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Theoretical Interpretation of Conformation Variations of Polydimethylsiloxane Induced by nanoparticles

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Chinese Journal of Polymer Science 2018年第4期36卷 505-513页

作者： Zhao-Yang Wei nan-ying ning Ming Tian Li-Qun Zhang Jian-Guo Mi State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical Technology Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical Technology

There has been controversy as to whether the addition of nanoparticles to a polymer melt causes perturbed chain structure of polymers. In this work, the chain conformations of polydimethylsiloxane（PDMS） with addition of polyhedral oligomeric silsesquioxane（POSS） nanoparticles have been studied using a classical density functional approach. Under the strong interactions of POSS-PDMS, the radius of gyration of PDMS in the nanocomposites can either increase or decline depending on particle loading. After adding nanoparticles with larger size or weaker interactions, both the increasing and the declining amplitudes can be largely suppressed. The results provide a deep understanding of chain conformation in polymer nanocomposites.

关键词： Chain conformation Radius of gyration Polymer nanocomposites Density functional theory

Silicone Elastomer with High Elongation at Break Used in Digital Light Processing 3D Printing

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Chinese Journal of Polymer Science 2023年第11期41卷 1786-1795,I0010页

作者： Tian-Xin Yu Ya-Yuan Liu Fu-Yue Tian nan-ying ning Bing Yu Ming Tian State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China Key Laboratory of Carbon Fiber and Functional Polymers Ministry of EducationBeijing University of Chemical TechnologyBeijing 100029China

3D printing silicone elastomer has demonstrated great potential in diverse areas such as medical devices,flexible electronics and soft *** is of great value to investigate how to improve the mechanical properties,including tensile strength and elongation at break of printed *** this work,a light curing system that can be applied in silicone elastomer 3D printing is explored,which is composed of vinyl terminated polysiloxane as the macromer and thiol containing polysiloxane as the crosslinking agent,and a chain extension reaction is also introduced into this light curing system via the addition of the chain extender dithiol molecules,and a light curing system accompanied with chain extension is designed and realized based on the thiol-ene click reaction *** reinforced with silica fillers,the obtained light curing system can endow the light curing silicone elastomer with better mechanical properties under the condition of a lower viscosity of the precursor,the tensile strength and elongation at break can reach 525.5 k Pa and 601%,*** light curing system provides a feasible method to solve the contradiction between the viscosity of the precursor and the mechanical properties of the light curing elastomer in the digital light processing(DLP)3D printing field.

关键词： Silicone elastomer Thiol-ene click chemistry Light curing 3D-printing Chain extender

Excellent Compatibilization Effect of a Dual Reactive Compatibilizer on the Immiscible MVQ/PP Blends

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Chinese Journal of Polymer Science 2023年第7期41卷 1133-1141页

作者： Han-Bin Wang Hong-Chi Tian Shi-Jia Zhang Bing Yu nan-ying ning Ming Tian Li-Qun Zhang Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials Beijing University of Chemical TechnologyBeijing100029China Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical TechnologyBeijing100029China Shandong Dawn Polymer Material Co. Ltd.Longkou265700China

Methyl vinyl silicone rubber (MVQ)/polypropylene (PP) thermoplastic vulcanizate (TPV) combines the good melt processability, recyclability and sealing performance as well as biosafety, stain and fluid resistance, and thus it is especially suitable in bio-safety areas and wearable electronic devices, etc. Nevertheless, the compatibility between MVQ and PP phases is poor. A big challenge on the compatibilization of MVQ/PP blends is that neither MVQ nor PP contains any reactive groups. In this study, a dual reactive compatibilizer composed of ethylenemethyl acrylate-glycidyl methacrylate terpolymer (EMA-co-GMA) and maleic anhydride grafted polypropylene (PP-g-MAH) was designed for the compatibilization of MVQ/PP blends. During melt blending, a copolymer compatibilizer at the MVQ/PP interface can be formed because of the in situ reaction between EMA-co-GMA and PP-g-MAH. The thermodynamic predict of its compatibilization effect through calculating the spreading coefficient of the in situ formed copolymer indicates that it can well compatibilize MVQ/PP blends. The experimental results show that under the GMA/MAH molar ratio of 0.5/1, the interface thickness largely increase from 102 nm for non-compatibilized blend to 406 nm, and the average size of MVQ dispersed phase largely decreases from 2.3 µm to 0.36 µm, the Tg of the two phases shifts toward each other, the mixing torque and mechanical properties of the blend are increased, all indicating its good compatibilization effect. This study provides a good compatibilizing method for immiscible MVQ/PP blends with no reactive groups in both components for the preparation of high performance MVQ/PP TPVs.

关键词： Methyl vinyl silicone rubber(MVQ) Polypropylene(PP) Immiscible polymer blends Reactive compatibilization

Polyurethane-polysiloxane Copolymer Compatibilized SiR/TPU TPV with Comfortable Human Touch Toward Wearable Devices

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Chinese Journal of Polymer Science 2023年第2期41卷 258-266页

作者： Hong-Fang Zhang Qian Hao Hong-Chi Tian Peng-Jun Yao Xue-ying Liu Bing Yu nan-ying ning Ming Tian Li-Qun Zhang Key Laboratory of Carbon Fiber and Functional Polymers Ministry of EducationBeijing University of Chemical TechnologyBeijing10029China Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical TechnologyBeijing100029China Shandong Dawn Polymer Material Co. Ltd.Longkou265700China Zhejiang Collaborative Innovation Center for High Value Utilization of Byproducts from Ethylene Project Ningbo PolytechnicNingbo315800China

Because of its softness,wear resistance,biocompatibility,extremely comfortable human touch,thermoplastic vulcanizate(TPV)comprised of silicone rubber(SiR)and thermoplastic polyurethane(TPU)(SiR/TPU TPV)is especially suitable for wearable intelligent ***,developing good compatibilizer is still required to prepare high performance SiR/TPU *** this study,three kinds of polyurethane-polysiloxane copolymer(PU-co-PSi)with different contents of polysiloxane segment were selected,and their compatibilization effect on SiR/TPU blends was studied using nanomechanical mapping technique of *** results show that using PU-co-PSi with the highest content of polysiloxane segment(PU-co-HPSi),the interface thickness largely increases,and the average size of SiR dispersed phase largely decreases,indicating its good compatibilization *** using PU-co-HPSi as compatibilizer,SiR/TPU TPV with a fine SiR dispersed phase and good mechanical performance were successfully *** mechanism on the compatibilization effect of these PU-co-PSi on SiR/TPU TPVs was revealed.

关键词： Silicone rubber(SiR) Thermoplastic polyurethane(TPU) Compatibilization Thermoplastic vulcanizate(TPV)

Morphologies and Mechanical Properties of Cis-1,4-butadiene Rubber/Polyethylene Blends

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Chinese Journal of Polymer Science 2016年第7期34卷 820-829页

作者： Hong Yao Jia-li Niu Jie Zhang nan-ying ning Xiao-qiu Yang 田明 Xiao-li Sun Li-qun Zhang 闫寿科 State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 China Beijing National Laboratory for Molecular Sciences Department of Polymer Science and Engineering & the Key Laboratory of Polymer Chemistry and Physics of Ministry of Education College of Chemistry and Molecular Engineering Peking University Beijing 100871 China Basic Research Service MOST Beijing 100862 China

The mechanical properties and phase morphologies of cis-1,4-butadiene rubber（BR） blended with polyethylene（PE） at different blend ratios were studied. The tensile test results show that the PE exhibits excellent reinforcing capabilities towards BR. Blending BR with PE results in a remarkable enhancement of tensile strength, modulus and the elongation at break simultaneously. An increment of tensile strength from 1.11 MPa to 16.26 MPa was achieved by incorporation of 40 wt% PE in the blends. The modulus and elongation at break of 40/60 PE/BR blends are also about 5 times higher than those of the pure BR treated under exactly the same conditions. The tear test indicates that the tear strength also increases with the increase of PE content. It reaches 58.38 MPa for the 40/60 PE/BR blend, which is approximately 10 times higher than that of the pure BR. Morphological study demonstrates that the PE forms elongated microdomains finely dispersed in the BR matrix when its content is over 30 wt%, which corresponds to the remarkably enhanced mechanical *** to the results, reinforcement mechanism of PE toward BR dependent on the microstructure has been discussed and two different mechanisms have been proposed.

关键词： Polyethylene Cis-1 4-butadiene rubber Blend Mechanical property Morphology

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调控聚氨酯聚集态结构制备高性能介电弹性体

高分子学报 2023年第2期54卷 266-276页

作者：刘苏亭王秀娟宁南英田明环渤海绿色化工应用技术协同创新中心、潍坊职业学院化学工程学院潍坊262737 橡塑材料与工程教育部重点实验室/山东省橡塑材料与工程重点实验室、青岛科技大学高分子科学与工程学院青岛266042 有机无机复合材料国家重点实验室、北京化工大学北京100029

通过退火保温调控聚氨酯(TPU)的相结构、结晶结构和氢键结构,进而调控其模量和介电常数(ε'),提高TPU的电驱动性能.使用扫描电子显微镜(SEM)和小角X射线(SAXS)研究TPU的结晶结构,基于红外光谱对TPU的氢键变化进行半定量分析,使用原子力... 详细信息

通过退火保温调控聚氨酯(TPU)的相结构、结晶结构和氢键结构,进而调控其模量和介电常数(ε'),提高TPU的电驱动性能.使用扫描电子显微镜(SEM)和小角X射线(SAXS)研究TPU的结晶结构,基于红外光谱对TPU的氢键变化进行半定量分析,使用原子力显微镜(AFM)研究TPU的微相分离结构.结果显示,退火温度和时间不同导致TPU的聚集态结构各异,对模量、ε'和电驱动性能产生了较为复杂的影响.低温(80℃)退火处理后,硬相分布于连续的软段相,且形成了较多软段结晶,相分离程度和氢键破坏程度提高.相比于高温(150℃)退火处理,低温退火后获得较高ε'的同时保持了较低的模量,从而产生较大电致形变.值得注意的是,低温退火条件下产生大范围的软段结晶,使得软段分子链之间排布紧密,导致TPU电击穿强度大幅度提升,得到具有高击穿强度、高电致形变的TPU介电弹性体材料.80℃退火处理6 h后,TPU的电击穿强度从退火处理前的25 kV/mm提高至32 kV/mm,最大电致形变从0.77%提高至3.3%,提高4.3倍.

关键词：聚氨酯介电弹性体结晶相分离电致形变

Microglia lactylation in relation to central nervous system diseases

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Neural Regeneration Research 2025年第1期20卷 29-40页

作者： Hui Yang nan Mo Le Tong Jianhong Dong Ziwei Fan Mengxian Jia Juanqing Yue ying Wang School of Pharmacy Hangzhou Normal UniversityHangzhouZhejiang ProvinceChina Department of Clinical Laboratory The Fourth Clinical Medical College of Zhejiang University of Traditional Chinese Medicine(Hangzhou First People’s Hospital)HangzhouZhejiang ProvinceChina College of Medical Veterinary and Life SciencesUniversity of GlasgowGlasgowUK Department of Orthopedics(Spine Surgery) the First Affiliated Hospital of Wenzhou Medical UniversityWenzhouZhejiang ProvinceChina Department of Pathology Affiliated Hangzhou First People’s HospitalWestlake University School of MedicineHangzhouZhejiang ProvinceChina Department of Clinical Research Center Affiliated Hangzhou First People’s HospitalWestlake University School of MedicineHangzhouZhejiang ProvinceChina

The development of neurodegenerative diseases is closely related to the disruption of central nervous system ***,as innate immune cells,play important roles in the maintenance of central nervous system homeostasis,injury response,and neurodegenerative *** has been considered a metabolic waste product,but recent studies are revealing ever more of the physiological functions of *** is an important pathway in lactate function and is involved in glycolysis-related functions,macrophage polarization,neuromodulation,and angiogenesis and has also been implicated in the development of various *** review provides an overview of the lactate metabolic and homeostatic regulatory processes involved in microglia lactylation,histone versus non-histone lactylation,and therapeutic approaches targeting ***,we summarize the current research on microglia lactylation in central nervous system diseases.A deeper understanding of the metabolic regulatory mechanisms of microglia lactylation will provide more options for the treatment of central nervous system diseases.

关键词： brain central nervous system glycolysis immune response inflammation lactate metabolism lactate lactylation microglia neurodegenerative diseases

Met-Controlled Allosteric Module of Neural Generation as A New Therapeutic Target in Rodent Brain Ischemia

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Chinese Journal of Integrative Medicine 2021年第12期27卷 896-904页

作者： LI Kang-ning ZHANG ying-ying YU Ya-nan WU Hong-li WANG Zhong Department of Traditional Chinese Medicine Beijing Tiantan HospitalCapital Medical UniversityBeijing(100070)China Institute of Basic Research in Clinical Medicine China Academy of Chinese Medical SciencesBeijing(100700)China

Objective To investigate a Met-controlled allosteric module(AM)of neural generation as a potential therapeutic target for brain *** We selected Markov clustering algorithm(MCL)to mine functional modules in the related target *** to the topological similarity,one functional module was predicted in the modules of baicalin(BA),jasminoidin(JA),cholic acid(CA),compared with I/R model *** functional module included three genes:Inppl1,Met and Dapk3(IMD).By gene ontology enrichment analysis,biological process related to this functional module was *** functional module participated in generation of *** blotting was applied to present the compound-dependent regulation of ***-immunoprecipitation was used to reveal the relationship among the three *** used IF to determine the number of newborn neurons between compound treatment group and ischemia/reperfusion *** expressions of vascular endothelial growth factor(VEGF)and matrix metalloproteinase 9(MMP-9)were supposed to show the changing circumstances for neural generation under cerebral *** Significant reduction in infarction volume and pathological changes were shown in the compound treatment groups compared with the I/R model group(Pying pharmacological mechanisms in cere

关键词： allosteric module InppM-Met-Dapk3 generation of neurons brain ischemia

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基于SM2和DNA的图像加密算法

陕西科技大学学报 2025年第1期43卷 203-210页

作者：唐亦昕张英男武警工程大学密码工程学院密码与信息安全武警部队重点实验室陕西西安710016

近年来,随着互联网的全面普及,公民对信息安全和隐私保护提出了新的更高的要求,为了保护公民的数据安全,并且满足“打赢新时代网络战争”的要求,对图像加密算法的研究与实现进行深入的研究,提出了一种基于国密SM2数字信封和脱氧核糖核酸... 详细信息

近年来,随着互联网的全面普及,公民对信息安全和隐私保护提出了新的更高的要求,为了保护公民的数据安全,并且满足“打赢新时代网络战争”的要求,对图像加密算法的研究与实现进行深入的研究,提出了一种基于国密SM2数字信封和脱氧核糖核酸(Deoxyribonucleic acid,DNA)编码的图像加密技术,将图像编码技术、公钥技术、口令保护技术相结合.在该算法中,通过使用Python重点实现了密钥空间的复杂性、图像的鲁棒性、随机性、低相关性,同时对图像的直方图进行了分析,研究结果表明,在实现公钥加密算法国产化替代的同时,增强了加密的安全性.

关键词： SM2数字信封 Chen超混沌 Logistic混沌鲁棒性脱氧核糖核酸(DNA)