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Bioactive materials 2023年第3期21卷 20-31页

作者： Tengling Wu Xiaoping Zhang Yang Liu Chunyan Cui Yage Sun Wenguang Liu School of materials Science and Engineering Tianjin Key Laboratory of Composite and Functional MaterialsTianjin UniversityTianjin300350China

Hydrogel patch-based stem cell transplantation and microenvironment-regulating drug delivery strategy is promising for the treatment of myocardial infarction(MI).However,the low retention of cells and drugs limits their therapeutic efficacies.Here,we propose a prefixed sponge carpet strategy,that is,aldehyde-dextran sponge(ODS)loading anti-oxidative/autophagy-regulating molecular capsules of 2-hydroxy-β-cyclodextrin@resveratrol(HP-β-CD@Res)is first bonded to the rat’s heart via capillary removal of interfacial water from the tissue surface,and the subsequent Schiff base reaction between the aldehyde groups on ODS and amino groups on myocardium tissue.Then,an aqueous biocompatible hydrazided hyaluronic acid(HHA)solution encapsulating mesenchymal stem cells(MSCs)is impregnated into the anchored carpet to form HHA@ODS@HP-β-CD@Res hydrogel in situ via click reaction,thus prolonging the in vivo retention time of therapeutic drug and cells.Importantly,the HHA added to outer surface consumes the remaining aldehydes to contribute to nonsticky top surface,avoiding adhesion to other tissues.The embedded HP-β-CD@Res molecular capsules with antioxidant and autophagy regulation bioactivities can considerably improve cardiac microenvironment,reduce cardiomyocyte apoptosis,and enhance the survival of transplanted MSCs,thereby promoting cardiac repair by facilitating angiogenesis and reducing cardiac fibrosis.

关键词： Myocardial infarction Sponge Hydrogel patch Wet adhesive Autophagy

Carbon-based materials with combined functions of thermal management and electromagnetic protection: Preparation, mechanisms, properties, and applications

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Nano Research 2024年第3期17卷 883-903页

作者： Junwei Yue Yiyu Feng Mengmeng Qin Wei Feng School of materials Science and Engineering and tianjin key laboratory of composite and functional materials Tianjin UniversityTianjin 300350China

The proliferation of high-power,highly informationized,and highly integrated electronic devices and weapons equipment has given rise to increasingly conspicuous issues about electromagnetic(EM)pollution and thermal accumulation.These issues,in turn,impose constraints on the performance of such equipment and jeopardize personnel safety.Carbon materials,owing to their diverse and modifiable structures,offer adjustable thermal and electric conductivity,rendering them highly promising for applications in fields such as thermal management and EM protection which have garnered extensive research and review.The pursuit of integrated device and equipment development has elevated the demand for multifunctional materials,prompting significant research into carbon-based composite materials that include both thermal management and EM protection functionalities.Notably,there are no relevant reviews on this topic at present.Consequently,this work consolidates research findings from recent years on carbon matrix composites exhibiting dual attributes of thermal management and EM protection.These attributes include thermally conductive electromagnetic interference(EMI)shielding materials,thermally insulating EMI shielding materials,thermally conductive EM wave(EMW)absorbing materials,and thermally insulating EMW absorbing materials.The paper elucidates the fundamental principles underpinning thermal conduction,thermal insulation,EMW absorbing,and EMI shielding.Additionally,it engages in discussions surrounding areas of contention,design strategies,and the functional properties of various material designs.Ultimately,the paper concludes by presenting the challenges encountered and potential research strategies about composites endowed with both thermal management and EM protection functionalities,while also envisaging the development of novel multifunctional EM protection materials.

关键词： carbon-based composites electromagnetic interference shielding microwave absorption thermal conduction thermal insulation

Enhanced Phase Transition in Poly(ethylene glycol) Grafted Butene-1 Copolymers

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Chinese Journal of Polymer Science 2023年第3期41卷 414-421,I0008页

作者： Ya-Hui Lou Wei Li Chun-Jing Qv Zhe Ma tianjin key laboratory of composite and functional materials and School of Materials Science and EngineeringTianjin UniversityTianjin 300072China

In the present work,a series of poly(ethylene glycol) grafted polybutene-1 copolymers(PB-g-PEG) were designed and successfully synthesized with reaction intermediate method,of which the branch densities and length could be tuned independently.The branch density varied from 0.39 mol% to 1.23 mol% and the branch length was tuned by employing PEG number-averaged molecular weight(Mn) from 350 Da to 750 Da and 1000 Da.The non-isothermal crystallization and phase transition behaviors of these butene-1 copolymers with varying branches were systematically explored by differential scanning calorimeter.The results first showed that compared with the linear polybutene-1 homopolymer,presence of steric 4-[4-(trimethylsilylalkynyl)-phenyl]-1-butene(TMS) groups suppressed crystallization and phase transition of copolymers.Interestingly,the introduction of long poly(ethylene glycol)(PEG) branches with M_(n)=350-1000 Da not only elevated the peak temperature of the non-isothermal crystallization but also enhanced the Ⅱ-Ⅰ phase transition,with respect to copolymers with TMS groups.Furthermore,the quantitative correlations between phase transition kinetics with the branch parameters(density and length) were explored.It was found that the phase transition presents a non-monotonic trend with increasing branch density and branch length.In this case,the optimal branch density and length obtained were 0.77 mol% and 750 Da,respectively.Employing the small angle X-ray scattering and transmission electron microscopy,a direct correlation between the phase transition kinetics and the long periodicity of separated phase was obtained,which may be due to the increased internal stress and facilitated stress transport.

关键词： Polybutene-1 copolymer Crystallization kinetics Phase transition Phase separation

Self-nucleation Effect of Crystallization with Various Nucleating Agents

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Chinese Journal of Polymer Science 2023年第12期41卷 1912-1920,I0009页

作者： Dai Zhang Rui-Jun Zhao Gui-Qiu Ma Zhe Ma tianjin key laboratory of composite and functional materials and School of Materials Science and EngineeringTianjin UniversityTianjin 300072China

In this work,the self-nucleation effect on crystallization was studied for polypropylene with various nucleating agents.The talc was employed to accelerate crystallization of monoclinic α-crystallites,while N,N′-dicyclohexyl-2,6-naphthalenedicarboxamide TMB-5 was used to accelerate the crystallization kinetics and also induce formation of trigonal β-crystallites.To induce self-nucleation effect,the occurrence criterion was assessed by the transition temperatures from various domains and the available temperature width.More importantly,the resulting influences of self-nucleation effect were quantified by the change of crystallization kinetics and the potential polymorphism variation.It was found that the α-nucleating agents of talc broadened the temperature window for inducing Domain Ⅱ by elevating the transition temperature from Domain Ⅰ to Domain Ⅱ.Although β-nucleating agent(β-NA)of N,N′-dicyclohexyl-2,6-naphthalenedicarboxamide TMB-5 elevated cooling crystallization temperature obviously,the temperature window for Domain Ⅱ was narrowed.It should be emphasized that in presence of β-NA TMB-5,the self-nucleation effect enhances the crystallization of α-crystallite,which show the competition with β-NA TMB-5.At last,the ternary PP/talc/TMB-5 blend was prepared with the same amounts of α-NA talc and β-NA TMB-5 and it exhibits a similar self-nucleation effect of crystallization,indicating the dominant role of β-NA TMB-5.

关键词： Crystallization Kinetic Polymorphism

The Influence of Various Cationic Group on Polynorbornene Based Anion Exchange Membranes with Hydrophobic Large Steric Hindrance Arylene Substituent

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Chinese Journal of Polymer Science 2023年第2期41卷 278-287页

作者： Wei Wang Da-Fu Cao Xiao-Wei Sun Li Pan Zhe Ma Yue-Sheng Li tianjin key laboratory of composite and functional materials School of Materials Science and EngineeringTianjin UniversityTianjin300350China

A series of brominated polynorbornene derivatives,including bulky steric hydrophobic groups and highly physical and chemical stable backbones,were synthesized via ring-opening metathesis polymerization and post-functionalized with trimethylammonium(QA),N-methylimidazole(Im),N-methylpyrrolidinium(Pyr)or N-methylpiperidinium(Pip)to construct the entire anion exchange membranes(AEMs).Benefited from prominent phase-separated morphology,PBO-x%-y(x=66,68,70;y=QA,Im,Pyr,Pip)AEMs with ion exchange capacity(IEC)approaching 2.0 meq·g^(−1)exhibited super high hydroxide conductivities.Thereinto,PBO-70%-Pip possessed the highest hydroxide conductivity of 137.3 mS·cm^(−1)at 80℃Moreover,all membranes exhibit low swelling ratio(SR)(the SR of PBO-66%-QA was just 8.6%at 80℃).That is,bulky steric hydrophobic groups play a crucial role in balancing the high hydroxide conductivity and low SR in AEMs.Furthermore,three AEMs(PBO-66%-QA,PBO-68%-Pyr,PBO-70%-Pip)showed good alkaline stability after immersion into 1.0 mol/L NaOH aqueous solution at 80℃for 480 h without any degradation.

关键词： Anion exchange membrane Steric hindrance Phase separation Ion conductivity Swelling ratio

3D打印强韧两性离子聚碳酸酯聚氨酯半月板替代物用于改善软骨磨损

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Science China materials 2023年第9期66卷 3744-3756页

作者：吴阳张倩杨徐轩张晓平聂雄峰肖萌姚远徐子扬刘文广 School of materials Science and Engineering Tianjin Key Laboratory of Composite and Functional MaterialsTianjin UniversityTianjin 300350China

开发同时满足韧性、抗疲劳性和润滑性等多种体内需求的半月板替代物仍面临巨大挑战.本文首先通过磺基甜菜碱二醇、聚碳酸酯二醇和六亚甲基二异氰酸酯之间的反应合成两性离子聚氨酯的预聚物,并通过己二酸二酰肼对两性离子聚氨酯预聚物进... 详细信息

开发同时满足韧性、抗疲劳性和润滑性等多种体内需求的半月板替代物仍面临巨大挑战.本文首先通过磺基甜菜碱二醇、聚碳酸酯二醇和六亚甲基二异氰酸酯之间的反应合成两性离子聚氨酯的预聚物,并通过己二酸二酰肼对两性离子聚氨酯预聚物进行扩链,制得多重氢键交联的两性离子超分子聚氨酯.通过调节硬段中的氢键和水环境下的水合作用,引入的两性离子侧基可以显著提高聚氨酯弹性体的韧性、可打印性和润滑性.通过熔融沉积成型3D打印技术可以在无需任何后处理的前提下,定制兼具强韧性和润滑性的两性离子聚氨酯半月板支架.在溶胀平衡状态下, 3D打印的两性离子聚氨酯结构的杨氏模量为16.87±2.00 MPa,韧性为19.90±5.94 MJ m^(-3),撕裂能为12.51±1.57 kJ m^(-2),且耐疲劳性优异.将3D打印两性离子聚氨酯半月板替代物植入兔膝关节12周,体内结果表明其能够有效减轻软骨表面磨损的问题.

关键词：己二酸二酰肼聚碳酸酯二醇聚氨酯弹性体耐疲劳性水合作用两性离子 3D打印聚碳酸酯聚氨酯

Potassium Acetate/18-Crown-6 Pair:Robust and Versatile Catalyst for Synthesis of Polyols from Ring-Opening Copolymerization of Epoxides and Cyclic Anhydrides

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Chinese Journal of Chemistry 2023年第1期41卷 83-92页

作者： Xiaoqing Dou Xiao-Hui Liu Bin Wang Yue-Sheng Li School of materials Science and Engineering Tiangong UniversityTianjin 300387China tianjin key Lab of composite&functional materials School of Materials Science and EngineeringTianjin UniversityTianjin 300350China

Efficient synthesis of polyester polyols with tunable molecular weight and microstructures from cyclic anhydride/epoxide mixtures by taking advantage of chain transfer reaction remains a great challenge,because most of the catalysts exhibit poor tolerance to chain transfer agent(CTA).In this contribution,we demonstrated that potassium acetate(KOAc)and 18-crown-6(18-C-6)combination has great potential in the synthesis of diverse polyester polyols with controllable molecular weight and high-end group ***-pared with KOAc,KOAc/18-C-6 pair could induce a much faster chain transfer between the active and dormant chains,and thus produce polyester polyols with narrow and monomodal distribution.In addition,polyester polyols could be efficiently prepared in laboratory by using commercially available cyclic anhydride without further purification(containing about 2%diacid residual as CTA)with an extremely low catalyst loading([catalyst pair]:[anhydride]:[epoxide]=1:50000:250000,[catalyst pair]=0.0004 mol%).KOAc/18-C-6 could also promote the self-switchable copolymerization of cyclic anhydride/epoxide/cyclic ester mixtures.Ring-opening copolymerization of cyclic ester was initiated automatically after the full conversion of cyclic anhydride,finally producing polyester polyols with ABA-type block structure.

关键词： Ring-opening polymerization Macrocyclic ligands Block copolymer Cyclic Anhydride Epoxide

A gel microparticle-based self-thickening strategy for 3D printing high-modulus hydrogels skeleton cushioned with PNAGA hydrogel mimicking anisotropic mechanics of meniscus

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Bioactive materials 2023年第8期26卷 64-76页

作者： Ziyang Xu Qian Zhang Chuanchuan Fan Meng Xiao Rong Yang Yuan Yao Yang Wu Xiongfeng Nie Hongying Wang Wenguang Liu School of Material Science and Engineering Tianjin Key Laboratory of Composite and Functional MaterialsTianjin UniversityTianjin300350China

Developing a meniscus substitute mimicking the anisotropic mechanics(higher circumferential tensile modulus and lower compressive modulus)of native tissue remains a great challenge.In this work,based on the pendant group structure-dependent H-bonding strengthening mechanism,two kinds of amide-based H-bonding crosslinked hydrogels with distinct mechanical behaviors,that is,the flexible poly(N-acryloyl glycinamide)(PNAGA)and the ultra-stiff poly(N-acryloylsemicarbazide)(PNASC)hydrogels are employed to construct the biomimetic meniscus substitute.To this end,a gel microparticle-based self-thickening strategy is first proposed to fabricate PNASC(GMP-PNASC)high-modulus hydrogels skeleton by extrusion printing technology in mimicking the collagen fibers in native meniscus to resist the circumferential tensile stress.Then,the PNAGA hydrogel is infused into the PNASC skeleton to replicate the proteoglycan,providing a lower compressive modulus.By regulating the structural features at the interior and peripheral regions,the GMP-PNASC/PNAGA hydrogel meniscus scaffold with the higher tensile modulus(87.28±6.06 MPa)and lower compressive modulus(2.11±0.28 MPa)can be constructed.In vivo outcome at 12 weeks post-implantation of rabbit’s medial meniscectomy model confirms the effects of GMP-PNASC/PNAGA meniscus scaffold on alleviating the wear of articular cartilage and ameliorating the development of osteoarthritis(OA).

关键词： Extrusion printing Gel microparticle High-modulus hydrogel Meniscus substitute

An Azo-PDMS-based wearable UV sensor with the optimized photo response mode for dual sensing and synchronous detection

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Science China(Technological Sciences) 2022年第1期65卷 179-190页

作者： QI YuHao ZHENG JunPing tianjin key laboratory of composite and functional materials School of Materials Science and EngineeringTianjin UniversityTianjin 300350China

A wearable UV sensor is designed to realize UV detection and a warning effect on people’s excessive UV exposure.It is noteworthy that the photoelectric system and supporting material of the most conventional sensor are separated.The unstable connection between the two components and the complicated construction method makes the sensor susceptible to external motion interference and prone to failure.Herein,we developed a unique photo response mode of the UV sensor based on a novel photo responsive material.An azobenzene-containing polydimethylsiloxane(Azo-PDMS)film was prepared as the outer layer of the sensor.It integrated the functions of photo response source,support and protection,which realized the direct contact and rapid response to the UV light source.Carbon nanotube(CNT),wrapped in the middle of Azo-PDMS films as an inner layer,transformed the photomechanical response signal into the photoelectric signal.The photo response mode endows the sensor with excellent anti-motion interference capabilities and a true sense of UV-strain synchronous monitoring performance,which is of great significance to the practical application of wearable devices.In addition,based on the excellent properties of Azo-PDMS,the sensor can also protect the human body from UV damage,self-repair after fracture,and realize personalized customization through 3 D printing.It makes a breakthrough in the design and construction of wearable UV sensors and paves a new way to optimize sensor photo response modes.

关键词： azobenzene polydimethylsiloxane wearable UV sensor synchronous detection

Memory Effect of Crystallization in 1-Butene/α-olefin Copolymers

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Chinese Journal of Polymer Science 2022年第6期40卷 576-583页

作者： Chun-Jing Qv Wei Li Rui-Jun Zhao Zhe Ma tianjin key laboratory of composite and functional materials and School of Materials Science and EngineeringTianjin UniversityTianjin 300072China

The macromolecular architecture is the crucial factor in determining the arrangement of the ordering structures,which,because of the multiscale feature,may exhibit distinct melting behaviors and induce the so-called memory effect to affect the following recrystallization.Until present,the correlation between the occurrence of memory effect and the intrinsic molecular structure is still far from the comprehensive understanding.In this work,four kinds of 1-butene/α-olefin random copolymers were designed and synthesized using the(pyridyl-amino)hafnium catalyst to introduce the different branches.The branch length was precisely controlled by the specific α-olefin comonomers,which include 1-hexene,1-decene,1-tetradecene,and 1-octadecene,while the branch density was tuned by the incorporation.As expected,the incorporation of α-olefin co-units to poly(1-butene)backbone decreases the non-isothermal crystallization kinetics and the degree of crystallinity.More interestingly,the resulting linear branch can induce the occurrence of memory effect and the threshold concentration of co-units(i.e.,branch density)decreases with increasing the branch length.Based on the results of these 1-butene/α-olefin copolymers with designable branches,a direct correlation with the occurrence of memory effect and the fraction of amorphous region was established,which quantitatively indicates the degree of local segregation of the crystallized poly(1-butene)sequences by theα-olefin co-units.

关键词： Memory effect 1-Butene/α-olefin copolymer Linear branch Crystallinity