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MELTING CRYSTALLIZATION BEHAVIOR OF NYLON 66

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chinese Journal of polymer Science 2001年第3期19卷 237-246页

作者： Qing-xin Zhang Zhi-shen Mo State key laboratory of polymer physics & chemistry changchun institute of applied chemistry chinese academy of sciences, changchun 13..22, china chinese Acad Sci Changchun Inst Appl Chem State Key Lab Polymer Phys & Chem Changchun 130022 Peoples R China

Analysis of isothermal and nonisothermal crystallization kinetics of nylon 66 was carried out using differential scanning calorimetry (DSC). The commonly used Avrami equation and that modified by Jeziorny were used, respectively, to fit the primary stage of isothermal and nonisothermal crystallizations of nylon 66. In the isothermal crystallization process, mechanisms of spherulitic nucleation and growth were discussed. The lateral and folding surface free energies determined from the Lauritzen-Hoffman treatment are sigma = 9.77 erg/cm(2) and sigma (e) = 155.48 erg/cm(2), respectively; and the work of chain folding is q = 33.14 kJ/mol. The nonisothermal crystallization kinetics of nylon 66 was analyzed by using the Mo method combined with the Avrami and Ozawa equations. The average Avrami exponent (n) over bar was determined to be 3.45. The activation energies (DeltaE) were determined to be -485.45 kJ/mol and -331.27 kJ/mol, respectively, for the isothermal and nonisothermal crystallization processes by the Arrhenius and the Kissinger methods.

关键词： nylon 66 crystallization kinetics activation energy

Polyfluorenes containing pyrazine units:Synthesis,photophysics and electroluminescence

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Science china chemistry 2011年第4期54卷 656-665页

作者： wang Ming,LI Ying,XIE ZhiYuan & wang LiXiang State key laboratory of polymer physics and chemistry changchun institute of applied chemistry,chinese academy of sciences,changchun 13..22,china 1. State key laboratory of polymer physics and chemistry changchun institute of applied chemistry Chinese Academy of Sciences Changchun 130022 China

A series of conjugated copolymers of 9,9-dioctylfluorene and symmetrical pyrazine unit (BY) were synthesized by Suzuki copolymerization and were used as novel light-emitting materials in *** energy transfer was observed in both thin film and *** with the lowest occupied molecular orbital (LUMO) energy level of the polyfluorenes homopolymer (Pfo),the lower LUMO energy levels of copolymers indicated that the introduction of the BY unit would be benefit to electron *** turn-on voltages of their single-layer electroluminescent (EL) devices (ITO/PEDOT/polymer/LiF/Al) were at 6.1-4.0 V,which were much lower than that of Pfo (7.0 V).The maximum brightness,current efficiency,and external quantum efficiency of all PFBY copolymers were higher than those of the Pfo *** single-layer device of PFBY5 was the best one in the copolymers,with a maximum brightness of 485 cd/m2,a current efficiency of 0.29 cd/A,and an external quantum efficiency of 0.10%.The introduction of PVK and TPBI for the multilayer device of PFBY5 increased the device efficiencies,which showed a maximum brightness of 3012 cd/m2,a maximum current efficiency of 1.81 cd/A,and an external quantum efficiency of 0.66%.

关键词： pyrazine polyfluorenes energy transfer PLED

Monte Carlo simulation on kinetic behavior of one-pot hyperbranched polymerization based on AA*+CB_2

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Science china chemistry 2010年第12期53卷 2481-2489页

作者： ZHAN Jie,LIN Ying,LIU XiaoHui & LI YueSheng State key laboratory of polymer physics and chemistry changchun institute of applied chemistry,chinese academy of sciences,changchun 13..22,china 1. State key laboratory of polymer physics and chemistry changchun institute of applied chemistry Chinese Academy of Sciences Changchun 130022 China

Monte Carlo simulation was applied to investigate the kinetic behavior of AA*+CB2 *** algorithm consisted of two procedures to simulate the in-situ synthesis of AB2-like intermediate and the subsequent polymerization,*** order to improve the accuracy of the prediction,the mobility distinction between different scale molecules in polymerization was taken into account by relating the reaction rate constants to the collision possibility of each pair of *** feed ratio of initial monomers and the activity difference between the two functional groups within AA* were studied systematically to catch the essential features of the *** results have revealed that the achievable maximum conversion primarily depends on the extent of the reactivity difference between A and A*-groups,and it is suggested that A*-group should be at least 10 times more active than A-group to achieve high number-average degree of polymerization.

关键词： Monte Carlo hyperbranched kinetic AA+CB2

KINETICS STUDY ON MELT GRAFTING ACRYLIC ACID ONTO LLDPE USING REACTIVE EXTRUSION

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chinese Journal of polymer Science 2005年第6期23卷 603-610页

作者： Qiang Shi Lian-chao Zhu Chuan-lun Cai and Jing-hua Yin State key laboratory of polymer physics and chemistry,changchun institute of applied chemistry,chinese academy of sciences,changchun 13..22,china chinese Acad Sci Changchun Inst Appl Chem State Key lab Polymer Phys & Chem Changchun 130022 Peoples R China

The kinetics of melt grafting acrylic acid （AA） onto linear low density polyethylene （LLDPE） by using reactive extrusion was investigated. The polymeric peroxides （POOP and POOH） generated by electron beam irradiation were used to initiate the graft reaction. The samples taken out from the barrel at five ports along screw axis were analyzed by FTIR. The spectra show that both the graft copolymerization and homopolymerization proceed in two stages： the graft degree （or mass of homopolymer） increases linearly with the reaction time in the initial stage, and then gradually in the second stage. The rate of graft copolymerization Rg is always faster than that of homopolymerization Rh in the present system and the activation energy is 131 kJ · mol^-1 for graft copolymerization and 127 kJ · mol^-1 for homopolymeirzation. These results were interpreted in terms of solubility and diffusion of monomer, as well as the reactivity and the concentration of reactive species. The relationships between reaction rate and monomer concentration and peroxide concentration were found to be： Rg ∞ [M]^1.46[POOP＋POOH]^0.53 and Rh ∞ [M] ^1.08[POOH]^0.51, which indicate that the addition of monomer to polymeric radicals is a slow step for the graft copolymerization.

关键词： Graft copolymerization Kinetics Reactive extrusion

STUDIES ON THE INTERFACIAL ADHESION BETWEEN FUNCTIONALIZED POLYPROPYLENE AND POLYAMIDE 1010

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chinese Journal of polymer Science 1999年第3期17卷 237-244页

作者： Xiao-min Zhang Zhihui Yin Yongxian song Jinghua Yin polymer physics laboratory, changchun institute of applied chemistry, chinese academy of sciences, changchun 13..22, china chinese Acad Sci Changchun Inst Appl Chem Polymer Phys Lab Changchun 130022 Peoples R China

The interface behavior of polyamide 1010 (PA1010) and polypropylene (PP) was studied. In order to improve their interfacial adhesion, functional PP was prepared by means of grafting glycidyl methacrylate (GMA) on PP main chains and used instead of plain PP. Several technological characterizations were performed here on their interfaces. ESCA was used to confirm that some kind of reaction occurred between end groups of PA1010 and epoxy species of PP-g-GMA. The peel test was adopted to measure interfacial adhesion. It was found that the fracture energy of interfaces between PA1010 and PP-g-GMA was dramatically increased with the content of GMA. Their interfaces were observed as being blurred by using SEM and TEM and a crack that could be seen in the case of the interfaces of the PA1010 and the plain PP disappeared.

关键词： polyamide 1010 polypropylene-g-GMA interface behavior adhesion

BRITTLE-DUCTILE TRANSITION OF polymerS AND ITS PERCOLATION MODEL

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chinese Journal of polymer Science 2003年第2期21卷 129-134页

作者： Wei Jiang Li-jia An Bing-zheng Jiang State key laboratory of polymer physics and chemistry changchun institute of applied chemistry chinese academy of sciences, changchun 13..22, china chinese Acad Sci Changchun Inst Appl Chem State Key Lab Polymer Phys & Chem Changchun 130022 Peoples R China

The brittle-ductile transition (BDT) of particlc toughened polymers was extensively studied in terms ofmorphology, strain rate, and temperature. The calculation results showed that both the critical interparticle distance (ID_c) andthe brittle-ductile transition temperature (T_(BD)) of polymers were a function of strain rate. The ID_c reduced nonlinearly withincreasing strain rate, whereas T_(BD) increased considerably with increasing strain rate. The effects of temperature andplasticizer concentration on BDT were discussed using a percolation model. The results were in agreement with theexperiments.

关键词： Particle toughening polymers Brittle-ductile transition Percolation

SYNTHESIS AND CRYSTALLIZATION BEHAVIOR OF POLY(ETHER ETHER KETONE ETHER KETONE)(PEEKEK)

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chinese Journal of polymer Science 2000年第2期18卷 129-132页

作者： Zhao-bin Qiu Zhi-shen Mo Ying-ning Yu Hong-fang Zhang Xian-hong wang polymer physics laboratory, changchun institute of applied chemistry, chinese academy of sciences, changchun 13..22, china chinese Acad Sci Changchun Inst Appl Chem Polymer Phys Lab Changchun 130022 Peoples R China

In this paper, the synthesis and crystallization behavior of poly(ether ether ketone ether ketone) (PEEKEK) are reported. PEEKEK was prepared from 4,4'-bis(p-fluorobenzoyl) diphenyl ether (4,4'-FBDE) and hydroquinone along the nucleophilic substitution route. The thermal properties were investigated by using DSC and TGA. The crystallization behavior of PEEKEK under several conditions, i.e., crystallization from the molten state (melt crystallization), crystallization from a quenched sample (cold crystallization) and crystallization induced by exposing glassy sample to methylene chloride (solvent-induced crystallization) has also been investigated. The results show that crystallization of PEEKEK could be induced by the above methods, and no polymorphism was found. The differences in the crystallization of PEEKEK induced by the above methods are seen in their degree of crystallinity.

关键词： poly(aryl ether ketone)s synthesis crystallization

Microstructure Characterization of Short-chain Branching Polyethylene with Differential Scanning Calorimetry and Successive Self-nucleation/Annealing Thermal Fractionation

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chinese Journal of polymer Science 2014年第6期32卷 751-757页

作者： Yan-hu Xue Yan-hui wang Yan-di Fan He-ran YangState key laboratory of polymer physics and chemistry changchun institute of applied chemistry chinese academy of sciences Tao Tang Shu-qin Bo 姬相玲 State key laboratory of polymer physics and chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences University of chinese academy of sciences

A series of the copolymers of ethylene with 1-hexene （M1-M9） synthesized by metallocene catalyst Et[Ind]2ZrC1JMAO was studied by differential scanning calorimetry and successive self-nucleation and annealing （SSA） thermal fractionation. The distribution of methylene sequence length （MSL） in the different copolymers was determined using the SSA method. The comonomer contents of samples M4 and M5 are 2.04 mol% and 2.78 mol%, respectively. Both M4 and M5 have low comonomer content and their MSL distribution profiles exhibit a monotonous increase trend with their MSL. The longest MSL of M5 is 167, and its corresponding molar percent is 43.95%, which is higher than that of M4. Moreover, the melting temperature （Tm） of M5 is also higher than that of M4. The comonomer contents of samples M7, M8, and M9 are 8.73 mol%, 14.18 mol% and 15.05 mol%, respectively. M7, M8, and M9 have high comonomer contents, and their MSL distribution profiles display unimodality. M7 has a lower peak value of 33 and a narrow MSL distribution, resulting in a Tm lower than that of M8 and M9. The MSL and its distribution are also key points that influence the melting behavior of copolymers. Sometimes, MSL and its distribution of copolymers have a greater impact on it than the total comonomer contents, which is different from traditional views.

关键词： Polyethylene Methylene sequence length (MSL) Microstructure Successive self-nucleation and annealing(SSA) SCB.

Synthesis of a New Aryl Ether Ketone polymer

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chinese Chemical Letters 1998年第10期9卷 893-894页

作者： Zhao Bin QIU Zhi Shen MO Hong Fang ZHANG (polymer physics laboratory, changchun institute of applied chemistry, chinese academy of sciences, changchun 13..22) Acad Sinica Changchun Inst Appl Chem Polymer Phys Lab Changchun 130022 Peoples R China

The synthesis of a new aryl ether ketone polymer with an advantageous ratio of glass transition temperature to melting temperature is reported.

关键词： poly(aryl ether ketone) synthesis