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Chinese Journal of Polymer Science 2013年第9期31卷 1321-1328页

作者： Cong-de Qiao Shi-chun jiang xiang-ling ji Li-jia An School of Material Science & Engineering Shandong Polytechnic University School of Material Science & Engineering Tianjin University State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences

The melting and crystallization behaviors of poly（e-caprolactone）（PCL） ultra-thin films with thickness from 15 ran to 8 nm were studied by AFM technique equipped with a hot-stage in real-time. It was found that melting can erase the spherulitic structure for polymer film with high thickness. However, annealing above the melting point can not completely erase the tree-like structure for the thinner polymer film. Generally, the structure formation of thin polymer films of PCL is controlled not only by melting and crystallization but also by dewetting during thermal annealing procedures, and dewetting predominates in the structure formation of ultra-thin films. However, the presence of tree-like morphology at 75 ℃ may be due to the strong interaction between PCL and mica surface, which may stick the PCL chains onto the mica surface during thermal annealing process. Moreover, the growth of the dendrites was investigated and it was found that crystallization is followed from a dewetted sample, and the branches did not grow with the stems. The crystallization of polymer in the ultra- thin films is a diffusion-controlled process. Both melting and crystallization behaviors of PCL in thin films are influenced by film thickness.

关键词： PCL Ultra-thin film Melting Crystallization Dewetting.

SYNTHESIS AND PROPERTIES OF BIFUNCTIONAL MAGNETIC-OPTICAL NANOMATERIALS:Fe_2O_3@PDMAEMA-CAPPED Ⅱ－Ⅵ SEMICONDUCTOR QUANTUM DOTS NANOCOMPOSITES

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Chinese Journal of Polymer Science 2013年第9期31卷 1233-1241页

作者： Na-na Zhao Wei Nie Jun Mao Wei-cai Wang xiang-ling ji State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences

A facile route to synthesize a new type of multifunctional nanocomposites is reported. Here, PDMAEMA （poly[2- （dimethylamino）ethyl] methacrylate） is a key macromolecule serving as a bridge between magnetic FeaO3 nanoparticles and luminescent quantum dots. Both Fe203 nanoparticles and II-VI semiconductor quantum dots with a narrow size distribution are synthesized through a two-phase thermal approach. Subsequently, the atom transfer radical polymerization （ATRP） technique was applied to prepare magnetic Fe203@PDMAEMA core-shell nanoparticles. The thickness of PDMAEMA shell can be easily controlled by adjusting the reaction time. Finally, the ligand exchange method was exploited to modify II-VI quantum dot with amine-containing polymer of PDMAEMA, which led to quantum dot securely bound by Fe203@PDMAEMA core-shell nanoparticle to form a multifunctional nanocomposite. The resulting nanocomposite remains variable emission by tuning the II-VI semiconductor type and particle size and shows/arc at 49 kA/m and Tb at 16 K from Fe2O3 nanoparticles. The self-assembled behavior for the resulting samples is also discussed.

关键词： Bifunctional nanocomposite Magnetic-optical PDMAEMA Semiconductor ATRP Two-phase method.

Molecular Weight Dependence of Associative Behavior in Polyimide/DMF Solutions

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Chinese Journal of Polymer Science 2020年第6期38卷 629-637页

作者： Hong-xiang Chen En-Song Zhang Mei Hong Wei Liu Xue-Min Dai Quan Chen Xue-Peng Qiu xiang-ling ji State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei230026China Laboratory of Polymer Composites and Engineering Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

Eight 6FDA-TFDB polyimide(PI)samples with absolute molecular weights ranging from 1.25 × 10^5 g mol^-1 to 3.11 × 10^5 g mol^-1 are obtained by precipitation *** experiments are conducted to determine the influence of molecular weight on the associating behavior of PI in A/X-dimethylformamide(DMF)solutions in a broad volume fraction,including abnormal steady shear flow,solution heterogeneity,and scaling *** flow behaviors,i.e.,multi-region shear thinning and weak shear thickening,are studied,and these behaviors have not been reported in *** heterogeneity of PI/DMF solutions is examined by dynamic rheological *** plotting qsp versus four concentration regions of l-IV can be distinguished for all PI samples with various molecular *** scaling results in different concentration regions are in good agreement with the associative polymer theory proposed by Rubinstein and *** scaling exponents do not show molecular weight dependence in concentration regions I and *** concentration regions Ⅲ and Ⅳ,the scaling exponents change little when the molecular weight is below 242 k but increase when the molecular weight increases from 242 k to 311 *** work can help us to understand polyimide solution properties from dilute to semidilute entangled solutions,and will guide the polyimide solution preparation for different processing.

关键词： Soluble polyimide Molecular weight Rheology Associative polymer Scaling behavior

INTERACTION BETWEEN POLY (ETHYLENE OXIDE) AND SILICA NANOPARTICLES IN DILUTE SOLUTIONS

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Chinese Journal of Polymer Science 2013年第9期31卷 1290-1298页

作者： Da-peng Wang Mu-quan Yang Zhi-xin Dong Shu-qin Bo xiang-ling ji State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences

A mixed system that includes poly（ethylene oxide）（PEO） and silica （SiO2） nanoparticles is prepared using two mixing methods. The interaction between PEO and the SiO2 nanoparticles in the dilute basic solution is investigated using the dynamic tight scattering （DLS） and isothermal titration calorimetry （ITC） techniques. The DLS results show qualitatively that SiO2 nanoparticles interact with both random coils and aggregates of PEO through hydrogen bonding, and PEO-SiO2 complexes are formed. The degree of disaggregation of aggregates of PEO is readily adjusted by changing the concentration of SiO2 nanoparticle suspensions. Moreover, the ITC results also certify quantitatively the interaction between PEO and SiO2 nanoparticle, and give the evidence of formation of PEO-SiO2 complex.

关键词： PEO SiO2 nanoparticles Hydrogen bonding Disaggregation Mixing method Depletion interaction.

Hofmeister Effect on Thermo-responsive Poly(N-isopropylacrylamide)Hydrogels Grafted on Macroporous Poly(vinyl alcohol) Formaldehyde Sponges

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Chinese Journal of Polymer Science 2020年第3期38卷 257-267,I0006页

作者： Kai Shi Di Sha jiu-Duo Xu Xu Yang Bao-Long Wang Yan-Xiong Pan xiang-ling ji State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China University of Chinese Academy of Sciences Beijing 100049China

In this work,the Hofmeister effects of nine kinds of anions at different concentrations on the lower critical solution temperature(LCST)of the macroporous thermo-responsive poly(N-isopropylacrylamide)grafted poly(vinyl alcohol)formaldehyde(PVF-g-PNIPAM)hydrogels are investigated with differential scanning calorimetry(DSC).Four kinds of anions with strong hydration,including CO3^2–,SO4^2–,S2 O3^2–,and F^–,and four kinds of anions with weak hydration,including Br^–,NO3^–,I^–,and ClO4^–,and Cl^–as a medium anion are systematically studied and found to demonstrate the effects of the residual hydroxyl groups and network structure of PVF on the LCST values of PVF-g-PNIPAM hydrogels in comparison with that of neat *** the one hand,the existence of hydroxyl groups on PVF backbone promotes the solubility of grafted PNIPAM due to their hydrophilicity and hydrogen-bond interactions with *** the other hand,the network structure of as-prepared samples restricts free movements of grafted PNIPAM chains,which results in the increase of LCST *** addition,the difference of grafting percentage also influences the variation of LCST values of PVF-g-PNIPAM hydrogels under salt concentration.

关键词： Hofmeister effect Thermo-responsive PVF-g-PNIPAM Hydroxyl groups Network structure

Preparation and Properties of High-performance Polyimide Copolymer Fibers Derived from 5-Amino-2-(2-hydroxy-5-aminobenzene)-benzoxazole

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Chinese Journal of Polymer Science 2019年第5期37卷 478-492页

作者： Xue-Min Dai Hong Gao Ran Zhang Zhi-Jun Du Tong-Fei Shi xiang-ling ji Xue-Peng Qiu Yong-Feng Men State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of Sciences Polymer Composites Engineering Laboratory Changchun Institute of Applied ChemistryChinese Academy of Sciences University of Chinese Academy of Sciences China Academy of Space Technology

A series of polyamic acid copolymers(co-PAAs) with para-hydroxyl groups was synthesized using two diamine monomers,namely p-phenylenediamine(p-PDA) and 5-amino-2-(2-hydroxy-5-aminobenzene)-benzoxazole(m-pHBOA), of different molar ratios through copolymerization with 3,3′,4,4′-biphenyltetracarboxylic dianhydride(BPDA) in N,N-dimethyacetamine(DMAc). The co-PAA solutions were used to fabricate fibers by dry-jet wet spinning, and thermal imidization was conducted to obtain polyimide copolymer(coPI) fibers. The effects of the m-pHBOA moiety on molecular packing and physical properties of the prepared fibers were *** transform infrared(FTIR) spectroscopic results confirmed that intra/intermolecular hydrogen bonds originated from the hydroxyl group and the nitrogen atom of the benzoxazole group and/or the hydroxyl group and the oxygen atom of the carbonyl group of cyclic imide. As-prepared PI fibers displayed homogenous and smooth surface and uniform diameter. The glass transition temperatures(Tgs) of PI fibers were within 311-337 °C. The polyimide fibers showed 5% weight loss temperature(T5%) at above 510 °C in air. Twodimensional wide-angle X-ray diffraction(WXRD) patterns indicated that the homo-PI and co-PI fibers presented regularly arranged polymer chains along the fiber axial direction. The ordered molecular packing along the transversal direction was destroyed by introducing the m-pHBOA moiety. Moreover, the crystallinity and orientation factors increased with increasing draw ratio. Small-angle X-ray scattering(SAXS) results showed that it is beneficial to reduce defects in the fibers by increasing the draw ratio. The resultant PI fibers exhibited excellent mechanical properties with fracture strength and initial modulus of 2.48 and 89.73 GPa, respectively, when the molar ratio of p-PDA/m-pHBOA was 5/5 and the draw ratio was 3.0.

关键词： Polyimide fiber Phenylenebenzoxazole Hydroxyl group Hydrogen bonding

聚乙烯树脂的连续自成核与退火热分级实验参数优化及其与逐步结晶热分级对比

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高分子学报 2015年第3期25卷 326-330页

作者：薛彦虎薄淑琴姬相玲中国科学院长春应用化学研究所高分子物理与化学国家重点实验长春130022 中国科学院大学北京100049

以支化聚乙烯树脂为研究对象,研究连续自成核与退火热分级实验中,初始温度点(Ts)、升温降温速率、温度间隔(ΔT)和等温时间等实验参数对分级结果的影响,得到了一系列优化的实验参数或范围,为连续自成核与退火热分级方法的实际应用推广... 详细信息

以支化聚乙烯树脂为研究对象,研究连续自成核与退火热分级实验中,初始温度点(Ts)、升温降温速率、温度间隔(ΔT)和等温时间等实验参数对分级结果的影响,得到了一系列优化的实验参数或范围,为连续自成核与退火热分级方法的实际应用推广提供参考.并将连续自成核与退火(SSA)和逐步结晶(SC)两种热分级的实验结果进行了比较.

关键词：聚乙烯热分级实验参数优化

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体积排除色谱技术在高分子表征中的应用

高分子学报 2021年第9期52卷 1221-1244页

作者：刘巍刘勇刚姬相玲中国科学院长春应用化学研究所高分子物理与化学国家重点实验室长春130022

体积排除色谱(SEC)也称为凝胶渗透色谱(GPC),是利用多孔填料色谱柱将溶液中的高分子按照流体力学体积大小进行分离的一种液相色谱技术,主要用于测定各种天然和合成高分子的平均分子量及分子量分布.多检测SEC技术可同时获得经色谱柱分离... 详细信息

体积排除色谱(SEC)也称为凝胶渗透色谱(GPC),是利用多孔填料色谱柱将溶液中的高分子按照流体力学体积大小进行分离的一种液相色谱技术,主要用于测定各种天然和合成高分子的平均分子量及分子量分布.多检测SEC技术可同时获得经色谱柱分离后高分子各级分的含量、分子量、均方根回转半径、流体力学半径、特性黏数等参数,进而推断高分子在溶液中的形态和链构象.本文首先介绍了SEC分离的基本原理,即由熵驱动的高分子在多孔填料内外分配达到平衡的体积排除机理,接着总结了SEC的一些实验方法和技巧,并详细阐述了SEC在高分子的分子量及其分布测定、定量分析、链构象与刚柔性、支化结构表征、链构象转变等方面的应用,最后展望了SEC的发展趋势.

关键词：体积排除色谱高分子表征分子量及其分布构象

Regulation and function of endoplasmic reticulum autophagy in neurodegenerative diseases

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Neural Regeneration Research 2025年第1期20卷 6-20页

作者： Xiu-Yun Zhao De-En Xu Ming-Lei Wu ji-Chuan Liu Zi-ling Shi Quan-Hong Ma Department of Neurology and Clinical Research Center of Neurological Disease the Second Affiliated Hospital of Soochow UniversitySuzhouJiangsu ProvinceChina Institute of Neuroscience&jiangsu Key Laboratory of Translational Research and Therapy for Neuro-Psycho-Diseases Soochow UniversitySuzhouJiangsu ProvinceChina Department of Neurology Jiangnan University Medical CenterWuxiJiangsu ProvinceChina

The endoplasmic reticulum,a key cellular organelle,regulates a wide variety of cellular *** reticulum autophagy,one of the quality control systems of the endoplasmic reticulum,plays a pivotal role in maintaining endoplasmic reticulum homeostasis by controlling endoplasmic reticulum turnover,remodeling,and *** this review,we briefly describe the endoplasmic reticulum quality control system,and subsequently focus on the role of endoplasmic reticulum autophagy,emphasizing the spatial and temporal mechanisms underlying the regulation of endoplasmic reticulum autophagy according to cellular *** also summarize the evidence relating to how defective or abnormal endoplasmic reticulum autophagy contributes to the pathogenesis of neurodegenerative *** summary,this review highlights the mechanisms associated with the regulation of endoplasmic reticulum autophagy and how they influence the pathophysiology of degenerative nerve *** review would help researchers to understand the roles and regulatory mechanisms of endoplasmic reticulum-phagy in neurodegenerative disorders.

关键词： autophagy endoplasmic reticulum endoplasmic reticulum autophagy endoplasmic reticulum quality control system endoplasmic reticulum receptors endoplasmic reticulum-associated degradation neurodegeneration neurodegenerative disease selective autophagy unfolded protein response

采用流变学方法研究聚酰胺酸6FDA-TFDB溶液的降解行为

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高分子学报 2017年第9期27卷 1497-1505页

作者：张恩菘代学民刘学杨文轲刘巍董志鑫邱雪鹏姬相玲中国科学院长春应用化学研究所高分子物理与化学国家重点实验室中国科学院大学北京100049 高分子复合材料工程实验室长春130022

合成了一种聚酰胺酸6FDA-TFDB溶液,利用流变仪研究其在不同影响因素(如:温度、升温速率、溶剂含水量等)下的流变行为,发现聚酰胺酸溶液的降解在高温区和低温区存在不同的行为.通过Andrade公式获得不同条件下聚酰胺酸溶液的黏流活化能,... 详细信息

合成了一种聚酰胺酸6FDA-TFDB溶液,利用流变仪研究其在不同影响因素(如:温度、升温速率、溶剂含水量等)下的流变行为,发现聚酰胺酸溶液的降解在高温区和低温区存在不同的行为.通过Andrade公式获得不同条件下聚酰胺酸溶液的黏流活化能,并比较其差异,同时对溶剂水含量在不同温度区域下对聚酰胺酸降解速率的影响也进行了深入的分析,从而建立一种半定量比较不同条件下聚酰胺酸溶液降解速率的方法.

关键词：聚酰胺酸降解行为流变仪黏度黏流活化能