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Bioengineering functional copolymers. XII. Interaction of boron-containing and PEO branched derivatives of poly(MA-alt-MVE) with HeLa cells 被引量:1
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作者 Mustafa Türk Zakir M. O. Rzayev Gülcihan Kurucu 《Health》 2010年第1期51-61,共11页
Novel boron-containing bioengineering copoly- mer and its α-hydoxy-ω-methoxy-poly(ethy- lene oxide (PEO) macrobranched derivatives were synthesized by (1) partially amidolysis of poly(maleic anhydride-alt-methyl vin... Novel boron-containing bioengineering copoly- mer and its α-hydoxy-ω-methoxy-poly(ethy- lene oxide (PEO) macrobranched derivatives were synthesized by (1) partially amidolysis of poly(maleic anhydride-alt-methyl vinyl ether) w?th ethanolamine ester of diphenylboronic acid and (2) esterification of synthesized B-con- taining copolymers with PEO. They had a com- bination of hydrophilic/hydrophobic linkages, free carboxylic groups, positive charges and an ionized organoboron linkage as antitumor sites, along with an ability to interact with HeLa cells. The structure, composition and properties (cy- totoxicity and antitumor activity) of synthe- sized copolymers were investigated. In vitro cytotoxicity results, obtained by the fluore scence microscopy measurements indicate that unlike the virgin copolymer, boron-containing and PEO macrobranched derivatives exhibit higher antitumor activity. It was found that organoboron copolymer exhibits the most apo- ptotic and necrotic effects against HeLa cells whereas a minor effect relative to cancer cells was observed on L929 Fibroblast cells. 展开更多
关键词 Synthesis ORGANOBORON copolymers STRUCTURE-PROPERTY Relations Cytotoxicity ANTITUMOR Activity APOPTOTIC Effect
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Boron-containing copolymers as environmentally friendly lubricant additives
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作者 Hua Xue Fengchun Liang +4 位作者 Weili Yang Qun He Meirong Cai Feng Zhou Weifeng Bu 《日用化学工业(中英文)》 北大核心 2025年第1期1-11,共11页
Increasing environmental concerns about limiting harmful emissions has necessitated sulfur-and phosphorus-free green lubricant additives.Although boron-containing compounds have been widely investigated as green lubri... Increasing environmental concerns about limiting harmful emissions has necessitated sulfur-and phosphorus-free green lubricant additives.Although boron-containing compounds have been widely investigated as green lubricant additives,their macromolecular analogs have been rarely considered yet to develop environmentally friendly lubricant additives.In this work,a series of boron-containing copolymers have been synthesized by free-radical copolymerization of stearyl methacrylate and isopropenyl boronic acid pinacol ester with different feeding ratios(S_(n)-r-B_(m),n=1,m=1/3,1,2,3,5,9).The resulting copolymers of S_(n)-r-B_(m)(n=1,m=1/3,1,2,3,5)are readily dispersed in the PAO-10 base oil and form micelle-like aggregates with hydrodynamic diameters ranging from 9.7 to 52 nm.SRV-IV oscillating reciprocating tribological tests on ball-on-flat steel pairs show that compared with the base oil of PAO-10,the friction coefficients and wear volumes of the base oil solutions of S_(n)-r-B_(m)decrease considerably up to 62%and 97%,respectively.Moreover,the base oil solution of S_(1)-r-B_(1)exhibits an excellent load-bearing capacity of(850±100)N.These superior lubricating properties are due to the formation of protective tribofilms comprising S_(n)-r-B_(m),boron oxide,and iron oxide compounds on the lubricated steel surface.Therefore,the boron-containing copolymers can be regarded as a novel class of environmentally friendly lubricating oil macroadditives for efficient friction and wear reduction without sulfur and phosphorus elements. 展开更多
关键词 friction and wear reduction lubricant additives boron-containing copolymers POLYMERIZATION
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Achieving Complete Photonic Band Gaps in a Low-symmetric Rectangular Cross-sectional Columnar Phase Self-assembled from Block Copolymers
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作者 Hai-Yan Weng Zhan-Wei Li +1 位作者 Yan-Chun Li Zhong-Yuan Lu 《Chinese Journal of Polymer Science》 2025年第6期1059-1066,I0013,共9页
A significant challenge in developing block copolymer photonic crystals is constructing low-symmetric ordered phases,which are essential for achieving a complete photonic band gap.Here,we propose a promising strategy ... A significant challenge in developing block copolymer photonic crystals is constructing low-symmetric ordered phases,which are essential for achieving a complete photonic band gap.Here,we propose a promising strategy to create low-symmetric ordered morphologies by incorporating shape-anisotropic rod-like side chains into block copolymers.Using dissipative particle dynamics simulations,we demonstrate that block copolymers with longer rod-like side chains can self-assemble into a hexagonally packed columnar phase characterized by a low-symmetric rectangular cross-section.Photonic band structure calculations reveal that this low-symmetric columnar phase can exhibit a complete photonic band gap,with the gap size dependent on the aspect ratio of the rectangular cross-sections of the columns.Our findings suggest an effective approach to constructing low-symmetric photonic crystals through the self-assembly of block copolymers with shape-anisotropic segments. 展开更多
关键词 Photonic band gaps Low-symmetric phase SELF-ASSEMBLY Block copolymers
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Optimization of Linear Sequence-controlled Copolymers for Maximizing Adsorption Capacity
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作者 Sheng-Da Zhao Qiu-Ju Chen +2 位作者 Zhi-Xin Liu Quan-Xiao Dong Xing-Hua Zhang 《Chinese Journal of Polymer Science》 2025年第10期1739-1748,共10页
The optimization of polymer structures aims to determine an optimal sequence or topology that achieves a given target property or structural performance.This inverse design problem involves searching within a vast com... The optimization of polymer structures aims to determine an optimal sequence or topology that achieves a given target property or structural performance.This inverse design problem involves searching within a vast combinatorial phase space defined by components,se-quences,and topologies,and is often computationally intractable due to its NP-hard nature.At the core of this challenge lies the need to evalu-ate complex correlations among structural variables,a classical problem in both statistical physics and combinatorial optimization.To address this,we adopt a mean-field approach that decouples direct variable-variable interactions into effective interactions between each variable and an auxiliary field.The simulated bifurcation(SB)algorithm is employed as a mean-field-based optimization framework.It constructs a Hamiltonian dynamical system by introducing generalized momentum fields,enabling efficient decoupling and dynamic evolution of strongly coupled struc-tural variables.Using the sequence optimization of a linear copolymer adsorbing on a solid surface as a case study,we demonstrate the applica-bility of the SB algorithm to high-dimensional,non-differentiable combinatorial optimization problems.Our results show that SB can efficiently discover polymer sequences with excellent adsorption performance within a reasonable computational time.Furthermore,it exhibits robust con-vergence and high parallel scalability across large design spaces.The approach developed in this work offers a new computational pathway for polymer structure optimization.It also lays a theoretical foundation for future extensions to topological design problems,such as optimizing the number and placement of side chains,as well as the co-optimization of sequence and topology. 展开更多
关键词 Combinatorial optimization Optimal design Sequence design COPOLYMER Adsorption problem
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Interfacial Frustration-induced Novel Self-assembled Structures from Block Copolymers under Janus Spherical Confinement
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作者 Xing-Ye Li Zheng Wang +2 位作者 Yu-Hua Yin Run Jiang Bao-Hui Li 《Chinese Journal of Polymer Science》 2025年第8期1423-1432,共10页
Spatial confinement of block copolymers can induce frustrations,which can further be utilized to regulate self-assembled structures,thus providing an efficient route for fabricating novel structures.We studied the sel... Spatial confinement of block copolymers can induce frustrations,which can further be utilized to regulate self-assembled structures,thus providing an efficient route for fabricating novel structures.We studied the self-assembly of AB di-block copolymers(di-BCPs)confined in Janus spherical nanocavities using simulations,and explained the structure formation mechanisms.In the case of a strongly selective cavity wall,all the lamella-forming,gyroid-forming,and cylinder-forming di-BCPs can form interfacial frustration-induced Janus concentric perforated lamellar nanoparticles,whose outermost is a Janus spherical shell and the internal is a sphere with concentric perforated lamellar structure.In particular,Janus concentric perforated lamellar nanoparticles with holes distributed only near the equatorial plane were obtained in both lamella-forming and gyroid-forming di-BCPs,directly reflecting the effect of interfacial frustration.The minority-block domain of the cylider-forming di-BCPs may form hemispherical perforated lamellar structures with holes distributed in parallel layers with a specific orientation.For symmetric di-BCPs,both the A and B domains in each nanoparticle are continuous,interchangeable,and have rotational symmetry.While for gyroid-forming and cylinder-forming di-BCPs,only the majority-block domains are continuous in each nanoparticle,and holes in the minority-block domains usually have rotational symmetry.In the case of a weakly selective cavity wall,the inhomogeneity of the cavity wall results in structures having a specific orientation(such as flower-like and branched structures in gyroid-forming and cylinder-forming di-BCPs)and a perforated wetting layer with uniformly distributed holes.The novel nanoparticles obtained may have potential applications in nanotechnology as functional nanostructures or nanoparticles. 展开更多
关键词 Simulated annealing Diblock copolymer SELF-ASSEMBLY 3D confinement Interfacial frustration
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Insight into the Solution Self-Assembly of Amphiphilic Asymmetric Brush Copolymers via Computer Simulations
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作者 Wei-Ting Zeng Wei-Sheng Feng +3 位作者 Xing Zhang Yuan Yao Bin-Bin Xu Shao-Liang Lin 《Chinese Journal of Polymer Science》 2025年第1期132-140,I0010,共10页
Amphiphilic asymmetric brush copolymers(AABCs)possess unique self-assembly behaviors owing to their asymmetric brush architecture and multiple functionalities of multicomponent side chains.However,the synthesis of AAB... Amphiphilic asymmetric brush copolymers(AABCs)possess unique self-assembly behaviors owing to their asymmetric brush architecture and multiple functionalities of multicomponent side chains.However,the synthesis of AABCs presents challenges,which greatly limits the exploration of their self-assembly behaviors.In this work,we employed dissipative particle dynamics(DPD)simulations to investigate the self-assembly behaviors of AABCs in selective solution.By varying the copolymer concentration and structure,we conducted the self-assembly phase diagrams of AABCs,revealing complex morphologies such as channelized micelles with one or more solvophilic channels.Moreover,the number,surface area,and one-dimensional density distribution of the channelized micelles were calculated to demonstrate the internal structure and morphological transformation during the self-assembly process.Our findings indicate that the morphology of the internal solvophilic channels is greatly influenced by the copolymer structure,concentration,and interaction parameters between the different side chains.The simulation results are consistent with available experimental observations,which can offer theoretical insights into the self-assembly of AABCs. 展开更多
关键词 Dissipative particle dynamics Brush copolymer SELF-ASSEMBLY Channelized micelle
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Preparation and Hydrogenation of Dicyclopentadiene-based Cyclic Olefin Copolymers
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作者 Xiang-Han Zhang Xiao-Hui Mao +4 位作者 Huan Gao Shui-Yuan Luo Zhe Ma Li Pan Yue-Sheng Li 《Chinese Journal of Polymer Science》 2025年第9期1527-1536,I0007,共11页
The design of low-cost and high-performance cyclic olefin copolymers remains challenging.Ethylene copolymers with dicyclopentadiene(DCPD)were prepared using Ph_(2)C(Cp)(Flu)ZrCl_(2)(Cat.1),rac-Et(Ind)_(2)ZrCl_(2)(Cat.... The design of low-cost and high-performance cyclic olefin copolymers remains challenging.Ethylene copolymers with dicyclopentadiene(DCPD)were prepared using Ph_(2)C(Cp)(Flu)ZrCl_(2)(Cat.1),rac-Et(Ind)_(2)ZrCl_(2)(Cat.2),Me_(2)C(Cp)(Flu)ZrCl_(2)(Cat.3)andMe_(2)Si(Ind)_(2)ZrCl_(2)(Cat.4)combined with[Ph_(3)C][B(C_(6)F_(5))_(4)]/iBu_(3)Al.Ni(acac)_(2)/iBu_(3)Al was then used to catalyze the hydrogenation of the intracyclic double bonds of ethylene/DCPD copolymers.The results showed that compared to C_(2) symmetric catalysts(Cat.2 and Cat.4),Cs symmetric catalysts(Cat.1 and Cat.3)facilitated the incorporation of copolymers with higher DCPD.1H-and ^(13)C-NMR spectra indicated that ethylene/DCPD copolymerization occurred via enhancement of the norbornene ring.Additionally,measurement of the reactivity ratios provided further confirmation that the copolymers had random sequence distributions.All these samples demonstrated transmittance values above 90%in the visible wavelength range from 400 nm to 800 nm.By changing the fraction of monomers,the glass transition temperature,refractive index,Young's modulus,and tensile strength of the copolymer increased as the incorporation of DCPD increased,whereas the Abbe number and elongation at break decreased.Compared with ethylene/norbornene and ethylene/tetracyclicdodecene copolymers,ethylene/DCPD copolymers,with excellent optical and mechanical properties,are promising materials. 展开更多
关键词 Cyclic olefin copolymers Coordination polymerization Metallocene catalyst
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Precision Microenvironment-Driven Isothermal Annealing for the Self-Assembly of Perpendicular Block Copolymers in High-Resolution Lithography Applications
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作者 Xiaotong Zhao Yuanlang Hou +11 位作者 Hanxiao Lu Sisi Chen Hui Bai Hanzhe Miao Yuanyuan Guan Sibo Fu Meng Su Xiangshun Geng Ming Lei Yi Yang Yanlin Song Tian-Ling Ren 《Chinese Physics Letters》 2025年第11期375-382,共8页
Block copolymer(BCP) nanolithography offers potential beyond traditional photolithographic limits, yet reliably producing low-defect, perpendicular domains remains challenging. We introduce a microenvironmentdriven is... Block copolymer(BCP) nanolithography offers potential beyond traditional photolithographic limits, yet reliably producing low-defect, perpendicular domains remains challenging. We introduce a microenvironmentdriven isothermal annealing method for directed self-assembly of BCP thin films. By annealing films at stable temperature in a quasi-sealed, inert-gas chamber, our approach promotes highly uniform perpendicular lamellar nanopatterns over large areas, effectively mitigating environmental fluctuations and emulating solvent-vapor annealing without solvent exposure. Resulting BCP structures demonstrate enhanced spatial coherence and notably low defect density. Furthermore, we successfully transfer these nanopatterns into precise metal nano-line arrays,confirming the method's capability for high-fidelity pattern replication. This scalable, solvent-free technique provides a robust, reliable route for high-resolution nanopatterning in advanced semiconductor manufacturing. 展开更多
关键词 photolithographic limits isothermal annealing method mitigating environmental fluctuations e block copolymer bcp annealing films high resolution lithography isothermal annealing microenvironment driven
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High-performance Flow Chemistry Platform for Scalable Continuous Synthesis of Branched Block Copolymers with Precise Chain Structures
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作者 Bang-Bang Wang Zhuang Zhang +3 位作者 Jing-Tao Wang Li Pan Yue-Sheng Li Dong-Po Song 《Chinese Journal of Polymer Science》 2025年第3期457-467,共11页
Cutting-edge research has primarily focused on flow synthesis of linear block copolymers,lacking the ability for manipulating chain architectures for more extensive applications.Herein,we develop a flow chemistry plat... Cutting-edge research has primarily focused on flow synthesis of linear block copolymers,lacking the ability for manipulating chain architectures for more extensive applications.Herein,we develop a flow chemistry platform for the continuous microflow synthesis of bottlebrush block copolymers(BBCPs)using a grafting-through method.This involves performing ring-opening metathesis polymerization(ROMP)of two different macromonomers within two microfluidic reactors connected in series.The microflow environment allows for complete monomer conversion within a few tens of seconds,benefiting from the superior mixing efficiency achieved in Z-shaped channels as indicated by both theoretical simulations and experimental results.Consequently,a library of well-defined BBCPs of up to 528 distinct samples can be produced within one day through automation of the continuous procedure,while keeping precise control on degree of polymerization(DP<4)and polydispersity indices(PDI<1.2).The synthetic method is generally applicable to different macromonomers with different compositions and contour lengths,yielding libraries of branched block copolymers with great diversity in physiochemical properties and chain architectures.This work presents a powerful platform for high-throughput production of branched copolymers,significantly lowering the costs of the materials for real applications. 展开更多
关键词 Continuous flow synthesis Ring opening metathesis polymerization Branched copolymer
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Degradation of PBS-Based Copolymers and Impacts on the Growth of Winter Wheat 被引量:1
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作者 张敏 邢永雷 +2 位作者 苏康宇 马永清 宋吉青 《Agricultural Science & Technology》 CAS 2011年第9期1362-1366,1387,共6页
[Objective] The degradation properties of PBS-based copolymers and impacts on the growth of winter wheat were studied.[Method] Seeds of winter wheat were sown and cultivated in soil,and mixed with equal amounts of PBS... [Objective] The degradation properties of PBS-based copolymers and impacts on the growth of winter wheat were studied.[Method] Seeds of winter wheat were sown and cultivated in soil,and mixed with equal amounts of PBS,PBS-co-HS and PBS-co-BA,to investigate the degradation of polymers in soil and effects of the degradation intermediates and degradation products on seed germination and the growth of winter wheat during the continuous process of degradation.[Result] The results showed that the copolymers had better biodegradation properties than PBS in Lou Soil in Shaanxi Province under the same condition;polymer treatments had not affected the germination percentage and plant height of the winter wheat but contributed to the improvement of plant biomass.[Conclusion] These results suggested that the degradation and degradation products of PBS,PBS-co-HS and PBS-co-BA had not affected the growth of plants in soil environment for temporary. 展开更多
关键词 Winter wheat DEGRADATION PBS-based copolymer
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AMPHIPHILIC STAR-BLOCK COPOLYMERS BY IODIDE-MEDIATED RADICAL POLYMERIZATION 被引量:1
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作者 Bing-yi Li Yan Shi Zhi-feng Fu Wan-tai Yang Shu-ke Jiao 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2007年第6期609-619,共11页
Amphiphilic star-block copolymers composed of polystyrene and poly(acrylic acid) were synthesized by iodide- mediated radical polymerization. Firstly, free radical polymerization of styrene was carried out with AIBN... Amphiphilic star-block copolymers composed of polystyrene and poly(acrylic acid) were synthesized by iodide- mediated radical polymerization. Firstly, free radical polymerization of styrene was carried out with AIBN as initiator and 1,1,1-trimethyolpropane tri(2-iodoisobutyrate) as chain transfer agent, giving iodine atom ended star-shaped polystyrene with three arm chains, R(polystyrene)3. Secondly, tert-butyl acrylate was polymerization using polystyrene obtained as macro-chain transfer agent, and star-block copolymer, R(polystyrene-b-poly(tert-butyl acrylate))3 with controlled molecular weight was obtained. Finally, amphiphilic star-block copolymer, R(polystyrene-b-poly(acrylic acid))3 was obtained by hydrolysis of R(polystyrene-b-poly(tert-butyl acrylate))3 under acidic condition. 展开更多
关键词 Living radical polymerization Iodide-Mediated radical polymerization Star-block copolymers Amphiphilic copolymers.
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ACYCLIC DIENE METATHESIS POLYMERIZATION OF TAILOR-MADE MONOMERS TOWARDS SEQUENCE-REGULATED VINYL COPOLYMERS 被引量:1
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作者 Zi-long Li Lei Li +1 位作者 Fu-sheng Du 李子臣 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2013年第2期355-362,共8页
Acyclic diene metathesis polymerization (ADMET) enables convenient transfer of sequential information of the designed monomers to the corresponding sequence-regulated copolymers. In this study, two structurally symm... Acyclic diene metathesis polymerization (ADMET) enables convenient transfer of sequential information of the designed monomers to the corresponding sequence-regulated copolymers. In this study, two structurally symmetric monomers, M1 and M2, were synthesized via atom transfer radical addition (ATRA) of diethyl meso-2,5- dibromohexanedioate with 1,5-hexadiene and 1,7-octadiene, respectively. Thus, sequenced segment of VB-EA-EA-VB (VB and EA represent vinyl bromide and ethyl acrylate, respectively) was incorporated into the ADMET diene monomers. ADMET polymerization of these two monomers with Grubbs first generation catalyst (Grubbs-I) was performed in CH2C12 at 40℃ for 5 days under nitrogen purge. Effects of catalyst amount, monomer concentration and methanol precipitation on the Mp and PDI of polymers were investigated by GPC, and the structures of the formed polymers were characterized by NMR. Our results indicate that using 3.0 mol% of Grubbs-I to monomer can afford polymers with high Mp. Moreover, selective precipitation in methanol enables complete removal of low molecular weight components from the crude products. Meanwhile, M2 exhibits higher ADMET polymerization reactivity than M1 due to its capability of suppressing negative neighboring group effect. 展开更多
关键词 ADMET ATRA Sequence-regulated copolymers.
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Nutrient Release Characteristics of Vinyl Chloride-Vinyl acetate Copolymers Coated SlowRelease Nitrogen Fertilizer and Its Effect on Soil Mineral Nitrogen
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作者 马洪波 许仙菊 +3 位作者 宁运旺 汪吉东 张辉 张永春 《Agricultural Science & Technology》 CAS 2014年第3期412-416,421,共6页
[Objective] The aim was to explore release characteristics of vinyl chlo- ride-vinyl acetate copolymer controlled-release N fertilizer and the effects on minerat nitrogen in soils. [Method] Vinyl chloride-vinyl acetat... [Objective] The aim was to explore release characteristics of vinyl chlo- ride-vinyl acetate copolymer controlled-release N fertilizer and the effects on minerat nitrogen in soils. [Method] Vinyl chloride-vinyl acetate copolymer and hydroxyl-modi- fied VCNAc were taken as coating materials to prepare slow release fertilizer. Nutri- ent release characteristics of VC/VAc slow release fertilizer was evaluated by water immersion method and the effects of VC/VAc slow release fertilizer on mineral ni- trogen were researched by pot experiment. [Result] The release periods of VC-VAc controlled-release urea and hydroxyl-modified VC/VAc coated urea were 60 and 50 d, respectively. Furthermore, the content of ammonium nitrogen reached the peak on the 30th d and the content of nitrate nitrogen reached the peak on the 60th d in soils in treatments with VCNAc and hydroxyl-modified VC/VAc; the content of nitrate nitrogen rose again on the 120th d in the treatment with VC/VAc. In terms of wheat yield, different treatments showed insignificant differences and rice yield in the treatment with VCNAc was significantly higher than that in the treatment with hy- droxyl-modified VCNAc (P〈0.05). [Conclusion] The release days of slow controlled- release fertilizer vary upon pot experiment method and water immersion method. Slow controlled-release fertilizer is not suitable for monoculture, due to long fertilizer efficiency, but multiple cropping would be optimal for its role to be fully exploited. 展开更多
关键词 Water immersion method Pot experiment method Vinyl chloride-vinyl acetate copolymer Nutrient release characteristics Soil mineral nitrogen
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Synthesis and Characterization of Trans-1,4-butadiene/Isoprene Copolymers: Determination of Sequence Distribution and Thermal Properties 被引量:11
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作者 Xiu-bo Jiang Qing-fei Zhang 贺爱华 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2015年第6期815-822,共8页
Abstract Two series of trans-1,4-poly(butadiene-co-isoprene) copolymers (TBIR) were prepared using the catalyst system TiCl4/MgCl2-Al(i-Bu)3 at different reaction temperatures. All dyad and triads sequence distr... Abstract Two series of trans-1,4-poly(butadiene-co-isoprene) copolymers (TBIR) were prepared using the catalyst system TiCl4/MgCl2-Al(i-Bu)3 at different reaction temperatures. All dyad and triads sequence distributions, the number-average sequence length and the sequence concentration of the copolymers were calculated according to 13C-NMR spectra. The influences of temperature and initial molar ratio of butadiene to isoprene (Bd to Ip) on the distribution of the chain segments in the TBIR copolymers were discussed. The correlation of copolymer compositions and thermal properties were also evaluated, which facilitated the understanding of controlling the degree of crystallinity and the transition tempera^re by changing Bd content and temperature. 展开更多
关键词 Trans-1 4- ISOPRENE BUTADIENE COPOLYMER Thermal properties.
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Synthesis and Characterization of trans-1,4-Butadiene/Isoprene Copolymers: Determination of Monomer Reactivity Ratios and Temperature Dependence 被引量:9
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作者 Qing-fei Zhang Xiu-bo Jiang 贺爱华 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2014年第8期1068-1076,共9页
A series of trans-1,4-butadiene/isoprene copolymers were prepared using the catalyst system TiCl4/MgCl2-Al(i- Bu)3 with bulk precipitation technology at different temperatures. Monomers reactivity ratios were calcul... A series of trans-1,4-butadiene/isoprene copolymers were prepared using the catalyst system TiCl4/MgCl2-Al(i- Bu)3 with bulk precipitation technology at different temperatures. Monomers reactivity ratios were calculated based on the Kelen-Tiid6s (K-T) method and the Mao-Huglin (M-H) method. The influence of temperature on copolymer composition and polymerization rate was discussed in detail. The increase of reaction temperature brought the decrease of butadiene reactivity ratio rBd and supplied an effective adjustment on copolymers' composition distribution. 展开更多
关键词 trans-1 4- ISOPRENE BUTADIENE COPOLYMER Reactivity ratio.
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SYNTHESIS,SELF-ASSEMBLY AND RESPONSIVE PROPERTIES OF PEG-b-PDMAEMA-b-PMMAzo TRIBLOCK COPOLYMERS 被引量:7
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作者 Yao-hui Xing 林绍梁 +1 位作者 林嘉平 Xiao-hua He 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2013年第5期833-840,共8页
A novel amphiphilic copolymer poly(ethylene glycol)-block-poly(N,N-dimethylamino-2-ethylmethacrylate)-block- poly[6-(4-methoxy-azobenzene-4'-oxy) hexyl methacrylate] (PEG-b-PDMAEMA-b-PMMAzo) was prepared by A... A novel amphiphilic copolymer poly(ethylene glycol)-block-poly(N,N-dimethylamino-2-ethylmethacrylate)-block- poly[6-(4-methoxy-azobenzene-4'-oxy) hexyl methacrylate] (PEG-b-PDMAEMA-b-PMMAzo) was prepared by ATRP polymerization. The self-assembly and responsive behaviors were investigated by SEM, TEM, LLS and UV-Vis spectra. The results indicated that the copolymers can self-assemble into spherical structures in aqueous media. The aggregate size can be tuned by pH and temperature. The trans-cis isomerization behavior of the formed aggregates was also examined. Upon irradiation with a linear polarized light, the elongation degree of the aggregates was increased with the irradiation time. 展开更多
关键词 zobenezene COPOLYMER SELF-ASSEMBLE Responsive.
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DRUG AND PLASMID DNA CO-DELIVERY NANOCARRIERS BASED ON ABC-TYPE POLYPEPTIDE HYBRID MIKTOARM STAR COPOLYMERS 被引量:6
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作者 Tao Liu Yan-feng Zhang 刘世勇 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2013年第6期924-937,共14页
We report on the fabrication of self-assembled micelles from ABC-type miktoarm star polypeptide hybrid copolymers consisting of poly(ethylene oxide), poly(L-lysine), and poly(e-caprolactone) arms, PEO(-b-PLL)-... We report on the fabrication of self-assembled micelles from ABC-type miktoarm star polypeptide hybrid copolymers consisting of poly(ethylene oxide), poly(L-lysine), and poly(e-caprolactone) arms, PEO(-b-PLL)-b-PCL, and their functional applications as co-delivery nanocarriers of chemotherapeutic drugs and plasmid DNA. Miktoarm star copolymer precursors, PEO(-b-PZLL)-b-PCL, were synthesized at first via the combination of consecutive "click" reactions and ring-opening polymerizations (ROP), where PZLL is poly(e-benzyloxycarbonyl-L-lysine). Subsequently, the deprotection of PZLL arm afforded amphiphilic miktoarm star copolymers, PEO(-b-PLL)-b-PCL. In aqueous media at pH 7.4, PEO(-b-PLL)-b-PCL self-assembles into micelles consisting of PCL cores and hydrophilic PEO/PLL hybrid coronas. The hydrophobic micellar cores can effectively encapsulate model hydrophobic anticancer drug, paclitaxel; whereas positively charged PLL arms within mixed micellar corona are capable of forming electrostatic polyplexes with negatively charged plasmid DNA (pDNA) at N/P ratios higher than ca. 2. Thus, PEO(-b-PLL)-b-PCL micelles can act as co-delivery nanovehicles for both chemotherapeutic drugs and genes. Furthermore, polyplexes of pDNA with paclitaxel-loaded PEO(-b- PLL)-b-PCL micelles exhibited improved transfection efficiency compared to that of pDNA/blank micelles. We expect that the reported strategy of varying chain topologies for the fabrication of co-delivery polymeric nanocarriers can be further applied to integrate with other advantageous functions such as targeting, imaging, and diagnostics. 展开更多
关键词 Miktoarm star copolymers Gene delivery CO-DELIVERY POLYPEPTIDE SELF-ASSEMBLY
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ANTIFOULING PROPERTIES OF POLYVINYL CHLORIDE) MEMBRANES MODIFIED BY AMPHIPHILIC COPOLYMERS P(MMA-A-MAA) 被引量:7
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作者 朱宝库 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2012年第4期568-577,共10页
Three well-defined diblock copolymers ofpoly(methyl methacrylate-b-methacrylic acid) (P(MMA-b-MAA)) were synthesized using atom transfer radical polymerization method and varying poly(methacrylic acid) (PMAA... Three well-defined diblock copolymers ofpoly(methyl methacrylate-b-methacrylic acid) (P(MMA-b-MAA)) were synthesized using atom transfer radical polymerization method and varying poly(methacrylic acid) (PMAA) chain lengths. These copolymers were blended with PVC to fabricate porous membranes via phase inversion process. Membrane morphologies were observed by scanning electron microscopy (SEM), and chemical composition changes of the membrane surfaces were measured by X-ray photoelectron spectroscopy (XPS). Static and dynamic protein adsorption experiments were used to evaluate antifouling properties of the blend membranes. It was found that, the blend membranes containing longer PMAA arm length showed lower static protein adsorption, higher water permeation flux and better protein solution flux recovery. 展开更多
关键词 Amphiphilic copolymer ATRP Poly(vinyl chloride) Antifouling property P(MMA-b-MAA).
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Polythiophene-block-poly(phenyl isocyanide) Copolymers: One-pot Synthesis, Properties and Applications 被引量:5
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作者 Li Zhou Zhi-qiang Jiang +2 位作者 Lei Xu 刘娜 吴宗铨 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2017年第12期1447-1447,1448-1456,共10页
Conjugated block copolymers have gained increasing interests in recent years. Development of a novel method for facile synthesis of conjugated block copolymers with desired structures and functions is greatly desired.... Conjugated block copolymers have gained increasing interests in recent years. Development of a novel method for facile synthesis of conjugated block copolymers with desired structures and functions is greatly desired. In this mini review, we summarized the recent advances in one-pot synthesis of conjugated block copolymers containing π-conjugated polythiophene and helical polyisocyanide segments by using a nickel(Ⅱ) complex as single catalyst. The sequential living polymerization of the two monomers proceeded in a controlled manner, affording expected block copolymers in high yields with controlled molecular weights(Mns) and narrow molecular weight distributions(Mw/Mns). By using this method, a family of block copolymers with expected structure and tunable compositions can be facilely prepared. Introducing functional groups onto the pendant, these block copolymers can exhibit interesting self-assembly property, tunable light emission and multi-responsiveness. 展开更多
关键词 Conjugated polymer Helical polymer Polyisocyanide Block copolymer Living polymerization
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Orthogonal Solubility in Fully Conjugated Donor-Acceptor Block Copolymers: Compatibilizers for Polymer/Fullerene Bulk-Heterojunction Solar Cells 被引量:4
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作者 Shi-fan Wang Ya-nan Liu +6 位作者 Jie Yang 陶友田 Yan Guo Xu-dong Cao 张志国 Yong-fang Li 黄维 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2017年第2期207-218,共12页
Donor-acceptor (D-A) type fully conjugated block copolymer systems have been rarely reported due to the challenges in synthetic approaches to prepare well-defined low-polydispersity products. In this work, fully con... Donor-acceptor (D-A) type fully conjugated block copolymer systems have been rarely reported due to the challenges in synthetic approaches to prepare well-defined low-polydispersity products. In this work, fully conjugated block copolymers are synthesized in a one-pot reaction through Stille coupling polycondensation, by utilizing the end-functional polymer copolymerization method. End-functional P3HT are copolymerized with AA (2,7-dihromo-9-(heptadecan-9-yl)-9H- carbazole) and BB (4,7-bis(5-(trimethylstannyl)thiophen-2-yl)benzo[c][1,2,5]thiadiazole, TBT) type monomers, respectively. The orthogonal solubility between the very soluble P3HT donor and the insoluble PCDTBT acceptor block improves the purity of block copolymers as well as distinct nano-scale phase-separation compared with other reports on miscibility of donor and acceptor polymer block. Further purification via preparative GPC is carried out to remove the excess of unreacted P3HT and free PCDTBT as well as to achieve low polydispersity of block copolymers. The chemical structure of the P3HT- b-PCDTBT block copolymers are verified via IH-NMR, and further confirmed by FTIR spectra. The block copolymer shows broad absorption and moderate optical band gap of 1.8 eV. Furthermore, the fully conjugated block copolymer films exhibit significant fine structures, much smoother film morphology compared to P3HT/PCDTBT polymer blends. By adding a small amount of block copolymer P3HT-b-PCDTBT as a compatibilizer into the bulk-heterojunction of P3HT:PC61BM blends, polymer solar ceils with an 8% increase of short circuit current (Jse) and 10% increase of power conversion efficiency (PCE) are achieved owing to the improvement of the active-layer film morphology. To the best of our knowledge, this is the first report on donor-acceptor type fully conjugated block copolymer as an effective ternary additive in polymer: fullerene bulk heterojunction solar cells. 展开更多
关键词 Block copolymers Donor ACCEPTOR Bulk heterojunction solar cells COMPATIBILIZER
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