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Chinese Journal of Polymer Science 2010年第1期28卷 63-68页

作者：唐晓林张红东 The Key Laboratory of Molecular Engineering of polymers Ministry of Educationand Department of Macromolecular ScienceFudan University

The generalized two-dimensional correlation analysis based on time-resolved light scattering patterns （2D TRLS） has been employed to study the phase separation process of an epoxy-amine-polyethersulfone blend in which the secondary phase separation takes place. The results of the 2D TRLS provided more detailed information that was not readily observed in the 1D TRLS patterns. （i） During the first process of phase separation, the sequential order of coarsening in size of the domains among the larger and smaller ones has been reversed between the diffusion regime and the hydrodynamic regime. （ii） The change of the larger domains in size, due to the hydrodynamic flow in the late stage of the first phase separation process, keeps on taking place earlier than that of the new domains appeared in the secondary phase separation process. （iii） During the secondary phase separation process the size growth of the smaller domains takes place earlier than that of the larger ones, probably due to the assumption that the coarsening mode could decrease the interface tension more quickly.

关键词： Two-dimensional (2D) correlation analysis Time-resolved light scattering (TRLS) Phase separation Blend

Sorting Semiconducting Single-Walled Carbon Nanotubes by Water-Soluble Polyfluorene Assisted Electrophoresis and Its Application in Field-effect Transistors

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Chinese Journal of Chemistry 2015年第7期33卷 756-764页

作者： Haoyun Zhu Weizhi Wang State Key Laboratory of Molecular Engineering of polymers Collaborative Innovation Center of Polymers and Polymer Composite Materials Department of Maeromoleeular Science Fudan University Shanghai 200433 China

We report a considerably promising method based on agarose gel electrophoresis （AGE） to separate single-walled carbon nanotubes by adding a water-soluble polyfluorene （w-PFO） as surfactant into the agarose gel. In this effective method, the AGE/w-PFO gel network will trap more semiconducting single-walled carbon nanotubes （SWNTs） with the assistance ofw-PFO, for the strong interaction between w-PFO and semiconducting species. The optical absorbance, photoluminescence emission and resonant Raman scattering characterization were used to ver- ify the separation effect. The purity of separated semiconducting species is as high as （98±1）%. The demonstrated field effect transistors give the on/off ratio and mobility about 27000 and 10.2 cm^2·V^-1·s^-1, respectively.

关键词： agarose gel electrophoresis field effect transistors semiconducting single-walled carbon nanotubes water-soluble polyfluorene

Solitons and defects in nematic liquid crystals under a simple shear flow and in a static external magnetic field

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Chinese Physics B 2008年第7期17卷 2600-2609页

作者：罗开富蒋秀丽杨玉良 department of Macromolecular Science Key Laboratory of Molecular Engineering of Polymers of State Ministry EducationFudan University

Under a simple shear flow and in a static external magnetic field, the production of defects in the director-aligning regime of nematic liquid crystals has been investigated in terms of the Leslie-Ericksen theory. The equation of motion of the nematic director, which conforms to the driven over-damped sine-Gordon equation, has a soliton solution of the amplitude w. We show that the stationary state with the director uniformly oriented at a Leslie angle is only a metastable state and the potential, which governs the motion of the director, has a nmnber of stable stationary states. For a strong magnetic field, the higher energy barrier between the stable and unstable states leads the director to be locked along the magnetic field direction. However, at the appropriate shear rate and magnetic field the defects, which appear as a stable solitary solution, can be nucleated from a uniformly aligned nematic liquid crystal. We have calculated the stationary travelling velocity of the solitary waves and the distance between a pair of defects.

关键词： liquid crystals defects solitons

Polymeric partners breathe together: using gas to direct polymer self-assembly via gas-bridging chemistry

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Science China Chemistry 2022年第7期65卷 1401-1410页

作者： Zehao Gong Yixin Wang Qiang Yan State Key Laboratory of Molecular Engineering of polymers Department of Macromolecular ScienceFudan University200433China

The quest for a general and facile way to regulate polymer self-assembled nanostructures with low-to high-order ergodicity is an eternal theme in soft nanoparticle fabrication. Here we present an unprecedented gas-bridging strategy that allows to use gas to direct polymer self-assembly in continuous and tunable manners. Such system comprises a partner of frustrated Lewis polymers with bulky Lewis acid and base groups. They can together “breathe in” external gases to form gas-bridged structures between the two complementary moieties, which drive their mutual complexation and assemble into polymer nanoparticles of diverse geometries and dimensionalities. This strategy is applicable to a broad family of gas substances including but not limited to carbon oxides, nitrogen oxides, sulfur oxides, and even olefins;moreover, tailoring gas types and levels can dictate distinct assembling evolutionary pathways and deformable behaviors among spherical, fibrous, polymersomal, tubesomal and cubosomal morphologies. We also discover that the gas-based bonding chemistry is the mechanistic basis underlying the phase transitional control and phase window regulation. This will open a new direction of making bespoke polymer nanostructures with gas.

关键词： gas-bridging bond Lewis pair polymer dynamic covalent chemistry self-assembly tunable nanostructure

Thermo-and photo-driven soft actuators based on crosslinked liquid crystalline polymers

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Chinese Physics B 2016年第9期25卷 24-36页

作者：顾伟韦嘉俞燕蕾 department of Materials Science Fudan University State Key Laboratory of Molecular Engineering of polymers Fudan University

Crosslinked liquid crystalline polymers（CLCPs） are a type of promising material that possess both the order of liquid crystals and the properties of polymer *** anisotropic deformation of the CLCPs takes place when the mesogens experience order to disorder change in response to external stimuli; therefore,they can be utilized to fabricate smart actuators,which have potential applications in artificial muscles,micro-optomechanical systems,optics,and energyharvesting *** this review the recent development of thermo-and photo-driven soft actuators based on the CLCPs are summarized.

关键词： actuators crosslinked liquid crystalline polymers deformation

Utilization of Trimethylolpropane Based Hyperbranched Poly(Amine-Ester) as New Polymeric Admixture

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Open Journal of Organic Polymer Materials 2012年第2期2卷 23-28页

作者： Amal Amin Ibrahim Ahmed El-Sayed Abdel-Magied Mohamed Sayed Selim Magdy Mohamed Hussein Ayoub Organic Chemistry department Menoufiya University Shebin El-Kom Egypt polymers and pigments department National Research Center Dokki Giza Egypt

Hyperbranched poly(amine-ester) (HBPAE) was synthesized via pseudo-one-step process between trimethylolpropane as a core molecule and N, N-diethylol-3-amine methylpropionate as the AB2 branched monomer. The prepared polymer was analyzed by IR, GPC, 1H-NMR and thermal analysis (TGA and DSC). The performance of the polymer in cement was tested by measuring the effect of 1, 3 and 5 wt% of HBPAE solutions on the properties of Ordinary Portland Cement. Water of consistency, setting times, bulk density, apparent porosity, compressive strength and combined water content of the polymer/cement pastes were studied. The results showed that water of consistency and apparent porosity decreased while setting times, compressive strength, combined water and bulk density increased with the polymer addition.

关键词： Hyperbranched polymers Poly(Amine-Ester) Ordinary Portland Cement Compressive Strength

Study of damage behavior and repair effectiveness of patch repaired carbon fiber laminate under quasi-static indentation loading

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Defence Technology（防务技术） 2024年第4期34卷 29-41页

作者： Alok Kumar Chinmaya Kumar Sahoo A.Arockiarajan department of Applied Mechanics Indian Institute of Technology MadrasChennai 600036India

Damage caused due to low-velocity impacts in composites leads to substantial deterioration in their residual strength and eventually provokes structural *** work presents an experimental investigation on the effects of different patch and parent laminate stacking sequences on the enhancement of impact strength of Carbon Fiber Reinforced polymers(CFRP)composites by utilising the adhesively bonded external patch repair *** evolution study is also performed with the aid of Acoustic Emission(AE).Two different quasi-isotropic configurations were selected for the parent laminate,viz.,[45°/45°/0°/0°]s and[45°/0°/45°/0°]*** Static Indentation(QSI)test was performed on both the pristine laminates,and damage areas were detected by using the C-scan inspection *** laminates were repaired by using a single-sided patch of two different configurations,viz.,[45°/45°/45°/45°]and[45°/0°/0°/45°],and employing a circular plug to fill the damaged *** different combinations of repaired laminates with two configurations of each parent and patch laminate were produced,which were further subjected to the QSI *** results reveal the effectiveness of the repair method,as all the repaired laminates show higher impact resistance compared to the respective pristine *** of[45°/0°/0°/45°]configuration when repaired by taking[45°/45°/0°/0°]s and[45°/0°/45°/0°]s as parents exhibited 68%and 73%higher peak loads,respectively,than the respective pristine ***,parent and patch of configuration[45°/0°/45°/0°]s and[45°/0°/0°/45°],respectively,attain the highest peak load,whereas[45°/45°/0°/0°]s and[45°/45°/45°/45°]combinations possess the most gradual decrease in the load.

关键词： Carbon fiber reinforced polymers(CFRP) Quasi-isotropic laminate Quasi static indentation(QSI) Acoustic emission(AE) Composite repair

The Application of Cellulose Nanocrystals Modified with Succinic Anhydride under the Microwave Irradiation for Preparation of Polylactic Acid Nanocomposites

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Journal of Renewable Materials 2021年第6期9卷 1127-1142页

作者： Ewa Szefer Agnieszka Leszczyńska Edyta Hebda Krzysztof Pielichowski department of Chemistry and Technology of polymers Cracow University of TechnologyKrakow31-155Poland

The aim of this work was to use cellulose nanocrystals that were obtained by hydrolysis in phosphoric acid solution and further modified with succinic anhydride in the microwave field for PLA reinforcement.A series of allbionanocomposites containing unmodified and surface modified cellulose nanocrystals with CNC content in the range of 1–3%_(w.t.) were obtained by melt blending and tested by XRD,SEM,DSC and DMA to investigate the effect of surface esterification of CNCs on the structure,morphology,dynamic mechanical properties of bionanocomposites,as well as phase transitions of PLA in the presence of cellulosic *** investigations showed the highest increase of storage modulus by ca.7%(335 MPa at 25℃)in the glassy state of PLA for 2%_(w.t.)of unmodified ***,addition of 2%_(w.t.)of succinylated CNCs caused the highest increase of the onset of glass transition temperature(by 6.2℃)thus widening the temperature range of biocomposite *** increase of glass transition temperature indicates the strongest interfacial interactions due to improved miscibility of surface modified nanocrystals and thus good dispersion of additive in PLA matrix providing high interface.

关键词： Cellulose nanocrystals CNC whiskers surface modification succinic anhydride PLA polylactic acid nanocomposites

One-step polymerized lanthanide-based polystyrene microsphere for sensitive lateral flow immunoassay

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Journal of Rare Earths 2021年第1期39卷 11-18,I0001页

作者： Zhenhua Li Qingyun Liu Yongfang Li Wei Yuan Fuyou Y.Li State Key Laboratory of Molecular Engineering of polymers Department of ChemistryFudan UniversityShanghai200433China

Lateral flow immunoassays(LFIAs)provide a powerful tool for rapid real-time assay of cancer biomarkers,which is vital for cancer detection and treatment ***-based LFIAs is one of the most widely used methods,especially Eu(Ⅲ)chelates,which possess distinctive and attractive characteristics,such as time-resolved fluorescence and large Stokes ***,we adopted a new onestep mini-emulsion polymerization method to synthesize carboxyl-modified fluorescent microsphere(OS-EuCM),which shows good stability,resistance to non-specific adhesion and uniform particle size distribution compared with traditional microspheres synthesized through the swelling *** from the above advantages,OS-EuCM was successfully used in LFIAs to detect tumor marker Alpha-fetoprotein with high sensitivity and selectivity in concentration as high as 320 ng/mL,as well as a detection limit of 0.683 ng/mL This lanthanide-based microsphere holds great potential for rapid pointof-care screening and clinical application.

关键词： Eu(Ⅲ)chelate Polystyrene microsphere Mini-emulsion polymerization Lateral flow immunoassays Alpha-fetoprotein Rare earths

Biological Stimuli-responsive Polymer Systems:Design,Construction and Controlled Self-assembly

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Chinese Journal of Polymer Science 2018年第3期36卷 347-365页

作者： Miao-Miao Xu Ren-Jie Liu Qiang Yan Key Laboratory of Molecular Engineering of polymers Department of Macromolecular ScienceFudan UniversityShanghai 200433China

Biological stimuli-responsive polymers have increasingly attracted attention in recent years because it can satisfy many requirements of applications related with human body while traditional systems do not *** to the importance of this burgeoning field,great efforts have been devoted and,up to now,polymer chemists have made a remarkable success in this prospective research *** this review,we systematically generalize the present state of biological stimuli-responsive polymer *** highlight several representative examples to specify the current problems and look ahead a clear sense of direction in this area.

关键词： Biological stimuli Responsive polymer Controlled self-assembly Biomedicine