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1.
李华  鲁波  黄雁明  陈志荣 《化学世界》2005,46(6):358-361
2,3-二甲氧基-5-甲基-1,4-苯酚与2-甲基丁烯醇在BF3OEt2的催化下进行傅-克烷基化反应合成2,3-二甲氧基-5-甲基-6-(3-甲基-2-烯-1-丁基)-1,4-苯酚。对鲜见文献报道的副产物2,2,5-三甲基-3-氢-6-羟基-7,8-二甲氧基-苯并吡喃进行了结构鉴定并推测了其形成机理,在原料辅酶Q0、甲基丁烯醇和BR的配比为1:1.5:0.19(摩尔比),反应温度45℃,滴加时间30min,反应时间2h的条件下收率达90.24%。  相似文献   

2.
以正丁酸乙酯和草酸二乙酯为主要原料,合成了香料化合物3-乙基-2-羟基-2-环戊烯-1-酮。首先由正丁酸乙酯和草酸二乙酯经Claisen缩合生成2-乙基-3-羰基-丁二酸乙酯,其与丙烯酸乙酯发生Michael加成,随后Dieckmann酯缩合得到5-乙基-3,5-二乙酯基-2-羟基-2-环戊烯-1-酮,然后经水解脱羧获得3-乙基-2-羟基-2-环戊烯-1-酮。初步考察并优化了各步反应的工艺条件,产品总收率达44.46%。  相似文献   

3.
根据Kornblum反应,采用二甲基亚砜(DMSO)氧化E-1-乙酰氧基-4-氯-3-甲基-2-丁烯(ACMB)合成E-4-乙酰氧基-2-甲基-2-丁烯-1-醛(AMBA)。在实验过程中,采用气相色谱跟踪,研究了反应时问、反应温度和催化剂用量等因素对主副产物收率的影响并确定了较佳反应条件;反应时间24h,反应温度80℃,原料缓慢滴加,KH2PO4:K2HPO4:ACMB=0.14:1.27:1(摩尔比),催化剂用量与原料ACMB比为0.12:1(摩尔比)。同时,对从未报道过的副产物E-1-乙酰氧基-4-甲巯基-3-甲基-2-丁烯(AMMB)进行了结构鉴定,并推测了其形成机理。  相似文献   

4.
以1-氨基-2-溴-4-羟基-蒽醌和乙二醇为原料,在碱作用下脱溴得到1-氨基-4-羟基-蒽醌,收率92.O%。  相似文献   

5.
本文以4-氯-2-氨基苯酚为起始原料合成了4-氯-5-硝基-2-氨基苯酚。4-氯-2-氨基苯酚经醋酐酰化制得2-乙酰氨基-4-氯苯酚,粗产率为92.4%,熔点为170.3℃~171 3℃。然后分别以氯苯,邻二氯苯为脱水剂在回流条件下反应15小时,经真空蒸馏得到5-氯-2-甲基苯并(?) 唑,熔点为52℃-54℃。将5-氯-2-甲基苯并(?)唑进行硝化反应,得到5-氯-6-硝基-2-甲基苯并(?)唑,粗产率84.76%,熔点为135.5℃-139.0℃。5-氯-6-硝基-2-甲基苯并(?)唑在强碱条件下水解后,经酸析得到4-氯-5-硝基-2-氨基苯酚,粗产率为90.10%.熔点为209.8~210.0℃。  相似文献   

6.
2-甲基-3-丁烯-2-醇合成3-甲基-2-丁烯-1-醇   总被引:1,自引:0,他引:1  
颜延宁  朱斌 《农药》2011,50(12)
[目的]2-甲基-3-丁烯-2-醇是异戊二烯间接皂化法生产3-甲基-2-丁烯-1-醇过程中产生的副产物,废物回收再利用是节能减排的有效措施.[方法]2-甲基-3-丁烯-2-醇经氯化、酯化和皂化得到3-甲基-2-丁烯-1-醇.[结果]结果表明:在优化条件下,氯化反应的产率可达87.25%,酯化和皂化反应的产率可达84.53%.[结论]该方法是2-甲基-3-丁烯-2-醇再利用的有效方法.  相似文献   

7.
以2-氨基-4-氯苯酚为原料。经乙酰化、闭环、硝化、碱解和酸化合成2-氨基-4-氯-5-硝基苯酚,精制品总收率为64%。  相似文献   

8.
孙日圣  陈心勇  陈乐意  刘华祥 《化学世界》2006,47(4):220-221,231
以1-甲基-3-丙基吡唑-5-甲酸为原料,采用二氯甲烷为溶剂,合成了1-甲基-3-丙基-4-硝基吡唑-5-羧酸。试验研究了影响反应收率的多种因素,确定了最佳工艺条件:搅拌转速600 r/min;反应温度70°C;反应时间5~6 h;硫酸的浓度为90%。  相似文献   

9.
分别以(E)-1-苯基-1-丁烯-3-酮和4-苯基-2-丁酮为起始原料合成了3-羟基-4-苯基-2-丁酮。以(E)-1-苯基-1-丁烯-3-酮为起始原料,经过环氧化和还原两步反应得到产物;第1步环氧化反应,用双氧水作氧化剂,产率64%;第2步α,β-环氧酮在Pd/C催化作用下用甲酸还原,得到产物3-羟基-4-苯基-2-丁酮,产率67%;该路线总产率为43%。以4-苯基-2-丁酮为起始原料,经过烯醇硅醚中间体氧化得到产物;4-苯基-2-丁酮在六甲基二硅胺作用下与三甲基碘硅烷反应得到4-苯基-2-丁烯-2-基三甲基硅醚,产率为75%;第2步烯醇硅醚用间氯过氧苯甲酸氧化,得到产物3-羟基-4-苯基-2-丁酮,产率达71%;该路线总产率为53%。以(E)-1-苯基-1-丁烯-3-酮为起始原料的合成路线总产率略低,但操作简单,试剂价廉易得,是更为实用可行的合成路线。  相似文献   

10.
以甲基丁炔醇为起始原料合成3-氯-3-甲基-1-丁炔,液氨氨解得到2-甲基-3-丁炔-2-胺,并对合成条件进行了优化,探索出适合工业化生产的2-甲基-3-丁炔-2-胺的合成方法,产物用IR和GC-MS进行表征。  相似文献   

11.
对ABS/长玻璃纤维(LGF)及ABS/LGF/SMA(苯乙烯/马来酸酐共聚物)2种复合材料的界面形态、纤维效率系数和力学行为进行了研究。结果表明:界面粘结作用是影响力学性能和纤维效率系数的关键因素。对于ABS/LGF体系,弱的界面相互作用使材料表现出低的力学性能和纤维效率系数。而对于ABS/LGF/SMA体系,由于纤维和基体树脂之间的界面相互作用增强导致材料呈现出更高的力学强度,同时纤维效率系数也得到提高。  相似文献   

12.
对不同粘合体系,不同牌号钴盐在全钢子午线轮胎中的应用进行了探讨。结果表明。间甲白钴复合粘合体系综合性能最佳。不同钴盐对胶料物性和初始粘合无明显影响,硼酰化后的粘合保持率和覆胶率明显高于其它钴盐,尤其是耐汽老化和盐水老化性能较好。正交设计得出粘合体系主要因素最佳用量组合为间苯二酚1.5,粘合增进剂6,硫黄6.5,硼酰化钴1.1,大料及产品试验结果表明,优选配方达到技术指标和产品使用性能要求。  相似文献   

13.
The adhesion properties of polychloroprene can be improved by addition of such materials as piperylene–styrene co-polymer (PSC), VeoVa-10 polymer, VeoVa-11/methyl methacrylate/2ethylhexyl acrylate co-polymer (VeoVa-11/MMA/2EHA) and poly(vinyl acetate) waste (wPVAc). Here, the relationship between adhesion properties and surface tension of polychloroprene was investigated. Contact angle measurements have been used to study the effects of nature and content of polymeric additives on the adhesion and surface properties of polychloroprene. Low-surface-tension VeoVa-10 polymer has the tendency to migrate to the surface of polychloroprene; thus, adhesion is determined mainly by this additive property. Enrichment of polychloroprene film bottom layer by the additive was observed using high-surface-tension PSC and wPVAc. In this case, the adhesion properties of polychloroprene depend on the interactions at the interface. Adhesion properties of polychloroprene were found to depend not only on compatibility between adhesive components, but also on compatibility between the adherend and the adhesive.  相似文献   

14.
The JKR (Johnson-Kendall-Roberts) method of contact mechanics has been widely utilized for measuring adhesion properties between a deformable elastomeric lens and various materials. Such measurements are normally performed in air. We attempted to verify whether the JKR technique could be practical for evaluating adhesion properties under water. After modifying the common JKR apparatus to be suitable for underwater studies, two types of hydrophobic coating systems, silicone/silicone and silicone/silanized silicon wafer, were used. The work of adhesion (WA) values obtained from loading measurements and under zero load were found to be slightly smaller than the values estimated using surface energies and contact angles of water formed on the surfaces of these coatings. One possible cause for the slightly smaller values could be contamination/alteration of the coating surface properties upon immersion in water. The results suggested that, with proper control of experimental conditions, the JKR technique could be extended to evaluate adhesion properties under water.  相似文献   

15.
In this study, cement mortars were modified with a commercial polymer admixture. The aim of this study is to investigate the influence of the polymer content on the mechanical and adhesion properties of the mortars and to relate these properties with mortars’ microstructure. A series of mortars were produced with various polymer/cement/water/aggregate ratios. The adhesion properties of the mortars to clay bricks were tested with a simplified tensile testing measurement. The microstructure of mortars, as well as interfaces, were evaluated by Scanning Electron Microscopy (SEM). It was found that with high polymer content, large size hardened particles are formed, reducing the compressive strength of the mortars. Polymer addition enhances the adhesion between the mortar and brick. The mortar microstructure at the interface affects the adhesion properties and the mode of failure.  相似文献   

16.
Processing Polycarbonate/carbon fiber composites for long times at high temperatures significantly improved adhesion between the matrix and the fibers. The interfacial properties were studied by measuring transverse fracture toughness, observing fracture specimens by scanning electron microscopy, and by monitoring composite cross-sections using atomic force microscopy. The processing treatment provided an ideal method for varying the properties of the interface without changing any other properties. We used this method to study the effect of interfacial properties on the axial compression properties of unidirectional composites. Both the compression strength and compression modulus increased significantly as the fiber/matrix adhesion improved. We concluded that improving interfacial adhesion increased compression properties by inhibiting fiber microbuckling.  相似文献   

17.
粘合增进剂AIR-201对航空轮胎芳纶帘布胶性能的影响   总被引:1,自引:0,他引:1  
吴春齐  刘蓉  俞华英 《橡胶工业》2011,58(6):339-342
研究粘合增进剂AIR-201对航空轮胎芳纶帘布胶性能的影响.结果表明,在帘布胶中加入粘合增进剂AIR-201,胶料与芳纶帘线和芳纶/锦纶复合帘线热空气老化前后的粘合性能均明显提高,硫化胶邵尔A型硬度和300%定伸应力略有增大,其余物理性能变化不大.  相似文献   

18.
TiN/TaN multilayer coatings exhibit excellent mechanical properties when compared to single layer nitride coatings. In this study, TiN/TaN multilayer coatings were deposited on Mo-alloy and W-alloy substrates by CFUBMS. The structural and mechanical properties of coatings were analysed using XRD, EDS, SEM and a micro-hardness tester, respectively. To determine the adhesion and fatigue behaviour of the coatings were performed a scratch test in two modes that a standard mode with progressive loading and sliding-fatigue multimode operation with unidirectional sliding, respectively. A microscope was used to characterize adhesion and fatigue failures. The structural, mechanical, adhesion and fatigue properties of TiN/TaN multilayer coatings significantly changed depending on the substrate.  相似文献   

19.
纤维增强树脂基复合材料界面粘结强度测试方法探讨   总被引:9,自引:2,他引:9  
基体和增强材料界面的粘结性能直接影响到复合材料的力学性能,如何测量复合材料界面的粘结强度是界面研究的关键问题之一。本文侧重回顾了目前使用的复合材料界面粘结强度测试方法,如微脱粘、单纤维复合材料断裂、单纤维拔出和压出法,并对相关的计算理论进行了扼要介绍。  相似文献   

20.
In this paper, the batch suspension copolymerization process for production of microsphere acrylic pressure-sensitive adhesives (PSA) is presented. The effects of different process and chemical parameters on adhesion properties are discussed. The reaction was monitored in-line by using attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy. Properties of the adhesive suspension (particle size), adhesive (gel phase, molecular weight, glass transition temperature (Tg)) and adhesion properties (tack, peel strength and shear) were determined. The results have shown that reaction kinetics strongly depends on polymerization temperature and initiator concentration. On the other hand, adhesion properties depend mainly on the Tg of the polymer and on the amount of insoluble gel fraction in the adhesive.  相似文献   

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