MACROMOLECULES
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2021
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IF 5.985
Yang You,Min Zhi Rong,Ming Qiu Zhang
The present work proposes a novel strategy to prepare reversibly interlocked networks with enhanced mechanical properties through hierarchy-induced multilevel energy consumption mechanisms. The core issue lies in the introduction of in situ inter-macromolecular ionic interactions among the component networks regardless of their miscibility, which is hard to be implemented in other materials. Traditional small-molecule contra-ions are no longer necessary accordingly. As revealed by the proof-of-concept transparent interlocked networks composed of immiscible cross-linked styrene–butadiene rubber (SBR) and polyethylenimine (PEI), the interlocking architecture and the inter-macromolecular ionic interactions are mutually promoted. The latter pulls the immiscible polymer chains together, favoring the formation of the former, while the former prevents the neighboring chains from separation and helps the complexation among the counterpart functional groups. Eventually, multilevel energy consumption mechanisms can be triggered under the applied force and the conventionally conflicting properties including strength, toughness, and creep resistance of the interlocked networks are remarkably increased at the same time. Moreover, the moisture sensitivity that used to accompany ionic interactions disappears, which broadens the application scope of the materials in practice. Owing to the included reversible Diels–Alder bonds and Schiff base, the SBR and PEI-based interlocked networks are self-healable and reprocessable and can even be unlocked producing the original single networks. It is anticipated that a versatile and facile platform technique may thus be developed for creating new polymeric materials with advanced multifunctionality.
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高影响因子
JOURNAL OF POLYMER RESEARCH
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2021
·Vol. 28
·期 6
·1-11
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IF 3.097
Wang Wei-Yu,Zha Xiang-Jun,Bao Rui-Ying,Ke Kai,Liu Zheng-Ying,Yang Ming-Bo,Yang Wei
Dynamics of exchange within vitrimer networks are influenced by mobility of the chemical species involved in the exchange reaction, then it can be affected by the crystalline phase when boronic ester bond is introduced into the thermoplastic elastomers with crystalline phase as physical cross-links. In this work, the dynamic dioxaborolane cross-links were introduced into commercial poly(ethylene-α-octene) (POE) with crystalline phases as physical cross-links to prepare POE vitrimers. The results of stress relaxation show that relaxation time (τ) follows an Arrhenius law with the temperature at the melting range for not only POE vitrimers and thermally treated POE vitrimers with dynamic cross-links, but also neat POE with purely physical cross-links. The liquid-to-solid transition temperature can raise to 35.3 °C for POE vitrimers from -42.9 °C of the thermally treated one, due to the constrained mobility by residual crystalline phases. The resulted POE vitrimers maintain a stress at break of higher than 27.5 MPa and an elongation at break of higher than 800% at room temperature. With the temperature increasing, the crystal melting induced weakening of the physical cross-linking in POE decreases the strength, but the storage modulus and the stress at 300% and 500% elongation of POE vitrimers are improved. The properties of POE vitrimers can almost keep unchanged after recycling or healing. All these results show that the introduction of reversible boronic ester bonds is a promising strategy to improve the performances and recyclability of physically cross-linked POE materials.
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高影响因子
Polymers
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2021
·Vol. 13
·期 11
·1679
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IF 4.329
Yanning Zeng,Weiming Yang,Shuxin Liu,Xiahui Shi,Aoqian Xi,Faai Zhang
Thermoset polymers show favorable material properties, while bringing about environmental pollution due to non-reprocessing and unrecyclable. Diels–Alder (DA) chemistry or reversible exchange boronic ester bonds have been employed to fabricate recycled polymers with covalent adaptable networks (CANs). Herein, a novel type of CANs with multiple dynamic linkers (DA chemistry and boronic ester bonds) was firstly constructed based on a linear copolymer of styrene and furfuryl methacrylate and boronic ester crosslinker. Thermoplastic polyurethane is introduced into the CANs to give a semi Interpenetrating Polymer Networks (semi IPNs) to enhance the properties of the CANs. We describe the synthesis and dynamic properties of semi IPNs. Because of the DA reaction and transesterification of boronic ester bonds, the topologies of semi IPNs can be altered, contributing to the reprocessing, self-healing, welding, and shape memory behaviors of the produced polymer. Through a microinjection technique, the cut samples of the semi IPNs can be reshaped and mechanical properties of the recycled samples can be well-restored after being remolded at 190 °C for 5 min.Keywords:CANs;semi IPNs;self-healing
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PubMed
高影响因子
POLYMER
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2020
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IF 4.231
Changhong Lin,Huan Ge,Tianle Wang,Min Huang,Puyou Ying,Ping Zhang,Jianbo Wu,Shibin Ren,Vladimir Levchenko
The realization of recyclable materials is an urgent problem to be solved for extending practical applications in industry. Herein, a simple method was proposed to prepared the recyclable materials thorough dynamic reversible chemistry . In this work, we design the recyclable and self-healing polyurethane based on the thermoreversible dynamic Diels-Alder reaction. In addition, the Halloysite nanotubes (HNTs) were introduced into the system to improve the thermal properties, mechanical properties of polyurethane nanocomposites (PUDM/HNTs). The tensile tests showed that the HNTs can significantly improved the mechanical properties of nanocomposites. The healing efficiency above 90% on average was achieved which was determined by the recovery of breaking strength . Besides, the composites exhibited outstanding reprocessability via thermally induced. Therefore, Such excellent recyclable performance and self-healing ability give the polyurethane materials an opportunity to have great potential in the fields of save-energy, friendly-environment materials.
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高影响因子
EUROPEAN FOOD RESEARCH AND TECHNOLOGY
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2020
·Vol. 246
·期 10
·2065-2077
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IF 2.366
Batool Zahra,Li Lin,Xu Dan,Wu Ming,Weng Longmei,Jiao Wenjuan,Cheng Hao,Roobab Umme,Zhang Xia,Li Xiaoxi,Liang Yi,Li Bing
Furan, which has been identified as possibly carcinogenic for humans, can be induced to different food items by thermal treatment. In accordance with the previous studies and risks associated with prevalence of furan in food, it is necessary to be acknowledged of amounts of furan formed in different thermally processed foods for human awareness. In this study, Headspace Solid-Phase Microextraction Gas Chromatography–Mass Spectrometry (HS-SPME-GC/MS) was optimized for simultaneous determination of furan, furfural, 2-methylfuran and 2-pentylfuran for the first time from different dried fruits and roasted nuts. The method was proved to be valid for determination of all analytes at 50 °C for 25 min, stirring at 700 rpm and 20% NaCl (W/V) using 50/30 μm divinlybenzene/carboxen/polysimethylsiloxane (DVB/CAR/PDMS) fibre. All analytes were baseline-separated at HP 5-MS column in less than 13 min and obtained results have shown prevalence of furan, furfural and 2-pentylfuran in the studied matrices; however, 2-pentylfuran was more prevalent in the roasted nuts than dried fruits and 2-methylfuran has not shown considerable prevalence in both matrices. Moreover, this method was validated in terms of linearity, precision, recovery, specificity, limit of detection and limit of quantification depending on analytes and sample matrices. Hence, the present method was proved to be highly sensitive, specific and robust with good precision and accuracy and suitable for monitoring these furan derivatives in the studied matrices.
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高影响因子
GREEN CHEMISTRY
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2020
·Vol. 22
·期 3
·850-859
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IF 9.48
Yang Qian,Ze-Jun Li,Xian-Long Du,Qi Zhang,Yi Zhao,Yong-Mei Liu,Yong Cao
Development of a highly efficient and robust catalyst with reduced usage of noble metals is extremely desirable for selective hydrogenations of furan-containing bio-based feedstocks, which represents an attractive and sustainable alternative to petrochemical resources. Herein, we describe a new type of well-dispersed Ru subnanoclusters (ca. 0.50 wt%) supported on commercial P25 TiO2 material obtained from a facile and effective amino acid-assisted deposition–precipitation strategy. The as-synthesized catalyst exhibits superior catalytic activity and selectivity for direct hydrogenation of industrially important furfural as well as a range of structurally diverse bio-based furanic compounds to their corresponding fully hydrogenated derivatives. An average turnover frequency (ATOF) value as high as 367 h−1 at 80 °C and 4 MPa H2 is obtained, which is the highest reported value. This catalyst also shows stable furfural total hydrogenation in 5 reaction cycles conducted at 80 °C (52 mmol-scale, turnover number up to 12 500). In terms of the kinetic and structural characterizations, the key performances of the ultrasmall Ru clusters are proposed to mainly originate from an enhanced number of unsaturated surface Ru atoms and change in local coordination environment. Our work highlights the importance of the subnanometric size of Ru clusters in the advancement of efficient and affordable approaches towards bio-based chemical production.
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高影响因子
POLYMER
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2019
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IF 3.771
Changhong Lin,Dekun Sheng,Xiangdong Liu,Shaobin Xu,Fance Ji,Li Dong,Yan Zhou,Yuming Yang
Graphene and modified Graphene often can be used as effective reinforcer or cross-linker in self-healing materials. However, the influence of fillers sheets size on the self-healing materials remained unclear. In this report, we investigate the effect of different graphene oxide (GO) sheets size in the properties of self-healing Polyurethane . The different sizes of graphene oxide (GO) were prepared from various sizes of graphite via the improved Hummers' method. Furthermore, the corresponding maleimide functionalized GO (mGO) sheets were synthesized from maleimide modification processing. The X-Ray photoelectron spectroscopy (XPS) analysis shows that the smaller size GO, the higher oxidation and functionalization. We systematically investigated the influence of size GO and mGO on the mechanical and self-healing performance of Polyurethane/Graphene Oxide (PG) and Polyurethane/maleimide modified Graphene Oxide (PM) with the dynamic thermal reversible Diels-Alder bonds. The results show that GO sheets in smaller size produce an advantage on the mechanical and self-healing behavior. Moreover, the PM nanocomposites exhibited superior mechanical and self-healing properties compared to PG nanocomposites at the same loading.
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高影响因子
PROGRESS IN ORGANIC COATINGS
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2019
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IF 3.42
Yechang Feng,Limin Man,Yang Hu,Lu Chen,Bingqing Xie,Chaoqun Zhang,Teng Yuan,Zhuohong Yang
Herein, castor and tung oil-based polyurethane-imides with tailored thermal and mechanical performance were developed by a one-pot method. First, tung oil (TO) was transformed into eleostearic acid diethanol amide (EADEA) by methyl-esterification and amidation. The resulting EADEA was then mixed with castor oil (CO), N -(2-hydroxyethyl)-maleimide (HEMI) and isophorone diisocyanate to prepare biobased polyurethane-imides. The formation of Diels-Alder (DA) adducts from EADEA and HEMI during the curing process was determined by proton nuclear magnetic resonance ( 1 H NMR) and Fourier transform infrared spectroscopy (FTIR). The effect of DA adducts contents on the thermal and mechanical properties of corresponding polymers was investigated. The results show that the introduction of TO-maleimide DA adducts significantly increases the glass transition temperature, tensile strength, Young’s modulus and gel content of the resulting polyurethanes. The highest tensile strength of the resulting polymers can reach 48.2 MPa. Besides, the thermal stability was also improved with the incorporation of imide groups. This technique reported here demonstrates several advantages, such as one-pot synthesis, high bio-renewable content, low cost and tunable performance, and it is promising to find application in coatings, adhesives and so on.
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高影响因子
CHEMICAL PHYSICS LETTERS
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2019
·
IF 1.901
Jianqiang Zhu,Narcisse T. Tsona,Abdelwahid Mellouki,Lin Du
The reactions of two selected ethers, methyl n-butyl ether (MnBE) and methyl s-butyl ether (MsBE), with three atmospheric oxidants (OH/NO 3 /Cl) have been investigated at 298 ± 2 K using the relative rate method and gas chromatography-mass spectrometry. The reaction trends of these short chain aliphatic ethers with the different oxidants have been discussed. From the obtained results, the reaction with OH is the main tropospheric loss process for MnBE and MsBE, with lifetimes of 19.2 h and 26.8 h, respectively. These short lifetimes indicate that the chemistry of these aliphatic ethers is important in areas close to their emission sources.
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高影响因子
Materials Today
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2019
·
IF 24.372
Yang You,Wei Li Peng,Pu Xie,Min Zhi Rong,Ming Qiu Zhang,Dong Liu
The combination of polymers can produce a multicomponent polymeric system, with advanced performance that cannot be achieved by the individual components. An ideal case lies in the creation of all interface materials to maximize the synergistic hybrid effects. Thus far, however, even for the elaborate interpenetrating polymer networks , microheterogeneity is inevitably observed. Herein, we show a conceptual innovative approach to prepare molecular-level interlocking polymer networks by topological reorganization of two immiscible single polymer networks with orthogonal reversible covalent crosslinkages. The conventional phase separation is suppressed as gelation proceeds, and the interlocked networks are further unlocked to a homogenous structure, recovering the original single polymer networks. The resultant interlocking polymer networks show nonlinear improvement in mechanical performance in addition to smart adaptivity like self-healability. An extensible platform technology for bringing in new materials may thus be developed, which is breakthrough in the scope of classic polymer engineering dominated by irreversible covalent chemistry . Furthermore, the long-range interlocked networks themselves are a promising model system for studying soft condensed matter physics .
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高影响因子
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
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2018
·
IF 4.841
Zhongwei Wang,Hu Li,Wenfeng Zhao,Song Yang
A novel carbon-increasing catalytic route via one-pot cascade acylation–alkylation of biomass-derived 2-methylfuran and acetic anhydride over Sn 4+ -exchanged K-10 montmorillonite (Sn 4+ -K-10) was demonstrated to be highly efficient for the production of C 17 oxygenate 1,1,1-tris(5-methyl-2-furyl)ethane with a high yield of 87% and 90% selectivity at 60 °C in 8 h under solvent-free conditions. Characterization techniques manifested Sn 4+ -K-10 to have layered and mesoporous (5.7 nm) texture structure, Lewis–Brønsted acid paired sites and uniformly dispersed Sn species, which greatly contributed to the predominant reactivity and recyclability of Sn 4+ -K-10. Systematic studies based on GC–MS and NMR were also conducted to elucidate the catalytic mechanism.
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高影响因子
FUEL PROCESSING TECHNOLOGY
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2018
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IF 3.956
Shanshan Shao,Huiyan Zhang,Rui Xiao,Xiaohua Li,Yixi Cai
To understand the evolution of coke in the catalytic conversion of biomass-derivates, in - situ diffuse reflectance Fourier transform infrared spectroscopy experiments and ex - situ extraction method were combined to identify the coke species. Considering the ring-shape and unsaturation of furan as an important intermediate from biomass pyrolysis , other simplified biomass-derivates like tetrahydrofuran , butanol , ethylene glycol and methanol was also studied to investigate the effect of its chemical structure on coke formation. The ex - situ study showed that the performance in the induction period and deactivation stage was closely related to the functional group of biomass-derivates. Coke extraction of furan and tetrahydrofuran were of similar composition , which was of doubt. Combined results with in - situ diffuse reflectance Fourier transform infrared spectroscopy revealed that polymethyl benzaldehyde was the main composition of active coke in the catalytic conversion of furan, and then intermediate of benzofuran was detected, and finally alkyl naphthalene and polyaromatic hydrocarbons were formed by polymerization and hydrogen transfer . This study will provide guidelines to enhance hydrocarbon production from the viewpoint of active coke like pre-feeding of polymethyl benzaldehyde.
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高影响因子
危险品化学品经营许可证（带存储）