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RING-OPENING POLYMERIZATION OFε-CAPROLACTONE USING LANTHANIDE TRIS(N-PHENYL-3,5-DI-T-BUTYLSALICYLALDIMINATO)S AS SINGLE COMPONENT CATALYST

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Chinese Journal of Polymer Science 2007年第5期25卷 541-544页

作者：沈之荃 Institute of Polymer Science Key laboratory of Macromolecule synthesis and Functionalization Ministry of EducationZhejiang University

Ring-opening polymerization of ε-caprolactone has been carried out by using rare earth Schiff base complexes： lanthanide tris（N-phenyl-3,5-di-t-butylsalicylaldiminato）s [Ln（OPBS）3] as single component catalyst for the first time. The influences of different rare earth elements, monomer and catalyst concentration as well as reaction time on the polymerization were investigated. Mechanism studies showed that monomer inserts into the active site with the acyl-oxygen bond scission rather than the break of alkyl-oxygen bond.

关键词： Ring-opening polymerization ε-Caprolactone Lanthanide Schiff base complex.

THERMAL DECOMPOSITION AND FLAMMABILITY OF ACRYLONITRILEBUTADIENE-STYRENE/MULTI-WALLED CARBON NANOTUBES COMPOSITES

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Chinese Journal of Polymer Science 2008年第3期26卷 331-339页

作者：方征平 Institute of Polymer Composites Key Laboratory of Macromolecular Synthesis and FunctionalizationZhejiang UniversityHangzhou 310027China

Thermal and flammability properties of acrylonitrile-butadiene-styrene copolymer (ABS) with the addition of multi-walled carbon nanotubes (MWNTs) were ***/MWNTs composites were prepared via melt blending with the MWNTs content varied from 0.2% to 4.0% by *** results showed that the addition of MWNTs accelerated the degradation of ABS during the whole process under air atmosphere,and both onset and maximum degradation temperature were lower than those of pure *** destabilization...

关键词： Carbon nanotubes Thermoplastic resin Flammability Thermal properties

INFLUENCE OF LANTHANUM STEARATE AND CALCIUM/ZINC STABILIZERS ON STABILIZATION EFFICIENCY OF DIBUTYLTIN DILAURATE TO POLYVINYL CHLORIDE

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Chinese Journal of Polymer Science 2010年第4期28卷 637-645页

作者：郑强 Department of Polymer Science and Engineering Zhejiang UniversityKey Laboratory of Macromolecular Synthesis and Functionalization of Ministry of Education

Influences of lanthanum stearate （LaSt3） and calcium stearate/zinc stearate （Ca/Zn） stabilizers on stabilization efficiency of dibutyltin dilaurate （DBTDL） to polyvinyl chloride （PVC） in air were investigated. The results revealed that the stabilization effect of DBTDL could be achieved by the La/Sn stabilizers with a ratio of 8/2. Addition of DBTDL could enhance thermal property and reduce dynamic storage modulus （G＇） at 180℃ for PVC containing LaSt3 or Ca/Zn stabilizers. On the other hand, incorporation of LaSh did not influence the stabilization efficiency of DBTDL markedly; while addition of Ca/Zn stabilizers could significantly decrease thermal property for the DBTDL stabilized PVC. Furthermore, the effects of LaSt3 and Ca/Zn stabilizers on the stabilization efficiency of DBTDL were explained in the framework of ionization potential.

关键词： Polyvinyl chloride (PVC) Calcium/zinc stabilizers Lanthanum stearate Dibutyltin dilaurate Ionization potential.

Recent Progress on COS-derived Polymers

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Chinese Journal of Polymer Science 2019年第10期37卷 951-958,I0002页

作者： Cheng-Jian Zhang Xing-Hong Zhang Key laboratory of Macromolecular synthesis and Functionalization (Ministry of Education) Department of Polymer Science & Engineering Zhejiang University

The synthesis of sulfur-containing polymer, a very promising functional material, has made a great progress in the past several years. This review is focused on the very recent advances in poly(monothiocarbonate)s derived from carbonyl sulfide(COS) and epoxides including biomass-derived epoxides. Of significance, metal-free catalyst systems, including triethyl borane/Lewis base pair and thiourea/Lewis base pair are developed for the alternating copolymerization of COS with epoxides. Thereof, the thiourea/Lewis base pair is highly active to the copolymerization of COS with epoxide in a living manner. Moreover, a series of crystalline poly(monothiocarbonate)s are presented, including the copolymers derived from COS with oxetane, ethylene oxide, enantiopure epichlorohydrin, and achiral mesoepoxides via enantioselective copolymerization. Based on these COS/epoxide copolymerization process, a variety of COS-based block copolymers with well-defined structure are presented.

关键词： Carbonyl sulfide Epoxide Copolymerization Poly(monothiocarbonate)

The water-soluble bicyclic 2-pyridone-based fluorescent probe for fast and selective detection of hypochlorite

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Chinese Chemical Letters 2023年第6期34卷 432-436页

作者： Qian Zhou Shanqiang Wang Xiaoyun Ran Linzhi Shen Xiaolin Luo Gui Wang Hui Yang Zhouyu Wang Xiaoqi Yu asymmetric synthesis and Chiral Technology Key laboratory of Sichuan Province Research and Application of Small Organic Chiral Molecules Key Laboratory of Yibin CityDepartment of ChemistryXihua UniversityChengdu 610039China School of Food and Bioengineering Xihua UniversityChengdu 610039China Key laboratory of Green Chemistry and Technology Ministry of EducationCollege of ChemistrySichuan UniversityChengdu 610064China

As a strong oxidizer,hypochlorite(Cl O^(-))are widely employed as bleaching agents and *** of ClO^(-)is required to ensure bactericidal effects and avoid hazards caused by excessive residual ***,the derivative bicyclic 2-pyridone,namely DHIP-Py,was prepared successfully to establish a new ClO^(-)-quantitative *** probe exhibits excellent Cl O^(-)selectivity over other ROS and anions/cations,high sensitivity(LOD=1.32μmol/L),fast response(<5 s),and wide-p H tolerance(pH4~10).Benefit from its good water solubility,DHIP-Py is well suited for water sample analysis and has been successfully applied to detect Cl O^(-)in real-world food and environmental samples,including tap water,bottled water and river *** detection results were essentially identical to that of obtained from traditional DPD ***,visual detection of Cl O^(-)via filter paper-based solid sensor and imaging of ClO^(-)in Escherichia coli were also achieved by *** satisfactory results demonstrate that this bicyclic 2-pyridone-based hypochlorite probe is a promising free chlorine chemosensor with great potential for analytical applications.

关键词： Fluorescent probe Hypochlorite Bicyclic 2-pyridone Tap water Bioimaging

STUDY ON HIGH WELD STRENGTH OF IMPACT PROPYLENE COPOLYMER/HIGH DENSITY POLYETHYLENE LAMINATES

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Chinese Journal of Polymer Science 2011年第4期29卷 497-505页

作者：上官勇刚郑强 Key laboratory of Macromolecular synthesis and Functionalization Ministry of Education Department of Polymer Science and Engineering Zhejiang University

The impact propylene copolymer （IPC） and isotactic polypropylene （iPP） were separately selected to prepare laminates with high density polyethylene （HDPE） by hot press. The peel forces of IPC/HDPE and iPP/HDPE laminates were examined, and it was found that the welded joint strength in IPC/HDPE laminate was dramatically higher than that of iPP/HDPE laminate. According to the special microstructure of IPC, the co-crystallization of the ethylene segments in ethylene-propylene block copolymer （EbP） component of IPC and the PE chain in HDPE was proposed to explain the high- strength welding. The DSC results indicated that there indeed existed some interaction between IPC and HDPE, and the crystallizable PE component in IPC could affect the crystallization of HDPE. The scanning electron microscope （SEM） observations of IPC/HDPE blends demonstrated that HDPE tended to stay with the PE-rich EbP chains to form the dispersed phase, indicating the good miscibility between HDPE and EbP components of IPC. According to the above results, the effect of co-crystallization of the PE components of the IPC and HDPE on the high weld strength of IPC/HDPE laminate was confirmed.

关键词： Impact propylene copolymer Polyethylene Cocrystallization High weld strength.

Effect of Nanoclay on the Phase Separation Behavior of Poly(methyl methacrylate)/Poly(vinyl acetate) Binary Polymer Blends

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Chinese Journal of Polymer Science 2014年第11期32卷 1419-1419,1420-1430页

作者： Ji-shi Zhao 左敏 Chao-ying Lin Qiang Zheng Key laboratory of Macromolecule synthesis and Functionalization Ministry of EducationDepartment of Polymer Science and EngineeringZhejiang University

The effect of nanoclay on the phase-separation behavior of poly（methyl methacrylate）/poly（vinyl acetate）（PMMA/PVAc） blends has been mainly investigated by small-angle laser light scattering. It is found that the effect of clay on the thermodynamics and kinetics of phase-separation for PMMA/PVAc blends seems inconsistent. The kinetics phaseseparation rate decreases, while the thermodynamics parameters, cloud points Tc and delay time tD of isothermal phaseseparation also decrease, and the variation amplitude depends on the matrix composition. The affinity of clay to PMMA results in the composition difference between the border layer and the polymer matrix and further causes the concentration fluctuation at the early stage of phase separation to reduce Tc and tD. On the other hand, the decrease of phase-separation rate is caused by the mechanical barrier effect of clay on the macromolecular diffusion of blend matrix. Hence, such seemingly counterintuitive results on the thermodynamics and kinetics of phase-separation are attributed to different dominant factors.

关键词： Nanocomposites PMMA/PVAc blend Clay Phase separation behavior Morphology.

PREPARATION OF HIGH DENSITY POLYETHYLENE/POLYETHYLENE-BLOCK-POLY(ETHYLENE GLYCOL)COPOLYMER BLEND POROUS MEMBRANES VIA THERMALLY INDUCED PHASE SEPARATION PROCESS AND THEIR PROPERTIES

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Chinese Journal of Polymer Science 2010年第3期28卷 337-346页

作者：朱宝库 Department of Polymer Science and Engineering Key Laboratory of Macromolecule Synthesis and Functionalization(Ministry of Education)Zhejiang University

High density polyethylene （HDPE）/polyethylene-block-poly（ethylene glycol）（PE-b-PEG） blend porous membranes were prepared via thermally induced phase separation （TIPS） process using diphenyl ether （DPE） as diluent. The phase diagrams of HDPE/PE-b-PEG/DPE systems were determined by optical microscopy and differential scanning calorimetry （DSC）. By varying the content of PE-b-PEG, the effects of PE-b-PEG copolymer on morphology and crystalline structure of membranes were studied by scanning electron microscopy （SEM） and wide angle X-ray diffraction （WAXD）. The chemical compositions of whole membranes and surface layers were characterized by elementary analysis, Fourier transform infrared spectroscopy-attenuated total reflection （FTIR-ATR） and X-ray photoelectron spectroscopy （XPS）. Water contact angle, static protein adsorption and water flux experiments were used to evaluate the hydrophilicity, antifouling and water permeation properties of the membranes. It was found that the addition of PE-b-PEG increased the pore size of the obtained blend membranes. In the investigated range of PE-b-PEG content, the PEG blocks could not aggregate into obviously separated domains in membrane matrix. More importantly, PE-b-PEG could not only be retained stably in the membrane matrix during membrane formation, but also enrich at the membrane surface layer. Such stability and surface enrichment of PE-b-PEG endowed the blend membranes with improved hydrophilicity, protein absorption resistance and water permeation properties, which would be substantially beneficial to HDPE membranes for water treatment application.

关键词： High density polyethylene Polyethylene-block-poly(ethylene glycol) copolymer Blend porous membrane Thermally induced phase separation.

L-Lactide Homopolymerization and Copolymerization with ε-Caprolactone by Tetrahydrosalen Stabilized Yttrium Borohydride Complex

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Chinese Journal of Polymer Science 2014年第11期32卷 1500-1506页

作者： Yan-hua Wang Dong Xiang Rong Ren Jin Luo 孙维林 Zhi-quan Shen Key laboratory of Macromolecule synthesis and Functionalization Ministry of Education Department of Polymer Science and EngineeringZhejiang University

L-lactide（LLA） homopolymerization and copolymerization with ε-caprolactone（CL） in toluene initiated by tetrahydrosalen-supported yttrium borohydride complex were systematically investigated. A possible mechanism of LLA homopolymerization was proposed according to the 1H-NMR result. In addition, PCL-b-PLLA copolymers were synthesized by sequential addition of monomers and their structure was characterized by GPC, 1H-NMR and 13C-NMR.

关键词： Yttrium borohydride complex Homopolymerization Block copolymer.