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Chinese Journal of Chemistry 2024年第9期42卷 963-972页

作者： Haoran Zhang JiaojiaoQin Xiaoyan Tang Beijing National Laboratoryfor Molecular Sciences Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCenterfor Soft Matter Science and EngineeringCollegeof Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

Poly(3-hydroxybutyrate),a crucial member of the large biodegradable polyhydroxyalkanoate family,suffers from its *** enhance its performance,we employed a straightforward approach involving the ring-opening copolymerization of racemic-β-butyrolactone(rac-β-BL)andβ-propiolactone(β-PL)using the syndio-selective amino-alkoxy-bis(phenolate)-yttrium complex as a catalyst,thanks to the excellent ductility of poly(3-hydroxypropionate).Control over the rac-β-BL/β-PL feeding ratios and polymerization time yielded random or block copolymers with tunable thermal and mechanical properties comparable to traditional fossil-based ***,we achieved one-pot synthesis of hard-soft-hard triblock copolymers by exploiting monomers’different copolymerization rates and a bifunctional initiator,thus transforming polyhydroxyalkanoates from hard and tough plastics to soft and ductile thermoplastic elastomers.

关键词： Ring-opening(co-)polymerization Biodegradable polymers Polyhydroxyalkanoates Copolymers Plastics elastomers

Long-Range Electronic Effect-Promoted Ring-Opening Polymerization of Thioctic Acid to Produce Biomimetic Ionic elastomers for Bioelectronics

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CCS Chemistry 2024年第3期6卷 761-773页

作者： Hongfei Huang Huijing Wang Lijie Sun Ruohan Zhang Luzhi Zhang ZekaiWu Yaxuan Zheng Yang Wang Wei Fu Youwei Zhang Rasoul Esmaeely Neisiany Zhengwei You State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringInstitute of Functional MaterialsDonghua UniversityResearch Base of Textile Materials for Flexible Electronics and Biomedical Applications(China Textile Engineering Society)Shanghai Engineering Research Center of Nano-Biomaterials and Regenerative MedicineShanghai 201620 Institute of Pediatric Translational Medicine Shanghai Children’s Medical CenterSchool of MedicineShanghai Jiao Tong UniversityShanghai 200127 Department of Materials and Polymer Engineering Faculty of EngineeringHakim Sabzevari UniversitySabzevar ***

Poly(disulfide)s have been widely used in flexible wearable electronics,smart materials,and drug *** synthesis of poly(disulfide)s usually utilizes external stimuli or toxic initiators to promote the ***,we indicated that the long-range electronic effect can significantly alter the reactivity of the disulfide ***,we established deprotonation-promoted ring-opening polymerization of thioctic acid(TA)as a highly effective and simple method to synthesize poly(disulfide)s due to the long-range electronic effect and nucleophilic *** external stimuli and initiators,simple mixing of TA and deprotonation reagent,choline bicarbonate,in different ratios at room temperature rapidly produced a series of high molecular weight(up to 772 kDa)ionic liquid crystal poly(disulfide)s elastomers with room temperature self-healing ability,adjustable conductivity(2.39×10^(−2)∼0.28×10^(−2)S m^(−1)),degradability,biocompatibility,antibacterial property,and tissue-like softness(Young’s moduli ranging from 18.2±6.0 to 111.1±36.7 kPa).The experiments and density functional theory calculations also revealed the principle of long-range electronic effect to establish a new synthetic strategy of poly(disulfide)s with superior properties favorable for bioelectronics.

关键词： self-healing elastomers thioctic acid ionic liquid bioelectronics

Stretchable poly[2]rotaxane elastomers

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Fundamental Research 2024年第2期4卷 300-306页

作者： Kai Liu Xinhai Zhang Dong Zhao Ruixue Bai Yongming Wang Xue Yang Jun Zhao Hao Zhang Wei Yu Xuzhou Yan School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative MoleculesShanghai Key Laboratory of Electrical Insulation and Thermal AgingShanghai Jiao Tong UniversityShanghai 200240China College of Chemistry and Chemical Engineering National Engineering Research Center for Dyeing and Finishing of TextilesDonghua UniversityShanghai 201620China

Mechanically interlocked polymers(MIPs)are promising candidates for the construction of elastomeric materials with desirable mechanical performance on account of their abilities to undergo inherent rotational and translational mechanical movements at the molecular ***,the investigations on their mechanical properties are lagging far behind their structural fabrication,especially for linear polyrotaxanes in ***,we report stretchable poly[2]rotaxane elastomers(PREs)which integrate numerous mechanical bonds in the polymeric backbone to boost macroscopic mechanical ***,we have synthesized a hydroxyfunctionalized[2]rotaxane that subsequently participates in the condensation polymerization with diisocyanate to form *** from the peculiar structural and dynamic characteristics of the poly[2]rotaxane,the representative PRE exhibits favorable mechanical performance in terms of stretchability(∼1200%),Young’s modulus(24.6 MPa),and toughness(49.5 MJ/m^(3)).Moreover,we present our poly[2]rotaxanes as model systems to understand the relationship between mechanical bonds and macroscopic mechanical *** is concluded that the mechanical properties of our PREs are mainly determined by the unique topological architectures which possess a consecutive energy dissipation pathway including the dissociation of host−guest interaction and consequential sliding motion of the wheel along the axle in the[2]rotaxane motif.

关键词： Polyrotaxanes Mechanically interlocked polymers Mechanically interlocked molecules Dynamic materials elastomers

Dispersion and Filler Network Structure of Fibrillar Silicates in elastomers

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Chinese Journal of Polymer Science 2016年第7期34卷 858-872页

作者： Zhao Li Hai-bin Sun Cong-yi Li Yong-lai Lu Wang Qiao 宁南英 Li-qun Zhang 田明 Aeolus Tyre Co. Ltd State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical Technology Petro China Sichuan Petrochemical Co. Ltd Office of Scientific Research and Development Beijing University of Chemical Technology

The dispersion and filler network of fibrillar silicate（FS） in elastomers were studied. The results showed that a good dispersion of FS in matrix during mechanical blending in unvulcanized composites contributed to a strong FS filler network, different from that of traditional reinforcing fillers. Meanwhile, the filler re-aggregation during vulcanization caused by the overlapping and intertwining of FS further strengthened the filler network. The factors including Mooney viscosity and molecular polarity of elastomer, type and amount of silane coupling agents used for filler modification, that may influence the filler network, were studied. Our study helps us to understand the mechanism for the formation of filler network of FS in elastomers and provides guidance for the preparation of high performance FS/elastomer composites.

关键词： Fibrillar silicates Dispersion Filler network elastomers

Super Strong and Tough elastomers Enabled by Sacrificial Segregated Network

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Chinese Journal of Polymer Science 2021年第3期39卷 377-386,I0008页

作者： Yong Zhu Lai-Yun Wei Xuan Fu Jun-Qi Zhang Ling-Min Kong Guang-Su Huang Jin-Rong Wi State Key Laboratory of Polymer Materials Engineering College of Polymer Science and EngineeringSichuan UniversityChengdu 610065China

The integration of high strength and toughness concurrently is a vital requirement for elastomers from the perspective of long-term durability and reliability. Unfortunately, these properties are generally conflicting in artificial materials. In the present work, we propose a facile strategy to simultaneously toughen and strengthen elastomers by constructing 3 D segregated filler network via a simple latex mixing *** as-fabricated elastomers are featured by a microscopic 3 D interconnected segregated network of rigid graphene oxide(GO) nanosheets and a continuous soft matrix of sulfur vulcanized natural rubber(NR). We demonstrate that the interconnected segregated filler network ruptures preferentially upon deformation, and thus is more efficient in energy dissipation than the dispersed filler network. Therefore, the segregated filler network exhibits better reinforcing effects for the rubber matrix. Moreover, the excellent energy dissipating ability also contributes to the outstanding crack growth resistance through the release of concentrated stress at the crack tip. As a result, the strength, toughness and fatigue resistance of the nanocomposites are concurrently enhanced. The methodology in this work is facile and universally applicable, which may provide new insights into the design of elastomers with both extraordinary static and dynamic mechanical performance for practical applications.

关键词： elastomers Nanocomposites Segregated network Sacrificial bonds Mechanical properties

Study on Preparation and Properties of Polyether Polytriazole elastomers

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Chinese Journal of Polymer Science 2015年第4期33卷 597-606页

作者：翟进贤 Zheng-yang Qu Ye-cheng Zou Xiao-yan Guo Rong-jie Yang School of Materials Beijing Institute of Technology

To explore the application of click chemistry in the field of elastomer materials, propargyl-terminated ethylene oxide-tetrahydrofuran copolymer （PTP（E-co-T）） was prepared from hydroxyl-terminated ethylene oxide-tetrahydrofuran copolymer （P（E-co-T）） by end-etherisation modification. FTIR and ^13C-NMR results indicate that P（E-co-T）-terminated hydroxyl was etherified thoroughly, yielding the target product PTP（E-co-T）, and the content of terminated alkynyl of PTP（E-co-T） was evaluated to be 0.428 mmol.g^-l. Using a polyazide compound as a cross-linker, polytriazole elastomers with various functional molar ratio （R） values were prepared from PTP（E-co-T） by virtue of the CuAAC reaction. Mechanical property tests indicate that with the increase in R, the modulus E and stress Orb of the polytriazole elastomers first increase and subsequently decrease, whereas the strain first decreases and later increases. The mechanical properties of the polytriazole elastomers show a parabolic dependence on the R value. Near the stoichiometric ratio, E and Orb show maxima and the strain εb shows a minimum. Swelling tests demonstrate that the apparent molecular weight of polytriazole elastomer strands also first decreases and subsequently increases. At the stoichiometric ratio, the network structure possesses strands with a minimum apparent molecular weight and a maximum apparent density. Dynamic mechanical analysis reveals that the polytriazole elastomers presented damping peaks at approximately -64℃, corresponding to the glass transition of copolyether strands, and the elastomer exhibited the lowest dissipation factor tanδ at the stoichiometric ratio. Thermal analysis suggests that the weight-loss process of the polytriazole elastomer is characteristic of one-step decomposition, and the elastomer begins to decompose from polyether strands, not triazole groups.

关键词： Click chemistry Polytriazole elastomers PTP(E-co-T).

Peptidoglycan-inspired autonomous ultrafast self-healing bio-friendly elastomers for bio-integrated electronics

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National Science Review 2021年第5期8卷 130-139页

作者： Luzhi Zhang Jiahui Liang Chenyu Jiang Zenghe Liu Lijie Sun Shuo Chen Huixia Xuan Dong Lei Qingbao Guan Xiaofeng Ye Zhengwei You State Key Laboratory for Modification of Chemical Fibers and Polymer Materials Shanghai Belt and Road Joint Laboratory of Advanced Fiber and Low-dimension MaterialsCollege of Materials Science and EngineeringDonghua University Department of Cardiac Surgery Ruijin HospitalShanghai Jiao Tong University School of Medicine

elastomers are essential for stretchable electronics, which have become more and more important in bio-integrated devices. To ensure high compliance with the application environment, elastomers are expected to resist, and even self-repair, mechanical damage, while being friendly to the human ***, inspired by peptidoglycan, we designed the first room-temperature autonomous self-healing biodegradable and biocompatible elastomers, poly(sebacoyl 1,6-hexamethylenedicarbamate diglyceride)(PSe HCD) elastomers. The unique structure including alternating ester-urethane moieties and bionic hybrid crosslinking endowed PSeHCD elastomers superior properties including ultrafast self-healing,tunable biomimetic mechanical properties, facile reprocessability, as well as good biocompatibility and biodegradability. The potential of the PSeHCD elastomers was demonstrated as a super-fast self-healing stretchable conductor(21 s) and motion sensor(2 min). This work provides a new design and synthetic principle of elastomers for applications in bio-integrated electronics.

关键词： biomimetic elastomers ultrafast self-healing bio-integrated electronics stretchable conductor

Damping of magnetorheological elastomers

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Journal of Central South University 2008年第S1期15卷 271-274页

作者：陈琳龚兴龙 CAS Key Laboratory of Mechanical Behavior and Design of Materials University of Science and Technology of China Department of Modern Mechanics University of Science and Technology of China

The damping property of magnetorheological elastomers(MREs) is characterized by a modified dynamic mechanical-magnetic coupled *** influence of external magnetic flux density,damping of matrix,content of iron particles,dynamic strain and driving frequency on the MREs' damping was investigated *** results indicate that the MREs' damping property depends on the interfacial slip between the inner particles and the *** from the general composite materials,the interfacial slip in MRE is affected by the external applied magnetic field.

关键词： magnetorheological elastomers damping property interfacial slip

Electromechanical Properties of Ethylene Propylene Diene elastomers: Effect of Ethylene Norbornene Content

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Materials Sciences and Applications 2011年第5期2卷 307-313页

作者： Patcharee Intanoo Anuvat Sirivat Ruksapong Kunanuruksapong Wanchai Lerdwijitjarud 不详

Ethylene propylene diene elastomers (EPDM) of various side chains and molecular weights were prepared as thin discs and the effects of electric field strength and temperature on the electromechanical properties were investigated. The electrical conductivity, the dielectric constant, the storage and loss moduli (G' and G'), the storage modulus response (ΔG’1000 V/mm), and the storage modulus sensitivity (ΔG’1000 V/mm/G’0) of the elastomers of different ethylene norbornene (ENB) contents and molecular weights were measured under electric field strengths varying from 0 V/mm to 1000 V/mm and at temperatures between 300 K and 380 K. The storage modulus response and sensitivity increase with increasing molecular weight and dielectric constant, consistent with the existing theory. However, for the case of EPDMs with different ENB contents, the storage modulus response and sensitivity vary inversely with the dielectric constant. EDPM is potentially a new type of electroactive materials.

关键词： Dielectric Elastomer Dipole Moment Polar Molecule Unsaturated Structure Ethylene Propylene Diene elastomers (EPDM) Electrorheological Properties

Friction and Deformation Behavior of elastomers

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Materials Sciences and Applications 2019年第8期10卷 527-542页

作者： Alexander Adam Dominik Paulkowski Bernd Mayer Fraunhofer Institute for Manufacturing Technology and Advanced Materials Bremen Germany Faculty of Production Engineering University of Bremen Bremen Germany

This research paper is about investigating the mechanisms of elastomeric friction at low velocities. To do so, different experimental setups were performed to analyze friction, adhesion and surface energy among others. The tested materials were EPDM samples with variations in the carbon black content. It was found, that at least for low velocities, the real contact area has the main impact on the friction of elastomers. This contact area seems to be highly influenced by the hardness or other bulk properties of the elastomers, which are modified by the varying carbon black content.

关键词： elastomers Friction Adhesion Tribology Carbon Black Variation Contact Area