ratio in the sodium-aluminosilicate-hydrate (N-A-S-H) gel backbone, promoted the geopolymerization process, led to moreQ4(3Al),Q4(2Al) and Q4(1Al) gel formation and a higher compressive strength of the geopolymers. This provided a basis for the preparation of CSRT-based geopolymers into marine concrete.Keywords:copper slag reprocessing tailings;geopolymer;microstructure;NMR
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2022
·
IF 5.204
Juxiang Chen,Ke Zhang,Kuiyuan Zhang,Bo Jiang,Yudong Huang
Phenolic resins with irreversible cross-links structure make them difficult to degrade and recycle. It is an emerging trend for phenolic resins thermoset to develop a rapid and facile closed-loop recycling approach. Herein, the degradable and reprocessable phenolic thermosets (PRTs) based on reversible acetal bonds were synthesized by tri(ethylene glycol) divinyl ether (TEGDVE) and linear phenolic resin through one-step “click” addition reaction. By employing the chain mobility induced by dynamic weak acetal motifs and linear TEGDVE in PRTs, the mechanical strengths could be rationally adjusted, and more moderate reprocessing and degradation conditions were achieved. Accordingly, the flexible structure units containing weak reversible acetal linkages were expected to accelerate the mobility of the chain segments and decrease the reprocessing temperature, while the linear phenolic structure afforded the high mechanical strength. Remarkedly, a champion degradation rate of 121.8 mg·mL −1 ·h −1 was achieved under acid condition by adjusting the ratio of flexible chains consisting of dynamic acetal bonds. In addition, compared with pristine PRTs, regenerative one maintained 93.41% of elongation at break. This work may shed a light for realizing degradable and reprocessable dynamic network materials with high efficiency.
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
ACS Sustainable Chemistry & Engineering
·
2025
·
IF 7.3
Shiqiang Liu,Bin Wang,Shihang Jin,Lin Zhang,Zhizhou Yang,Yue Wu,Sheng Gao
Silicone resins, known for their exceptional properties across various industries, are traditionally nonreprocessable due to their permanent cross-linked networks. Herein, we propose a method to turn a disadvantage into an advantage by converting silanol (Si–OH) groups─adverse factors for thermal stability─into dynamic Si–O–Ph bonds, thereby endowing silicone resin with reprocessability. Polysiloxane oligomers with benzoxazine side groups (PBTS) were formed via hydrolysis–condensation reactions between monofunctional benzoxazine-containing siloxane (P-mdes) monomers and triethoxymethylsilane (MTES). The curing behaviors of PBTS are analyzed using DSC and FTIR, confirming the formation of silicone resin-based covalent adaptive networks (CANs) through the introduction of dynamic Si–O–Ph bonds. The resulting silicone resin-based CANs exhibit reprocessability and significantly improved mechanical and thermal properties. The tensile strength of the original silicone resin-based CANs reaches 23.34 MPa, and even after five cycles of reprocessing, the strength remains at 22.98 MPa, demonstrating excellent mechanical retention. The Tg and Td5 of the silicone resin-based CANs reach up to 132 °C, 424 °C, and 425 °C in nitrogen or air atmospheres, respectively. Notably, the reprocessed samples maintain excellent heat resistance and thermal stability even after five reprocessing cycles, with Tg and Td5 values around 130 and 380 °C.
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）