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1.
以蒽醌、溴苯等为主要起始原料,通过蒽的1位及9、10位取代,合成了1-甲氧基-9,10-二苯基蒽(MDPA)。改进和优化了各步合成工艺条件:在汞盐催化下,当反应温度为130℃,发烟硫酸浓度为20%-25%,反应时间为1.5h时,中间体蒽醌-1-硫酸钾收率为53.7%;采用苯基锂与1.甲氧基蒽醌加成后,直接用SnCl2的乙酸水溶液还原,产品收率为68.9%。测试了MDPA在PE农膜中的转光性质。结果表明,将MDPA掺入PE树脂中而形成的蓝光膜能在波长438nm处光致发光,该波长与植物光合作用所需的蓝光区相吻合;与普通农膜相比,蓝光膜可促进作物生长,使白菜、茼蒿、莴笋等蔬菜产量增加20%左右。 相似文献
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以大黄素(Ⅱ)为原料,在丙酮中与硫酸二甲酯〔n(Ⅱ)∶n(硫酸二甲酯)=1∶20〕反应24 h得到1,3,8-三甲氧基-6-甲基-9,10-蒽醌(Ⅲ),收率为95%;Ⅲ在过氧化苯甲酰及光引发下与N-溴代丁二酰亚胺(NBS)〔n(Ⅲ)∶n(NBS)=1∶3.45〕在四氯化碳中反应25 h得到1,3,8-三甲氧基-6-二溴甲基-9,10-蒽醌(Ⅳ),收率为70%;Ⅳ在甲氧基乙醇中水解10 m in,经氯仿萃取得1,3,8-三甲氧基-6-甲酰基-9,10-蒽醌(Ⅴ),收率为96%;最后化合物Ⅴ在氮气保护及冰水浴条件下与三溴化硼〔n(Ⅴ)∶n(BB r3)=1∶10〕反应2 h,合成了目标化合物1,3,8-三羟基-6-甲酰基-9,10-蒽醌(Ⅰ),总收率为47.2%。 相似文献
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合成了叔戊基蒽醌法生产双氧水工作液中主要的氢化和氧化降解产物。以苯和叔戊基氯为原料,合成了氢化降解产物:2-叔戊基-9-蒽酮、2-叔戊基蒽,当以2-叔戊基蒽醌(20mmol,5.56g)为基准,分12次间隔10min每次加入nHCl∶nSn=5.6mmol∶2.8mmol时,2-叔戊基-9-蒽酮的收率最高,达到65.8%,2-叔戊基蒽的收率达到16.4%;合成了氧化降解产物:2-叔戊基四氢蒽醌环氧化物,当nNaOH∶nH2O2=1∶1时,收率达到95.0%,后处理简单。 相似文献
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以间甲氧基苯甲醛为起始原料,20℃下与硝基甲烷反应2h得到3-甲氧基-β-硝基苯乙烯,收率88%。氢化铝锂为还原剂,无水四氢呋喃作溶剂,室温条件下反应4h,得到3-甲氧基苯乙胺,收率85.4%。100℃条件下,先与甲醛水溶液反应,再与20%盐酸反应得到6-甲氧基四氢异喹啉,收率80%。在RaneyNi作用下,190℃反应5h脱氢得到6-甲氧基异喹啉,收率86.5%。然后浓硫酸介质中,N-溴代丁二酸亚胺作用下,-5℃反应5h得到6-甲氧基-5-溴代异喹啉,收率93%。无水二甲基亚砜溶剂,氰化亚铜190℃反应2h氰解得到5-氰基-6-甲氧基异喹啉,收率95%。该化合物是一种重要的药物中间体和染料中间体,产品经过核磁共振和红外光谱检验确定结构。 相似文献
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《高校化学工程学报》2021,35(5)
2-戊基蒽是氧化法合成2-戊基蒽醌工艺的关键原料。以蒽和叔戊醇为原料经Friedel-Crafts烷基化合成了2-戊基蒽,由核磁共振氢谱(1H NMR)表征其结构,并考察催化剂、溶剂、反应物的量比、温度和时间对反应的影响。以烷基化的主要副产物二戊基蒽为原料,经烷基转移反应合成了2-戊基蒽,考察了催化剂、溶剂、温度、时间和反应物的量比对反应的影响。结果表明,AlCl3在烷基化和烷基转移反应中均具有良好的低温催化活性。在最佳烷基化反应条件下,蒽的转化率为92.8%,2-戊基蒽的收率为76.3%;在最佳烷基转移反应条件下,二戊基蒽的转化率为85.0%,2-戊基蒽的收率为68.9%。 相似文献
7.
以邻苯二甲酸酐和对苯二酚为初始原料,采用2种不同方法合成了1,4-二[(2-氨乙基)氨基]-9,10-蒽二酮。考察了时间、温度、物料比等因素对1,4-二[(2-氨乙基)氨基]-9,10-蒽二酮收率的影响。适宜的反应条件为:n(1,4-二羟基蒽醌)∶n(乙二胺)=1∶20,反应温度50℃,反应时间1 h。以1,4-二[(2-氨乙基)氨基]-9,10-蒽二酮为原料,与生物素缩合合成了由生物素介导的1,4-二[(2-氨乙基)氨基]-9,10-蒽二酮,收率为89.8%。 相似文献
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以1-乙酰氧基-4-甲氧基-9,10-蒽醌和β-酮酸酯(丙二酸二乙酯、乙酰乙酸乙酯和苯甲酰乙酸乙酯)为主要原料,碳酸钾为碱,经离子液体促进的Knoevenagel缩环反应合成了标题类化合物。合成条件为n(1-乙酰氧基-4-甲氧基-9,10-蒽醌)∶n(β-酮酸酯)∶n(碳酸钾)=1∶1.5∶5,反应温度为40℃,离子液体为[Mmim][DMP],所得产物收率分别为85.0%、50.0%、65.0%。产物及中间体经~1HNMR、~(13)CNMR、LC-MS和HRMS方法进行确证。比较了离子液体相对于有机溶剂对反应的影响,考察了离子液体类型、反应温度、碱及用量对反应收率的影响。实验结果表明,离子液体中反应收率优于常规有机溶剂,对反应有促进作用,离子液体[Mmim][DMP]中产物收率最高,反应温度适中,较高会导致原料分解,无机碱更适合β-酮酸酯为底物的反应。 相似文献
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PE吹塑农用兰光母料及兰光膜的研制 总被引:7,自引:0,他引:7
本文介绍PE吹塑农用兰光母料及兰光膜的研制。通过试验,确定了兰光母料的最佳配方,母料中光转换剂C_(26)H_(16)的用量为0.06~0.08%。并以母料与基体树脂1∶25的配比原材料,吹塑成兰光膜。此膜在光照不足的弱光照射下(2万LUX以下)光透过率>75%;存放13个月后物理机械性能未出现明显变劣趋势;其耐水浸渍性较好,完全可满足播种、移栽、整个育秧生长期的实际使用期限。该膜不仅是水稻育秧专用膜,而且还可用于玉米、红薯、西瓜等作物的增产增收。 相似文献
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Preparation of HDPE/UHMWPE/MMWPE blends by two-step processing way and properties of blown films 总被引:1,自引:0,他引:1
Jian-Dong Zuo Ya-Min Zhu Shu-Mei Liu Zhi-Jie Jiang Jian-Qing Zhao 《Polymer Bulletin》2007,58(4):711-722
Summary Blends of high density polyethylene (HDPE) and ultra high molecular weight polyethylene (UHMWPE) were prepared by two-step
processing way. Middle molecular weight polyethylene (MMWPE) as a fluidity modifier and compatilizer was added into UHMWPE
in the first step, and then modified UHMWPE and HDPE were blending extruded to prepare the HDPE/UHMWPE/MMWPE blends used for
blown films. The mechanical test of the blown films revealed that when the content of MMWPE in modified UHMWPE was 40wt% and
the content of UHMWPE in the blends was 20 wt%, the film had the optimal mechanical properties. The tensile strength and tear
strength of the film increased by 50% and 21%, respectively, compared with those of pure HDPE film. Rheological curves indicated
that the melt torque and the apparent viscosity of the HDPE/UHMWPE/MMWPE blends made by two-step processing way both greatly
reduced than other blends. The results from DSC suggested that the blends by two-step processing way may form more stable
and perfect co-crystallization. PLM (polarized light microscopy) and SEM micrographs revealed that two-step processing way
can improve the surface morphology of the films and make the dispersion of UHMWPE particles in HDPE increase. 相似文献
13.
Wenfei Li Zhanhai Yao Yue Yuan Yue Meng Lei Xie 《Polymer-Plastics Technology and Engineering》2013,52(6):620-625
A reactive type dripping agent, glycerol monolauric acid monoitaconic acid diester (GLID) was synthesized in our laboratory. Grafting-copolymerization of linear low density polyethylene (LLDPE) with GLID was carried out by using β-ray irradiation in air in a twin-screw extruder. FT-IR was used to characterize the formation of grafting copolymer and evaluate their degree of grafting. The effects of monomer concentration, reaction temperature and screw run speed on degree of grafting were studied systematically. Crystallization rates of grafted LLDPE were faster than that of plain LLDPE at a given crystallization temperature. The tensile properties and light transmission of blown films were determined. Comparing with neat LLDPE film, no obvious changes could be found for the tensile strength, elongation at break and right angle tearing strength of LLDPE-g-GLID film. Acceleration dripping property of film samples was investigated. The dripping duration of LLDPE-g-GLID film and commercial antifog dripping film at 60° C were 69 days and 17 days, respectively. 相似文献
14.
G. Flodberg A. Hellman M. S. Hedenqvist E. R. Sadiku U. W. Gedde 《Polymer Engineering and Science》2000,40(9):1969-1978
Blends of an extrusion‐grade polyethylene and two different liquid crystalline polymers of Vectra type were prepared by melt mixing using poly(ethylene‐comethacrylic acid) as compatibilizer. Oxygen and water vapor permeability, transparency and welding strength of compression molded and film blown specimens were studied. The compression molded blends showed gas permeabilities conforming to the Maxwell equation assuming low permeability liquid crystalline polymer spheres in a high permeability polyethylene matrix. One of the liquid crystalline polymers with suitable rheological properties formed a more continuous phase in the film blown blends and a substantial decrease in oxygen and water vapor permeability was observed in these blends. The compression molded blends with 50% liquid crystalline polymer and some of blow molded blends showed very high gas permeabilities. It is believed that voids forming continuous paths through the structure were present in these samples. The blends showed significantly higher opacity than pure polyethylene. 相似文献
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The structure of blown film processed from linear low density polyethylene blended with up to 30 wt[percnt] of a high melt strength polypropylene (hmsPP) was examined using primarily atomic force microscopy and wide angle X-ray scattering. The study focused on two polyethylene resins with the same density: a conventional Ziegler-Natta catalyzed linear low density polyethylene (znPE) and a blend of a Ziegler-Natta catalyzed and a metallocene catalyzed linear low density polyethylene (zn/mPE). Parallel characterization was performed on blown film of the hmsPP and blown film of each of the polyethylene resins. In films of the blends, the hmsPP was well-dispersed in the polyethylene matrix as elongated domains. In the domains, the hmsPP crystallized as planar row-nucleated structures with the long axis of the lamellae perpendicular to the extrusion direction. Row-nucleated hmsPP lamellae provided a template for epitaxial crystallization of polyethylene lamellae. The 42° angle of the lattice match imparted a characteristic herringbone texture to the polyethylene. Blending with hmsPP increased the tensile modulus and strength of polyethylene film without significantly affecting the ultimate elongation. 相似文献
17.
Matthew B. Johnson Garth L. Wilkes Ashish M. Sukhadia David C. Rohlfing 《应用聚合物科学杂志》2000,77(13):2845-2864
In this article we report on some surprising, and we believe new, findings regarding the factors affecting the optical properties (haze) of polyethylene blown and cast films. A comprehensive investigation of blown and cast films made from conventional Ziegler‐Natta catalyzed linear low density polyethylene (LLDPE) as well as metallocene‐catalyzed LLDPE (mLLDPE) resins was conducted. The large majority of the contribution to the total haze in the blown and cast films was observed to come from the surface roughness of the films, with the bulk (internal) contribution being relatively minor. Using a variety of analysis and characterization methods, including atomic force microscopy, small angle light scattering, and wide angle X‐ray scattering, we determined that the surface roughness in these films was a result of the development of distinct spherulitic‐like superstructures formed during the blown or cast film processing. Furthermore, these superstructures were observed only in the mLLDPE blown films, and not in the LLDPE blown films processed at similar conditions. Analysis of the rheological and molecular characteristics of these various mLLDPE and LLDPE resins revealed that the mLLDPE resins exhibited considerably lower molecular weight, narrower molecular weight distribution, lower zero shear viscosity, and lower melt elasticity compared with the LLDPE resins of similar melt index. These observations support our general finding and primary conclusion from this work that in polyethylene blown and cast films made using typical processing conditions, the optical haze properties are adversely affected because of enhanced surface roughness caused by the formation of spherulitic‐like superstructures in polymer melts that possess fast relaxing and low melt elasticity rheological characteristics. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 2845–2864, 2000 相似文献
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Three-layer coextruded blown (either blend or composite) films, made of low-density polyethylene and linear lowdensity polyethylene (1:1 ratio) of identical density, were compared. The tensile properties of both systems are nearly as high as those of the linear polyethylene while high strain rate properties including impact strength and tear resistance of the composite film are superior. Some structural insight was obtained by thermal analysis and thermoelastic measurements. Structure property relationships are discussed in light of the unique behavior, structure, and morphology of linear low-density polyethylene. The two polyethylenes are only compatible to a rather limited extent mainly affecting their blend behavior. However, a strong mutual reinforcement effect was observed. 相似文献
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Various linear low‐density polyethylene (LLDPE; density ~ (0.920 g/cm3)) resins that encompass those polymerized using Ziegler‐Natta, metallocene, and chromium oxide based catalysts were blown into film at similar process conditions, and the tensile properties of the resulting films were investigated in relation to their orientation characteristics. The tensile properties of the subject blown films were observed to be significantly different from those of isotropic/un‐oriented polyethylene specimens of similar density (crystallinity). Further, the tensile properties were different in the machine and transverse directions. These were explained in terms of the orientation and lamellar organization characteristics of the LLDPE blown films. Investigation of the temperature dependence (between ?50°C and +50°C) of these tensile properties indicated an increase in modulus, yield stress and break stress with decreasing temperature pointing to the possible role played by the decreased mobility of the non‐crystalline phase at lower temperatures. Excellent correlation between the Elmendorf tear properties of the LLDPE blown films and their tensile yield characteristics was observed. This added substantial credibility to previous hypotheses that specimen stretching plays a significant role in Elmendorf tear tests and further supported the previously identified structural features and microstructural deformation mechanisms that are deemed responsible for the discernment of LLDPE blown film tear resistance. 相似文献