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Cationic Polymerization of isobutylene and C4 Mixed Feed Using Complexes of Lewis Acids with Ethers: A Comparative Study

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Chinese Journal of Polymer Science 2019年第9期37卷 891-897页

作者： Dmitriy I. Shiman Ivan A. Berezianko Irina V. Vasilenko Sergei V. Kostjuk Research Institute for Physical Chemical Problems of the Belarusian State University 14 Leningrads kaya St. Minsk 220006 Belarus Department of Chemistry Belarusian State University 14 Leningradskaya st. Minsk 220006 Belarus Sechenov First Moscow State Medical University Institute for Regenerative Medicine 8-2 Trubetskaya st. Moscow 119991 Russia

The cationic polymerization of C4 mixed feed and isobutylene co-initiated by AlCl3xOiPr2,iBuAlC12xnOiPr2, and [emim]Cl- FeCl3xnOiPr2 ([emim]Cl: 1 -ethyl-3-methylimidazolium chloride) has been investigated. AlCl3xOiPr2 co-initiated cationic polymerization of C4 mixed feed proceeds at a lower rate than polymerization of isobutylene affording polymers with higher molecular weight. Complexes of iBuAlCh with di isopropyl ether of different compositions are more suitable co-initiators than AlCl3xOiPr2 for the synthesis of highly reactive polyisobutylene (HR PIB) from C4 mixed feed due to their higher activity in the polymerization as well as possibility to prepare polyisobutylenes with lower molecular weight and higher content of exo-olefin end groups. However, iBuA1C12 needs activating via addition of external water (initiator) and/or interaction with salts hydrates in order to increase the reaction rate and the saturated monomer conversion.[Emim]Cl-FeC13/iPr2O is a quite promising catalyst for the preparation of HR PIB with high exo-olefin end group content (> 80%) and relatively low polydispersity (Mw/Mn < 2.8) via cationic polymerization of C4 mixed feed. The sonication of reaction mixture in case of using [emim]Cl-FeCh allowed increasing the reaction rate and decreasing the molecular weight.

关键词： Cationic polymerization isobutylene C4 mixed feed Highly reactive polyisobutylene

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CATIONIC POLYMERIZATION OF isobutylene COINITIATED BY AICI_3 IN THE PRESENCE OF ETHYL BENZOATE

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Chinese Journal of Polymer Science 2010年第1期28卷 55-62页

作者：吴一弦 State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology

The cationic polymerizations of isobutylene （IB） coinitiated by AlCl3 were carried out in solvent mixture of nhexane/methylene dichloride （n-hex/CH2Cl2） of 60/40 V/V in the presence of ethyl benzoate （EB） at various temperatures range from -80℃ to -30℃. The effects of EB concentration （[EB]） and polymerization temperature on monomer conversion, weight-average molecular weight （Mw） and molecular weight distribution （MWD, Mw/Mn） of polyisobutylene （PIB） products were investigated. The rate of polymerization decreased while Mw of PIB products increased with increasing [EB]. The polymers with high molecular weight could be prepared in the presence of a suitable amount of EB. Significantly, the polymers with high Mw of 80.2 × 10^4 and 65.4 × 10^4 could be produced at -80℃ and -70℃ at [EB] = 0.24 × 10^3 mol/L respectively, which were much higher than that （Mw = 57.9 × 10^4） of PIB prepared at -100℃ in the absence ofEB. A simple but effective method for preparing the high molecular weight polyisobutylenes was developed in this work. It has been also found that the activation energy for propagation （Ep） depended on the polymerization temperature range in the presence of EB. An obvious inflection of the linear plots of lnXn versus 1/Tp occurred at the temperature range from -60℃ to -50℃ at four different concentrations of EB from 0.19 × 10^3 mol/L to 0.33× 10^3 tool/L, and thus the inflection temperature （Tinf） was in the range of -60℃ to -50℃. When [EB] was in the range of 0.24 × 10^3 mol/L to 0.33× 10^3 mol/L, Ep was determined to be around -12 kJ/mol when the polymerization was carried out at temperatures from -80℃ to Tinf and to be around -28 kJ/mol at temperatures from Tinf to -15℃ respectively.

关键词： Electron donor Cationic polymerization isobutylene Polyisobutylene.

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Functionalized Copolymers of isobutylene with Vinyl Phenol: Synthesis,Characterization, and Property

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Chinese Journal of Polymer Science 2019年第9期37卷 919-929页

作者： Shi-Xuan Yang Zi-Yu Fan Feng-Yu Zhang Si-Hao Li Yi-Xian Wu State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology

The random copolymers of isobutylene (IB) with polar comonomers of 4-acetoxystyrene (ACS) or 4-tert-butoxystyrene (TBO), P(IB-co-ACS) and P(IB-co-TBO), could be successfully synthesized via cationic copolymerization with FeCh-based initiating system. The kinetics of the cationic copolymerization process was in situ investigated by inserting a diamond probe into the reaction system by ATR-FTIR spectroscopy. The chemical structure and incorporation content of polar comonomers in the copolymers were characterized by GPC with RI/UV dual detectors and 1H-NMR spectroscopy. The corresponding functionalized random copolymers of IB with vinyl phenol P(IB-co-POH) carrying phenolic hydroxyl side groups could be further prepared via the complete hydrolysis of acetoxyl side groups in P(IB-co-ACS) or tert-butoxyl side groups in P(IB-co-TBO) copolymers. The functionalized P(IB-co-POH) copolymers became hydrophilic with water contact angle (WCA) of ca. 80° for the self-assembly in hot water, compared to the hydrophobic polyisobutylene with WCA of ca. 110°. The functionalized P(IB-co-POH) copolymers also displayed an excellent self-healing property due to the interaction of intermolecular hydrogen bonding and formation of three dimentional supramolecular networks from phenolic hydroxyl side groups. Furthermore, P(IB-co-POH) copolymers also provided a good matrix for the homogeneous dispersion for silica nanoparticles due to the formation of hydrogen bonding between copolymer chains and silica nanoparticles.

关键词： Cationic polymerization isobutylene Copolymers Polar monomer Functionalized polyisobutylenes

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Effect of Phosphoric Acid on HZSM-5 Catalysts for Prins Condensation to Isoprene from isobutylene and Formaldehyde

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Chemical Research in Chinese Universities 2018年第3期34卷 485-489页

作者： YU Xue ZHANG Yuewei LIU Bing MA Huiyong WANG Yan BAO Qiang WANG Zhenlu Key Laboratory of Surface and Interface Chemistry of Jilin Province College of Chemistry Jilin University Changchun 130021 P. R. China Jilin Institute of Chemical Technology Jilin 132022 P. R. China State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of Chemistry Jilin University Changchun 130012 P. R. China Department of Medicinal Chemistry University of Kansas Kansas 66045 USA College of Chemistry and Biology of Beihua University Jilin 132033 P. R. China

A series of HZSM-5 zeolites modified with different amounts of phosphoric acid（P/HZSM-5） was prepared. The physicochemical features of the P/HZSM-5 catalysts were characterized via X-ray diffraction（XRD）, N2 adsorption-desorption, NH3-temperatttre programmed desorption（NH3-TPD） and Fourier tranform infrared（FTIR） spectra of the adsorbed pyridine, and the performances of the catalysts for Prins condensation to isoprene from isobutylene and formaldehyde were investigated. The maximum isobutene conversion and isoprene selectivity were 10.3% and 94.6% on the HZSM-5 catalyst with a Si/A1 molar ratio of 600 using 5%（mass fraction） phosphoric acid. The phosphoric acid modification not only modulated the amount of acidic sites but also regulated the acid type. An appropriate amount of weak Lewis and Bronsted acid sites served as the active sites for the condensation of isobutene with formaldehyde, and the strong acid sites could cause side reactions and coke deposition.

关键词： isobutylene Isoprene Formaldehyde HZSM-5 catalyst Phosphoric acid modification

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Thermodynamic study of direct amination of isobutylene to tert-butylamine

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Chinese Journal of Catalysis 2017年第1期38卷 106-114页

作者： Shangyao Gao Xiangxue Zhu Xiujie Li Yuzhong Wang Ye Zhang Sujuan Xie Jie An Fucun Chen Shenglin Liu Longya Xu Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 Liaoning China University of Chinese Academy of Sciences Beijing 100049 China PetroChina Fushun Petrochemical Company Fushun 113004 Liaoning China

On basis of thermodynamic empirical equations, the thermodynamic parameters for the direct amination of isobutylene to tert‐butylamine, an atomically economic and green chemical reaction,were calculated. In particular, the equilibrium conversion of isobutylene under various reactionconditions close to those used in industry was calculated and discussed. isobutylene amination is atemperature sensitive reaction due to its exothermic nature and isobutylene equilibrium conversiondecreases with temperature. However, kinetically, the amination reaction will be faster at ahigher temperature. Thus, there must be an optimum temperature for the reaction. A high pressureand n(NH3)/n(i‐C4H8) molar ratio promote the transformation of isobutylene to tert‐*** a highly efficient catalyst under mild reaction conditions is preferred for the aminationprocess. The reaction was investigated over a series of acidic zeolites. ZSM‐11 zeolite exhibited thebest performance with 14.2% isobutylene conversion (52.2% of the equilibrium conversion) and >99.0% tert‐butylamine selectivity. The effect of reaction conditions on the performance of the ZSM‐11 catalyst agreed with the thermodynamic results, which provides guidance for further catalyst development and reaction condition optimization.

关键词： Thermodynamic calculation isobutylene Amination Tert-butylamine ZSM‐11 zeolite

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Direct amination of isobutylene over zeolite catalysts with various topologies and acidities

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Journal of Energy Chemistry 2017年第4期26卷 776-782页

作者： Shangyao Gao Xiangxue Zhu Xiujie Li Yuzhong Wang Sujuan Xie Songwei Du Fucun Chen Peng Zeng Shenglin Liu Longya Xu Dalian Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences PetroChina Jinzhou Petrochemical Company China Huanqiu Contracting and Engineering Corporation

The atomically economic and green chemical reaction of direct amination of isobutylene to tertbutylamine, particularly under the relative mild reaction conditions available for future industrial use,was carried out over zeolite catalysts possessing different topological structures, from one dimensional to three dimensional pore system, and from small 8-member ring pore（MRP） to medium 10 MRP and further to large 12 MRP zeolites, to disclose the relationship between the zeolite properties/topologies and their amination performance systematically under the mild reaction conditions. It was discovered that the pore structure and the acidities of zeolite catalysts played crucial roles in the isobutylene amination process, and suitable pore diameter（larger than 0.5 nm or with large side pockets/cups in the outside surface） and a certain number of mid-strong acid sites are indispensable to catalyze the amination reaction,while too strong acid strength was not conducive to the process of isobutylene amination. Among them,zeolites with topologies of BEA, MFI, MEL, MWW and EUO exhibited good amination performance, with which the isobutylene conversion was higher than 12.61%（>46.42% of the equilibrium conversion） under the studied mild reaction conditions. Due to the good amination performance and the large adjustable Si/Al;ratio range, ZSM-5 was selected to further study the effect of acidity on the amination performance systematically under the mild reaction conditions, and the activity-acidity relationship in the amination process was disclosed: the amination activity（isobutylene conversion） had a linear correlation with the amount of mid-strong B acidity under the studied conditions over ZSM-5 catalyst, which can provide guidance for further developing high-efficient amination catalyst under mild reaction conditions available for future industrial use.

关键词： isobutylene Amination Tert-butylamine Zeolite catalysts ZSM-5

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Selective Oxidation of isobutylene over Cs-promoted Mo-Bi-Co-Fe-Ce-O Catalyst

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Chinese Journal of Chemical Engineering 2005年第5期13卷 705-708页

作者：王蕾李增喜张锁江张香平赵威 Institute of Process Engineering Chinese Academy of Sciences

Cs-promoted Mo-Bi-Co-Fe-Ce-O catalyst for the selective oxidation of isobutylene to methacrolein had been studied in a fixed bed micro-reactor. The selectivity to methacrolein was significantly improved by the addition of Cs, which could probably enhance the dehydrogenation ability and weaken the oxygenation ability of the catalyst based on temperature programmed reduction （TPR） analysis investigation. The kinetic studies indicated that the oxidation of isobutylene to methacrolein followed the first-order kinetic behavior.

关键词： isobutylene selective oxidation complex catalyst kinetics

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Zeolite beta based FCC additives with good ability for LCO conversion and high isobutylene yield

Zeolite beta based FCC additives with good ability for LCO c...

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第十三届全国工业催化技术及应用年会

作者：刘其武 Pang Xinmei Cui Yan Xing Xin Guo Chengyu Li Zhaofei Wang Qian Wang Xiaohua Petrochemical Research Institute PetroChina Company Limited

Zeolite beta materials were carefully prepared,and then FCC catalysts were fabricated based on *** catalytic cracking performance was characterized by ACE *** was found that zeolite beta was a promising material in conversion of LCO and increase of isobutylene yield in FCC *** and ZSM-5 materials were also used as the active components to fabricate the catalyst and their catalytic performance were *** performance differences were attributed to their difference in the pore structure and acidic properties.

关键词： zeolite beta FCC LCO isobutylene

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SYNTHESIS OF HIGH MOLECULAR WEIGHT POLYisobutylene VIA CATIONIC POLYMERIZATION AT ELEVATED TEMPERATURES

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Chinese Journal of Polymer Science 2013年第8期31卷 1139-1147页

作者： Qiang Huang Ping He Jue Wang 吴一弦 State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology

A novel simple but effective initiating system of H2O/AlCl3/veratrole （VE） has been developed to synthesize high molecular weight polyisobutylene （PIB） at elevated temperatures via cationic polymerization of isobutylene （IB） in solvent mixture of hexane/methylene dichloride （n-Hex/CH2Cl2 = 2/1, V/V）. VE played very important roles in decreasing cationicity of the growing chain ends, suppressing side reactions of chain transfer and termination during polymerization, leading to production of high molecular weight PIBs. PIBs with high yields, having very high weight-average molecular weight （Mw） of 1117000 and 370000 g/tool could be synthesized with H2O/AICl3/VE initiating system at VE concentration of 5.4 mmol/L at -80 and -60 ℃ respectively. Molecular weight of PIB increased remarkably with increasing VE concentration. The reaction order with respect to VE concentration was determined to be -3.52 via FTIR spectroscopy in combination with a diamond tipped attenuated total reflectance （ATR） immersion probe. The negative reaction order of VE was consistent with its retarding effect on IB polymerization by interacting with the propagating species. Molecular weight of PIB decreased with increasing polymerization temperature. The activation energy for polymerization degree （Eop） could be determined to be around -23 kJ/mol when VE concentration was 5.4 mmol/L or 6.4 mmol/L.

关键词： isobutylene Molecular weight Cationic polymerization Polyisobutylene Kinetics.

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聚异丁烯类生物材料肝素化的表征

聚异丁烯类生物材料肝素化的表征

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2014年全国高分子材料科学与工程研讨会

作者：阮梦楠伍一波郭文莉李树新武海川张兰北京化工大学材料科学与工程学院北京石油化工学院材料科学与工程学院

＜正＞在当今世界,冠心病作为一种最常见、最严重的疾病危害着人类健康。如今,再狭窄率已经不是衡量药物洗脱支架疗效的唯一指标。促进内皮愈合,防止血栓形成具有重要意义。肝素是一种天然硫酸多糖类化合物,具有很强的抗凝血性,在开发... 详细信息

＜正＞在当今世界,冠心病作为一种最常见、最严重的疾病危害着人类健康。如今,再狭窄率已经不是衡量药物洗脱支架疗效的唯一指标。促进内皮愈合,防止血栓形成具有重要意义。肝素是一种天然硫酸多糖类化合物,具有很强的抗凝血性,在开发抗凝血生物材料的工作中,使材料表面肝素化被普遍认为是改进材料抗凝血性能最好的方法之一。肝素化抗凝血生物材料已成为高分子与生命科学相互渗透的一个重要边缘领域和研究热点。肝素化抗凝血生物材料一

关键词： 4-(2-hydroxyethyl)styrene isobutylene method of infrared spectrum

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