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Influence of Catalyst Residues on Thermo-oxidative Aging and Thermal Stability of Poly(butene-1)

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Chinese Journal of Polymer Science 2014年第5期32卷 633-639页

作者： Bao-yu Sun Lei Cui Xiu-bo Jiang Bai-yu Jiang 姚薇贺爱华 Key laboratory of Rubber-plastics Ministry of Education/Shandong Provincial Key Laboratory of Rubber-Plastics School of Polymer Science and Engineering Qingdao University of Science and Technology

Isotactic poly（butene-1）（iPB） with spherical morphology was synthesized successfully with bulk precipitation polymerization without post-treatment of the products. The bulk precipitation polymerization process made it possible for iPB to be used as general plastic due to the acceptable decreased cost compared with the solution polymerization process. The influence of catalyst residues on the aging and thermal stability of iPB synthesized by bulk precipitation polymerization method was investigated by gel permeation chromatography, mechanical performance testing, thermogravimetric analysis and infrared spectroscopic analysis. Commercial iPB and the lab-made iPB with varied catalyst residue contents were studied. The results demonstrated that the catalyst residues played an important role in the aging process of the iPB. A possible mechanism of aging promotion by catalyst residues was proposed.

关键词： Catalyst residues Poly(butene-1) Aging Thermal stability.

PREPARATION AND CHARACTERIZATION OF SPHERICAL PP/PB ALLOYS WITH MgCl_2-SUPPORTED ZIEGLER-NATTA CATALYST

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Chinese Journal of Polymer Science 2012年第5期30卷 632-641页

作者：贺爱华 Yang-wei Shi Guo-qing Liu Wei Yao Bao-chen Huang Key laboratory of Rubber-plastics Ministry of Education/Shandong Provincial Key Laboratory of Rubber-PlasticsSchool of Polymer Science and EngineeringQingdao University of Science and Technology

Polypropylene （PP）/polybutene-1 （PB） alloys within reactor were prepared by MgCl2-supported Ziegler-Natta catalyst with sequential two-stage polymerization technology. First, propylene homo-polymerizations were carried out to form isotactic polypropylene （iPP） particles containing active catalyst. Then, butene-1 was subsequently polymerized to form polybutene-1 phase inside the iPP particles. Finally, iPP/PB alloys with spherical shape and adjustable PB content were synthesized. The catalytic activity and catalytic stereospecificity of the Z-N catalyst in the two-stage polymerization process are discussed. The composition and physical properties of the PP alloys were characterized by FT-IR, 13C-NMR, SEM, DSC and XRD. It was found that the in-reactor PP alloys are mainly composed of PP and PB with a little amount of poly（butene- co-propylene） random copolymers and poly（butene-block-propylene） block copolymers. SEM measurements verified that the PB phases with size in the range of 300-400 nm dispersed in the PP matrix uniformly. The incorporation of PB upon the PP matrix affects the properties of final products greatly.

关键词： Polymer blends and alloys Polymer synthesis Polypropylene In situ polymerization.

Synthesis and Characterization of Trans-1,4-butadiene/Isoprene Copolymers: Determination of Sequence Distribution and Thermal Properties

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Chinese Journal of Polymer Science 2015年第6期33卷 815-822页

作者： Xiu-bo Jiang Qing-fei Zhang 贺爱华 Key laboratory of Rubber-plastics Ministry of Education/Shandong Provincial Key Laboratory of Rubber-PlasticsSchool of Polymer Science and EngineeringQingdao University of Science and Technology

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.

关键词： Trans-1,4- Isoprene Butadiene Copolymer Thermal properties.

Dinuclear Nickel(Ⅱ) Chlorides Bearing N,N′-bis(5,6,7-trihydroquinolin-8-ylidene)-[1,1′-biphenyl]-4,4′-diamines: Synthesis and Ethylene Polymerization

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Chinese Journal of Polymer Science 2018年第2期36卷 207-213页

作者： Yan-Ning Zeng Qi-Feng Xing Yan-Ping Ma Wen-Hua Sun laboratory of engineering plastics Beijing National Laboratory for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences

5,6,7-Trihydroquinolin-8-one was condensed with the corresponding benzidine to give N,N′-bis（5,6,7-trihydroquinolin-8-ylidene）-[1,1′-biphenyl]-4,4′-diamine derivatives（L1–L3）. The ligands were reacted with two equivalents of Ni Cl2·6H2O in a mixture of Et OH and CH2Cl2 to afford the corresponding dinickel（II） chloride complexes（Ni1-Ni3）. The organic compounds were completely characterized, whilst the bi-metallic complexes were characterized by FTIR spectra and elemental analysis. These nickel complexes exhibited high activities towards ethylene polymerization in the presence of either MAO or Me2AlCl, maintaining a high activity over a prolonged period. The obtained polyethylenes were confirmed as having low molecular weights by GPC analysis.

关键词： Dinuclear nickel complexes Ethylene polymerization Molecular weight Molecular weight distribution

Synthesis and Characterization of trans-1,4-Butadiene/Isoprene Copolymers: Determination of Monomer Reactivity Ratios and Temperature Dependence

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Chinese Journal of Polymer Science 2014年第8期32卷 1068-1076页

作者： Qing-fei Zhang Xiu-bo Jiang 贺爱华 Key laboratory of Rubber-plastics (Ministry of Education)/Shandong Provincial Key Laboratory of Rubber-PlasticsSchool of Polymer Science and Engineering Qingdao University of Science and Technology

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.

关键词： trans-1,4- Isoprene Butadiene Copolymer Reactivity ratio.

PROSPECTS AND CRUCIAL PROBLEMS IN OLIGOMERIZATION AND POLYMERIZATION WITH IRON AND COBALT COMPLEX CATALYSTS

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Chinese Journal of Polymer Science 2010年第3期28卷 299-304页

作者：孙文华 Key laboratory of engineering plastics and Beijing National laboratory for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences

The discovery of highly active 2,6-bis（imino）pyridyl iron and cobalt complexes provided a milestone of latetransition metal catalysts for ethylene oligomerization and polymerization with being currently investigated for the scale-up process. The crucial problems are remaining in the catalytic systems： the catalytic systems targeting ethylene polymerization produce more oligomers at elevated reaction temperatures, however, there is a recognizable amount of high-molecularweight polyethylene remained in the modified catalytic system for the oligomerization process. Beyond the modification of bis（imino）pyridyl metal complexes, several alternative proeatalysts＇ models have been developed in our group. This review highlighted the achievements in exploring new iron and cobalt complexes with tridentate NNN ligands as procatalysts for ethylene oligomerization and polymerization.

关键词： Iron complex Cobalt complex Ethylene oligomerization Ethylene polymerization

ANNEALING INDUCED VARIATION OF CRYSTALLINE STRUCTURE AND MECHANICAL PROPERTIES OF SYNDIOTACTIC POLYPROPYLENE FIBERS

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Chinese Journal of Polymer Science 2010年第3期28卷 377-384页

作者：王笃金 Beijing National laboratory for Molecular Sciences Key Laboratory of Engineering PlasticsInstitute of Chemistry Chinese Academy of Sciences

Syndiotactic polypropylene （sPP） as-spun fiber （sPP1） and drawn fiber （sPP2） were prepared by melt-spinning and melt-spinning/hot-drawing, respectively. The structure transition of the two fibers induced by annealing at different temperatures and the corresponding mechanical properties were subsequently investigated by the combination of Fourier transform infrared spectroscopy （FTIR）, wide-angle X-ray diffraction （WAXD） and tensile testing. The results indicate that the chain conformation and crystal forms of the two sPP fibers are not obviously changed at low annealing temperature （40℃）. With increasing the annealing temperature, the trans-planar conformation and mesophase in sPP1 and sPP2 fibers can be completely transformed to helical conformation and crystal form I under tension. Upon removing the tension, a small amount of mesophase and trans-planar conformation will be regained. The mechanical properties of the annealed fibers are manifestly dependent on their initial structure and the annealing temperature.

关键词： Syndiotactic polypropylene fiber Annealing treatment Crystal form transition Mechanical properties

STUDIES ON THE MECHANICAL PROPERTIES AND CRYSTALLIZATION BEHAVIOR OF POLYETHYLENE COMPOSITES

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Chinese Journal of Polymer Science 1995年第3期13卷 218-227页

作者：朱进欧玉春冯宇鹏 State Key laboratory of engineering plastics Institute of Chemistry Academia SinicaBeijing 100080

The effects of interfacial modifier on the mechanical, dynamic mechanical properties and crystallization behavior of the polyethylene composites were investigated in the present paper. It was found that the interfacial modifer significantly improved the mechanical properties, influenced the dynamic mechanical spectra and slightly changed the crystallization behavior. The results showed that the interfacial modifier changed the dispersion state of dispersed phase of the composites, resulting in different phase structure, which was the major reason leading to different mechanical and crystallization properties.

关键词： HDPE INTERFACIAL MODIFIER MECHANICAL PROPERTY CRYSTALLIZATION BEHAVIOR

RHEOLOGICAL BEHAVIOR OF KAOLIN TOUGHENED POLYPROPYLENE COMPOSITES

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Chinese Journal of Polymer Science 1997年第1期15卷 8-14页

作者：欧玉春方晓萍冯宇鹏 State Key laboratory of engineering plastics Institute of Chemistry Academia Sinica Beijing 100080

The relation between the rheological behavior and various interfacial properties of Kaolin rigid particle toughened polypropylene(PP/Kaolin) composites were studied by means of parallel-plate rheometer, melt flow rate apparatus, scanning electron microscopy (SEM) and other testing methods. The results show that addition of interfacial modifier to PP/Kaolin composites is advantageous to homogeneous dispersion of filler in PP matrix, formation of flexible interlayer between Kaolin particles and PP matrix and improvement of the melt processibility of the composites.

关键词： modifier filled polypropylene processing rheology