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Chinese Journal of Polymer Science 2018年第4期36卷 528-535页

作者： Jing-Jing Wu Jin Zhou Jing-Qiu Rong Yao Lu Hui Dong Hai-Yin Yu Jia-Shan Gu College of Chemistry and Materials Science Anhui Normal University Department of Material and Chemical Engineering Chizhou University

Branch length and density have critical effects on membrane performances; however, it is regarded to be traditionally difficult to investigate the relationship due to the uncontrolled membrane modification methods. In this study, zwitterionic polymer with controlled grafting branch chain length（degree of polymerization） and grafting density（grafting chains per membrane area） was tethered to the microporous polypropylene membrane surface based on the combination of reversible addition-fragmentation chain transfer（RAFT） polymerization technique with click reaction. The modified membranes were tested by filtrating protein dispersion to highlight the correlations of branch chain length and grafting density with the membrane permeation performances. The pure water flux, the flux recovery ratio are positively and significantly, and the irreversible fouling negatively and significantly correlated with grafting density. These results demonstrate that the larger the coverage of the membrane with poly{[2-（methacryloyloxy）ethyl]-dimethyl-（3-sulfopropyl） ammonium hydroxide}（PMEDSAH）, the higher the pure water flux and the higher the flux recover ratio, and the lower the irreversible fouling, which shows that high grafting density is favorable to fouling reducing.

关键词： grafting branch length grafting density Polypropylene membrane Protein fouling Zwitterionic polymer

Physical Insight for grafting Polymer Chains onto the Substrate via Computer Simulations:Kinetics and Property

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Chinese Journal of Polymer Science 2022年第7期40卷 817-833页

作者： Chi-Xin Liang Hui Lu Bai-Ying Huang Ji-Yuan Xing Feng-Long Gu Hong Liu School of Chemistry South China Normal UniversityKey Laboratory of Theoretical Chemistry of Environment Ministry of EducationGuangzhou510006China State Key Laboratory of Supramolecular Structure and Materials Institute of Theoretical ChemistryCollege of ChemistryJilin UniversityChangchun130023China State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China

Molecules adsorbed or attached on a surface is a quite basic phenomenon in numerous chemical or biological ***-onto is considered as a feasible way to achieve *** grafting reaction is essentially controlled by the diffusion of the molecules,thus it is more likely a physical issue,instead of a chemical *** of the experimental difficulty in measuring the properties of surface-attached molecules(e.g.,the polymeric molecules),the surface-bound molecules are often assumed as with the same properties as that of the start feeding ones in *** assumption was even used to guide further characterization,while it is proved to be invalid by different quantifying ***,an effective prediction for the properties of surface-bound molecules is still *** on a microscopic level and a dynamic perspective,the grafting process onto a flat substrate with polydisperse feeding polymeric molecules is investigated in-depth by coarse-grained Brownian dynamics simulation as well as model *** find from simulations that for the final grafting densityσ_(g)and the mean chain length of start feeding molecules,the dependence ofσ_(g)-^(γ)with the constant exponential factorγmay be a determined rule for one-end functionalized flexible linear polymer chains grafting on the flat *** grafting-onto is a multiple interplayed process,our simulation study indicates that there is an optimized initial concentration of start feeding molecules for achieving high grafting density of surface-bound *** also propose a correctional equation to quantitatively predict the molecular weight distribution(MWD)of surface-bound polymeric molecules,which may be effective for predicting the MWD of the surface-bound ones in specific *** simulation study helps to better understand the kinetics of grafting-onto process,and serves as a theoretical guide to achieve the precise design of surface modification materials vi

关键词： grafting-onto grafting density Polydisperse Molecular weight distribution

Controllable Synthesis of a Well-defined Polypropylene grafted Silica Nanoparticles and Its Effect on Crystallization Behavior of Polypropylene

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Chinese Journal of Polymer Science 2022年第11期40卷 1411-1421页

作者： Wei-Long Ju Shao-Fan Li Yun-Lan Su Du-Jin Wang Key Laboratory of Engineering Plastics Beijing National Laboratory for Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China

Well-defined polypropylene grafted silica nanoparticles(PP-g-SiO_(2))were prepared through the reaction of maleic anhydride grafted polypropylene(PP-g-MAH)with amino-functionalized silica(SiO_(2)-NH_(2))by the'grafting-to'*** grafting density of PP-g-SiO_(2) is found to be controlled by the concentration of silane coupling agent 3-[2-(2-aminoethylamino)ethyl amino]propyl trimethoxy silane(TAMS).The maximum grafting density of grafted PP-g-MAH chains with molecular weight of 9100 g/mol could reach 0.34 chains/nm~2,when the critical concentration of TAMS was 0.0194 mol/*** critical concentration of TAMS can be explained by the maximum amounts of primary amino groups,which can totally react with PP-g-MAH on the surface of SiO_(2)-NH_(2),when the silane monolayer is *** synthesized PP-g-SiO_(2)with different molecular weights was mixed with PP by solution mixing to form a series of *** crystallization temperature(T_(c))of nanocomposites increased significantly with the particle *** PP-g-SiO_(2) with high molecular weight of grafted chains exhibits a high nucleation ability at 1 wt%nanoparticle loading in PP/PP-g-SiO_(2)*** summary,we provide an effective method to synthesize the well-defined PP-g-SiO_(2)with controlled grafting density,which shows excellent nucleation ability.

关键词： Polypropylene grafted silica nanoparticles grafting density grafting to Crystallization behavior

A Facile Method to Form a Densely Grafted PEO-b-P4VP Brush on Gold Surface

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Chinese Journal of Chemistry 2012年第8期30卷 1729-1734页

作者：杨倩周常明陈旺方佳节陈道勇 The State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityHandan Road 220Shanghai 200433China

Here we report a facile method for the preparation of a PEO113-b-P4VP93 brush on gold surface with a grafting density as high as 1.32 chains/nm2; the P4VP blocks were physically adsorbed on gold surface forming an inner layer while the PEO blocks stretched towards the solution forming PEO brush. PEOl13-b-P4VPq3 micelles with P4VP core and PEO shell formed in methanol/water mixed solvents were used as the precursor. By adsorbing PEOII3-b-P4VP93 micelles from pure water, in which the density of the micelles is the largest, maximum amount of the micelles was adsorbed onto gold surface, and the adsorbed micelles existed as individual domains on the surface To prepare the polymer brush with a density as high as possible, we annealed the adsorbed micelles by metha- nol/water mixed solvent at the volume fraction of methanol （VF） of 20%, which was the proper proportion at which the core-forming P4VP chains began to be flexible but the integrity of the micelles was remained. At this volume fraction, almost all the adsorbed micelles originally existing as individual domains were transformed into a dense polymer brush.

关键词： micelle adsorption solvent annealing diblock copolymer brush grafting density

Preparation and Performance of Collagen Modified Polyester Used as Implantable Artificial Hair

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Journal of Donghua University(English Edition) 2018年第1期35卷 38-42页

作者： CHEN Ying YU Jinze TANG Jintian Department of Material Science and Engineering Beijing Key Laboratory of Clothing Materials R&D and AssessmentBeijing Institute of Fashion TechnologyBeijing 100029China Institute of Medical Physics and Engineering Department of Engineering PhysicsTsinghua UniversityBeijing 100084China College of Textile and Fashion Qingdao UniversityQingdao 266071China

The implantable artificial hair was prepared by grafting collagen on the surface of poly(ethylene terephthalate)(PET)to improve its *** acid(AAc)was used to modify the surface properties of PET firstly,and then collagen was grafted on the PET-AAc *** concentration of collagen solution was discussed to graft more collagen on PET *** were well characterized by scanning electron microscopy(SEM),Fourier transform infrared spectroscopy(FTIR)and X-ray photoelectron spectroscopy(XPS).SEM indicated that collagen with about 3.07μm thickness was coated on PET surface when the concentration of collagen solution was 1.0 mg/m *** and XPS showed AAc and collagen were both on the surface of PET *** optimized concentration of collagen solution was 1.0 mg/m L,resulting in the most grafting density of 3.46μg/cm^(2).It can be concluded that a large amount of collagen is coated on PET surface.

关键词： collagen acrylic acid(AAc) polycethylene terephthalate(PET) grafting density implantable artificial hair