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Non-phosgene synthesis of hexamethylene-1,6-diisocyanate from thermal decomposition of hexamethylene-1,6-dicarbamate over Zn–Co bimetallic supported ZSM-5 catalyst 被引量:2
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作者 Yan Cao Yafang Chi +3 位作者 Ammar Muhammad Peng He liguo Wang Huiquan Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第3期549-555,共7页
A non-phosgene route for the synthesis of hexamethylene-1,6-diisocyanate(HDI) was developed via catalytic decomposition of hexamethylene-1,6-dicarbamate(HDC) over Zn–Co bi-metallic supported ZSM-5 catalyst.The cataly... A non-phosgene route for the synthesis of hexamethylene-1,6-diisocyanate(HDI) was developed via catalytic decomposition of hexamethylene-1,6-dicarbamate(HDC) over Zn–Co bi-metallic supported ZSM-5 catalyst.The catalyst was characterized by FTIR and XRD analyses. Three solvents dioctyl sebacate(DOS), dibutyl sebacate(DBS) and 1-butyl-3-methylimidazolium tetrafluoroborate(BMIMBF_4) were investigated and compared; DOS gave better performance. The catalytic performances for thermal decomposition of HDC to HDI using DOS as solvent were then investigated, and the results showed that, under the optimized reaction conditions, i.e.,10 wt%concentration of HDC in DOS, 250 °C temperature, 60 min reaction time, 83.8% yield of HDI had been achieved over Zn–Co/ZSM-5. Decomposition of the intermediate hexamethylene-1-carbamate-6-isocyanate(HMI) over Zn–Co/ZSM-5 in DOS solvent was further studied and the results indicated that yield of HDI from HMI reached to 69.6%(98.6% HDI selectively) at 270 °C, which further increased the yield of the total HDI(HDI_(tol)) to as high as 95.0%. Recycling of catalyst showed that HDI and HMI yield slightly decreased, and by-product yield increased after the catalyst was reused for 4 times. At last possible reaction mechanism was proposed. 展开更多
关键词 NON-PHOSGENE Thermal decomposition Hexamethylene-1 6-diisocyanate Hexamethylene-1 6-dicarbamate BIMETALLIC SUPPORTED ZSM-5 catalyst
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An efficient green route for hexamethylene-1,6-diisocyanate synthesis by thermal decomposition of hexamethylene-1,6-dicarbamate over Co3O4/ZSM-5 catalyst: An indirect utilization of CO2 被引量:4
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作者 Muhammad Ammar Yan Cao +3 位作者 Peng He Liguo Wang Jiaqiang Chen Huiquan Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第12期1760-1770,共11页
The utilization of CO2 as raw material for chemical synthesis has the potential for substantial economic and green benefits. Thermal decomposition of hexamethylene-1,6-dicarbamate (HDC) is a promising approach for i... The utilization of CO2 as raw material for chemical synthesis has the potential for substantial economic and green benefits. Thermal decomposition of hexamethylene-1,6-dicarbamate (HDC) is a promising approach for indirect utilization of CO2 to produce hexamethylene-1,6-diisocyanate (HDI). In this work, a green route was developed for the synthesis of HD1 by thermal decomposition of HDC over Co3O4/ZSM-5 catalyst, using chlorobenzene as low boiling point solvent. Different metal oxide supported catalysts were prepared by incipient wetness impregnation (IWI), PEG-additive (PEG) and deposition precipitation with ammonia evaporation (DP) methods. Their catalytic performances for the thermal decomposition of HDC were tested. The catalyst screening results showed that Co3O4/ZSM-525 catalysts prepared by different methods showed different performances in the order of Co3O4/ZSM-5 25(PEG) 〉 Co3O4/ZSM-525(IWI) 〉 Co3O4/ZSM-525(DP). The physicochemical properties of Co3O4/ZSM- 52s catalyst were characterized by XRD, FTIR, N2 adsorption-desorption measurements, NH3-TPD and XPS. The superior catalytic performance of Co3O4/ZSM-52S(PEG) catalyst was attributed to its relative surface content of Co3 +, surface lattice oxygen content and total acidity. Under the optimized reaction conditions: 6.5% HDC concentration in chlorobenzene, 1 wt% Co3O4/ZSM-525(PEG) catalyst, 250℃ temperature, 2.5 h time, 800 ml.min 1 nitrogen flow rate and 1.0 MPa pressure, the HDC conversion and HDI yield could reach 100% and 92.8% respectively. The Co3O4/ZSM-525(PEG) catalyst could be facilely separated from the reaction mixture, and reused without degradation in catalytic performance. Furthermore, a possible reaction mechanism was proposed based on the physicochemical properties of the Co3O4/ZSM-5 25 catalysts. 展开更多
关键词 Hexamethylene-1 6-dicarbamate (HDC)Hexamethylene-1 6-diisocyanate (HDI) Thermal decomposition Co3O4/ZSM-5 Heterogeneous catalyst
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Zn-Co bimetallic supported ZSM-5 catalyst for phosgene-free synthesis of hexamethylene–1,6–diisocyanate by thermal decomposition of hexamethylene–1,6–dicarbamate 被引量:1
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作者 Muhammad Ammar Yan Cao +3 位作者 Peng He Li-Guo Wang Jia-Qiang Chen Hui-Quan Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2017年第7期1583-1589,共7页
A set of mono-and bimetallic(Zn-Co) supported ZSM-5 catalysts was first prepared by PEG-additive method. The physicochemical properties of the catalysts were investigated by FTIR, XPS, XRD, N2adsorption-desorption m... A set of mono-and bimetallic(Zn-Co) supported ZSM-5 catalysts was first prepared by PEG-additive method. The physicochemical properties of the catalysts were investigated by FTIR, XPS, XRD, N2adsorption-desorption measurements, SEM, EDS and NH3-TPD techniques. The physicochemical properties showed that the Zn Co2O4 spinel oxide was formed on the ZSM-5 support and provided effectual synergetic effect between Zn and Co species for the bimetallic catalyst. Furthermore, bimetallic supported ZSM-5 catalyst exhibited weak, moderate and strong acidic sites, while the monometallic supported ZSM-5 catalyst showed only weak and moderate or strong acidic sites. Their catalytic performances for thermal decomposition of hexamethylene–1,6–dicarbamate(HDC) to hexamethylene–1,6–diisocyanate(HDI) were then studied. It was found that the bimetallic supported ZSM-5 catalysts,especially Zn-2Co/ZSM-5 catalyst showed excellent catalytic performance due to the good synergetic effect between Co and Zn species, which provided a suitable contribution of acidic sites. HDC conversion of 100% with HDI selectivity of 91.2% and by-products selectivity of 1.3% could be achieved within short reaction time of 2.5 h over Zn-2Co/ZSM-5 catalyst. 展开更多
关键词 Hexamethylene–1 6–dicarbamate(HDC) Hexamethylene–1 6–diisocyanate(HDI) Thermal decomposition Bimetallic supported ZSM-5 catalyst Synergetic effect
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NDI型聚氨酯弹性体的氢键研究 被引量:7
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作者 余成科 崔屹 +2 位作者 付会娟 毛立新 张立群 《北京化工大学学报(自然科学版)》 CAS CSCD 北大核心 2012年第6期52-57,共6页
采用预聚物法合成了以聚四氢呋喃醚二醇(PTMG)、聚氧化丙烯二醇(PPG)、1,5-萘二异氰酸酯(NDI)、1,4-丁二醇(BDO)、三羟甲基丙烷(TMP)等为主要原料的双组分浇注型聚氨酯弹性体。通过红外分析、差示扫描量热分析,对NDI型聚氨酯弹性体中存... 采用预聚物法合成了以聚四氢呋喃醚二醇(PTMG)、聚氧化丙烯二醇(PPG)、1,5-萘二异氰酸酯(NDI)、1,4-丁二醇(BDO)、三羟甲基丙烷(TMP)等为主要原料的双组分浇注型聚氨酯弹性体。通过红外分析、差示扫描量热分析,对NDI型聚氨酯弹性体中存在的氢键进行了深入研究。结果表明,NDI型聚氨酯弹性体的亚氨基(N—H)完全氢键化,羰基(CO)氢键化程度高,微相分离严重;随着预聚物中异氰酸根含量的增加,硬段微区氢键化程度逐渐提高,其中有序氢键化程度逐渐升高,而无序氢键化程度随之下降;PTMG2000-NDI系聚氨酯弹性体的软段容易产生结晶,而DL2000-NDI系聚氨酯弹性体和PTMG1000-NDI系聚氨酯弹性体的软段无结晶行为;低聚物多元醇的种类及其分子量也是聚氨酯弹性体的氢键的重要影响因素。 展开更多
关键词 1 5-萘二异氰酸酯 聚氨酯弹性体 氢键 低聚物多元醇
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TDI与DMTDA为硬链段的浇注型PU弹性体的合成与性能研究 被引量:4
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作者 陈晓东 周南桥 张海 《塑料工业》 CAS CSCD 北大核心 2008年第6期8-11,共4页
采用2,4-甲苯二异氰酸酯(TDI)和3,5-二甲硫基甲苯二胺(DMTDA)为硬段单体,与不同结构的软段(聚酯、聚醚)缩聚制备了浇注聚氨酯弹性体。研究了软段结构变化对聚氨酯弹性体的力学性能、耐湿、热性能、磨耗、耐溶剂性以及动态性能的影响。... 采用2,4-甲苯二异氰酸酯(TDI)和3,5-二甲硫基甲苯二胺(DMTDA)为硬段单体,与不同结构的软段(聚酯、聚醚)缩聚制备了浇注聚氨酯弹性体。研究了软段结构变化对聚氨酯弹性体的力学性能、耐湿、热性能、磨耗、耐溶剂性以及动态性能的影响。结果表明,PCL弹性体能够表现出PEA型弹性体的优良抗撕裂和应力-应变行为,同时又有类似PTMG型弹性体的突出压缩永久变形和回弹性能,而且具有较好的抗湿滑性能和良好的动态使用性能,其综合性能更加平衡。 展开更多
关键词 浇注聚氨酯弹性体 合成 2 4-甲苯二异氰酸酯 3 5-二甲硫基甲苯二胺
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磷酸酯阻燃改性MDI型水性聚氨酯的研究 被引量:6
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作者 吴鲁 郭景凤 赵殊 《中国胶粘剂》 CAS 北大核心 2017年第1期33-36,共4页
以二苯基甲烷二异氰酸酯(MDI)和聚乙二醇(PEG-600)为主要单体、N,N-双(2-羟乙基)氨基乙基膦酸二乙酯(FRC-5)为部分或全部扩链剂,制备了一系列不同FRC-5掺量的阻燃WPU(水性聚氨酯)。研究结果表明:当w(FRC-5)=15%(相对于PEG-600和MDI总质... 以二苯基甲烷二异氰酸酯(MDI)和聚乙二醇(PEG-600)为主要单体、N,N-双(2-羟乙基)氨基乙基膦酸二乙酯(FRC-5)为部分或全部扩链剂,制备了一系列不同FRC-5掺量的阻燃WPU(水性聚氨酯)。研究结果表明:当w(FRC-5)=15%(相对于PEG-600和MDI总质量而言)时,WPU胶膜的LOI(极限氧指数)为27%,同时热稳定性也有所提高;当w(FRC-5)=12%时,可得到性能稳定、阻燃性能较佳且胶膜平整的WPU。 展开更多
关键词 水性聚氨酯 阻燃 二苯基甲烷二异氰酸酯 N N-双(2-羟乙基)氨基乙基膦酸二乙酯
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The Identification of Two New Sterols from Marine Organism 被引量:3
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作者 Shi Hai XU Long Mei ZENG(Department of Chemistry, Jinan University Guanzhou 510632)(Department of Chemistry Zhongshan University Guanzhou 510275) 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第6期531-534,共4页
Two new sterol have been isolated from the South China Sea marine organism. Compound 1 was isolated from the sponge Polymastia sobustia and compound 2 was obtained from the soft coral Sinularia inexplicata. Their stru... Two new sterol have been isolated from the South China Sea marine organism. Compound 1 was isolated from the sponge Polymastia sobustia and compound 2 was obtained from the soft coral Sinularia inexplicata. Their structures were established as 3 beta-hydroxy-stigmast-5en-7-one and 24-methylene cholestan -3 beta, 6 beta, 9 alpha, 19-tetrol by variety of spectral analysis such as IR, EIMS, 1DNMR, H-1-H-1 COSY, HMQC, HMBC, NOESY. 展开更多
关键词 sterol Polymastia sobustia 3 beta-hydroxy- stigmast-5en-7-one soft coral Sinularia inexplicita 24-methylene cholestan-3 beta 6 beta 9 alpha 19-tetrol
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戊二胺在有机合成中的应用
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作者 秦兵兵 《化工中间体》 2015年第6期144-144,共1页
戊二胺作为一种新的有机合成中间体,在高温条件下,用分子筛或贵金属催化,可以高收率的得到吡啶或哌啶。戊二胺与光气反应,可以制备得到五亚甲基二异氰酸酯,该化合物制备得到的涂膜有独特的性能。
关键词 戊二胺 吡啶 哌啶 五亚甲基二异氰酸酯
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A new tetracyclic triterpenoid from endophytic fungus Fusarium sporotrichioides
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作者 Yajing Wang Chunyue Liu +2 位作者 Yihui Yang Chang Li Yuehu Pei 《Chinese Herbal Medicines》 CAS 2024年第2期231-234,共4页
Objective: To isolate bioactive compounds from the endophytic fungus Fusarium sporotrichioides isolated from Rauwolfia yunnanensis, and investigate their pharmacological activities.Methods: The chemical constituents w... Objective: To isolate bioactive compounds from the endophytic fungus Fusarium sporotrichioides isolated from Rauwolfia yunnanensis, and investigate their pharmacological activities.Methods: The chemical constituents were isolated and purified by combining with ODS column chromatography, silica gel column chromatography and by performing semipreparative HPLC. Their structures were established on the basis of 1D NMR(1H-NMR and13C-NMR) and 2D NMR(1H–1H COSY,HSQC, HMBC and NOESY), as well as HRESIMS and comparison with literature data. In addition, the absolute configuration of compound 1 was determined by calculated ECD data.Results: One previously undescribed tetracyclic triterpenoid derivative, named as integracide L(1), 12aacetoxy-4,4-dimethyl-24-methylene-5a-cholesta-8,14-diene-2a,3β,11β-triol(2), 12a-acetoxy-4,4-dime thyl-24-methylene-5a-cholesta-8-momoene-2a,3β,11β-triol(3), 12a-acetoxy-4,4-dimethyl-24-methy lene-5a-cholesta-8,14-diene-3β,11β-triol(4), and 12a-acetoxy-4,4-dimethyl-24-methylene-5acholesta-8-momoene-3β,11β-triol(5) were isolated from F. sporotrichioide. Moreover, compound 1 was rare tetracyclic triterpenoid with single methyl replacement at C-4 position.Conclusion: Compound 1 was a new tetracyclic triterpenoid isolated from the endophytic fungus F.sporotrichioides. In addition, compound 2 could inhibit the growth of three different human cancer cells significantly. Compounds 3 and 5 were found to possess better cytotoxic activities on Hep G-2 cells than the other compounds, with IC50values of(2.8 ± 0.1) and(6.3 ± 0.3) μmol/L respectively. 展开更多
关键词 antitumor Fusarium sporotrichioides integracide L tetracyclic triterpenoid 12a-acetoxy-4 4-dimethyl-24-methylene5a-cholesta-814-diene-2a 3b 11b-triol 12a-acetoxy-4 4-dimethyl-24-methylene5a-cholesta-8-momoene-2a 3b 11b-triol 12a-acetoxy-4 4-dimethyl-24-methylene5a-cholesta-8-momoene-3b 11b-triol
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