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1.
以4,4′-二(1-甲基-1-苯乙基)-二苯胺和硫磺为原料,碘催化合成3,7-二(1-甲基-1-苯乙基)-吩噻嗪。4,4′-二(1-甲基-1-苯乙基)-二苯胺与硫磺的摩尔比为1∶2,反应温度为200℃,反应时间6 h。采用熔点仪、HPLC、FT-IR、NMR、TGA和PDSC等表征方法对产物的纯度、结构、热稳定性能和抗氧化性能进行分析,结果表明,纯化后的3,7-二(1-甲基-1-苯乙基)-吩噻嗪纯度可达99.7%;相比于4,4′-二(1-甲基-1-苯乙基)-二苯胺,3,7-二(1-甲基-1-苯乙基)-吩噻嗪具有更好的高温热稳定性能和抗氧化性能。  相似文献   

2.
《广东化工》2021,48(2)
以N,N-二甲基甲酰胺为溶剂、K2CO3作为催化剂的,3,4-二羟基苯甲醛与氯二氟乙酸甲酯在70℃反应4小时,得到4-二氟甲氧基-3-羟基苯甲醛,产率为64.06%;以二氯甲烷为溶剂,投料摩尔比(DABD∶Ph3P)=1∶1.2,0℃投料后,室温反应2小时,4-二氟甲氧基-3-羟基苯甲醛和3-羟基四氢呋喃醚化合成4-(二氟甲氧基)-3(四氢呋喃-3-基氧基)苯甲醛,产率为86.25%;4-(二氟甲氧基)-3(四氢呋喃-3-基氧基)苯甲醛用高锰酸钾在丙酮和H2O中反应8小时氧化为4-(二氟甲氧基)-3-(四氢呋喃-3-基氧基)苯甲酸,并且收率为89.64%;用二氯亚砜将酸酰氯化后,不经分离在室温下与相应的胺在四氢呋喃中反应0.5小时生成4-(二氟甲氧基)-N-正丁基-3-(四氢呋喃-3-基氧基)苯甲酰胺类磷酸二酯酶(Ⅵ)的抑制剂。实验过程中通过HPLC,1H NMR等进行定性、定量分析和表征。  相似文献   

3.
对3,4-二氢-2(1H)喹啉酮衍生物1,2,3(R= NO2,NH2,OH;R= H,NO2,NH2)的合成进行了研究。以苯胺和3-氯丙酰氯为原料,制得N-苯基-3-氯丙酰胺,然后经环合得到3,4-二氢-2(1H)喹啉酮,再经由硝化、还原、重氮化水解合成了一系列3,4-二氢-2(1H)喹啉酮衍生物:6-硝基-3,4-二氢-2(1H)喹啉酮(1a),6,8-二硝基-3,4-二氢-2(1H)喹啉酮(1b),6-氨基-3,4-二氢-2(1H)喹啉酮(2a),6,8-二氨基-3,4-二氢-2(1H)喹啉酮(2b),6-氨基-8-硝基-3,4-二氢-2(1H)喹啉酮(2c),6-羟基-3,4-二氢-2(1H)喹啉酮(3a)和6-羟基-8-硝基-3,4-二氢-2(1H)喹啉酮(3b),其中化合物(2c)及(3b)为新化合物。单步产率均在86%以上,路线简单,操作简便,反应条件温和。采用MS,1HNMR对产品进行了定性及结构表征。  相似文献   

4.
以2-氰基吡啶和水合肼为原料,经过Pinner反应和氧化反应合成得到3,6-二(吡啶-2-基)-1,2,4,5-四嗪(化合物1),收率为88.6%。对影响产物收率的因素进行了考察,确定了第二步氧化反应的反应温度为0℃,反应时间1.0h。化合物1分别与6,7-二溴-1,4-二氢-1,4-环氧萘(化合物4a)和6,7-二甲氧基-1,4-二氢-1,4-环氧萘(化合物4b)反应得到5,6-二溴异苯并呋喃(化合物5a)和5,6-二甲氧基异苯并呋喃(化合物5b)的收率分别为51.3%和48.5%。化合物1和化合物5a以及化合物5b的结构均采用~1H-NMR和ESI-MS进行了表征。  相似文献   

5.
以甲醇钠为催化剂,采用2,6-二叔丁基苯酚、三聚乙醛为原料合成4,4’-乙撑二(2,6-二叔丁基苯酚),分别考察了反应温度、反应时间、原料配比、催化剂和溶剂用量等条件对缩合反应的影响。得到了合成4,4’-乙撑二(2,6-二叔丁基苯酚)最适宜的条件是:反应温度为125℃,反应时间8 h,n(2,6-二叔丁基苯酚)∶n(三聚乙醛)为0.2∶0.15;催化剂的用量为0.8 g、溶剂的用量为40 g(2,6-二叔丁基苯酚为0.2 mol的情况下)。4,4’-乙撑二(2,6-二叔丁基苯酚)的收率可达到91.75%以上,产品纯度w[4,4’-乙撑二(2,6-二叔丁基苯酚)]超过99.0%。  相似文献   

6.
以市售1,6,7,12-四氯-3,4,9,10-苝四甲酸二酐(TCPBA)为原料,合成了中间体N,N'-二(2,6-二异丙基)苯基-1,6,7,12-四氯-3,4,9,10-苝四甲酸二酰亚胺(BDIP-TCPBI)和产品N,N'-二(2,6-二异丙基)苯基-1,6,7,12-四苯氧基-3,4,9,10-苝四甲酸二酰亚胺(苝红620),其结构经IR、MS和NMR进行了确证。结果显示:反应中引入催化剂二水乙酸锌,使BDIP-TCPBI的合成时间缩短了一半,纯度(HPLC,下同)较文献纯度(68%)高出16%,其最佳工艺条件为:n(TCPBA)∶n(2,6-二异丙基苯胺)∶n(二水乙酸锌)∶n(丙酸)=1∶4∶0.2∶107,120℃反应12 h,产率为88%,纯度为84%;使用简便的洗涤代替柱色谱法使苝红620的纯度较文献纯度(82%)高出9%。苝红620的斯托克斯位移值为35 nm,循环伏安法获得苝红620的LUMO和HOMO轨道能级分别为–4.144和–4.470 e V,且具有较小的荧光自吸效应,是一种潜在的电子受体材料。  相似文献   

7.
2,2-二(3,5-二氨基-4-羟基苯基)丙烷是一种新型膨胀型阻燃剂和合成N-P系膨胀型阻燃剂的中间体。研究了Fe-A l/C催化水合肼还原2,2-二(4-羟基-3,5-二硝基苯基)丙烷合成2,2-二(3,5-二氨基-4-羟基苯基)丙烷的反应条件。结果表明:对20 mmol的反应物,Fe-A l/C催化剂的用量为0.6 g,反应温度为75℃,反应时间为5 h,物料比n〔2,2-二(4-羟基-3,5-二硝基苯基)丙烷〕∶n(水合肼)=1∶12时,还原产率为93.75%,w〔2,2-二(3,5-二氨基-4-羟基苯基)丙烷〕=96.5%(HPLC),Fe-A l/C催化剂可以重复使用7次。产物经元素分析、红外光谱、核磁共振和质谱分析确证。  相似文献   

8.
为控制盐酸氨溴索质量,以外购的有关物质E(2-氨基-3,5-二溴苯甲醛)为起始原料,合成了4个有关物质:2-氨基-3,5-二溴苯甲醇(有关物质A)、反式-4-(6,8-二溴-1,4-二氢喹唑啉-3(2H)-基)环己醇(有关物质B)、反式-4-[[(E)-2-氨基-3,5-二溴苯亚甲基]氨基]环己醇(有关物质C)和顺式-4-[(2-氨基-3,5-二溴苯甲基)氨基]环己醇(有关物质D),通过~1HNMR、~(13)CNMR和MS对产物结构进行了确证,并优化了醛胺缩合和还原反应条件。合成的这4个有关物质可作为盐酸氨溴索质量控制的杂质对照品。  相似文献   

9.
以2,4’-二氟二苯酮和锍盐(CH3)3SHSO4为原料,在碱性条件下反应生成1-(2-氟苯基)-1-(4-氟苯基)环氧乙烷。通过正交实验确定最佳工艺条件为:氢氧化钾、甲醇和2,4’-二氟二苯酮的物质的量比为6∶1.25∶1,反应温度45℃。以2,4’-二氟二苯酮计,产品收率为91.23%,含量为97.45%。  相似文献   

10.
根据四(2,4-二叔丁基苯基-4-4′-联苯基)双膦酸酯(即P-EPQ)的结构特点分析,拟定两步法合成路线:以联苯和三氯化磷为原料,在无水二氯化铝催化作用下,合成中间体4,4′-联苯基双二氯化膦,中间体再与2,4-二叔丁基苯酚发生酯化反应生成P-EPQ.确定第一步反应最佳工艺条件为:n(联苯):n(PCl3):n(AlCl3)为1:6:2.2,反应温度为75 ℃,反应时间为7 h;确定第二步反应最佳工艺条件为:n(2,4-二叔丁基苯酚):n(4,4′-联苯基双二氯化膦):n(三乙胺)为4.4:1:4.8,反应温度为132℃,反应时间为8 h.  相似文献   

11.
以聚酯多元醇为基的聚氨酯弹性体的动态力学性能研究   总被引:4,自引:0,他引:4  
合成了以聚酯多元醇为基的聚氨酯弹性体(PUE),研究了聚酯多元醇结构及相对分子质量、扩链剂类型及用量等因素对聚氨酯弹性体的动态力学性能的影响。结果表明:以相对分子质量为2000及3000的聚酯多元醇制得的PUE中存在明显的相分离;当扩链剂中带有苯环结构时,PUE的玻璃化转变温度(Tg)升高,储能模量增加,阻尼因子下降;PUE的Tg及储能模量随着扩链剂L-MOCA用量的增加线性升高,阻尼因子线性下降。  相似文献   

12.
IPDI基浇注型聚氨酯弹性体性能的研究   总被引:3,自引:0,他引:3  
采用不同品种的多元醇与异佛尔酮二异氰酸酯(IPDI)反应合成了浇注型聚氨酯弹性体,研究了不同多元醇结构对IPDI型聚氨酯弹性体性能的影响;用红外光谱表征了聚氨酯弹性体的结构,并对其进行了力学性能、动态性能和耐溶剂性能测试。结果表明,聚酯多元醇(Pol-2456)的聚氨酯弹性体力学性能最好;聚醚和聚酯型聚氨酯弹性体在较高温度下tan8值仍然保持在0.4左右,可以作为阻尼材料;端羟基聚丁二烯的聚氨酯弹性体的动态性能最好,峰值为0.715(-60.4℃),-10℃以下,tanδ值基本保持在0.2左右,且具有好的耐溶剂性。  相似文献   

13.
Norbornane diisocyanate (NBDI: 2,5(2,6)-bis(isocyanatomethyl)bicyclo[2.2.1]heptane) is a new commercialized diisocyanate. NBDI-based polyurethane elastomers (PUEs) were prepared from poly(oxytetramethylene) glycol (PTMG), NBDI and 1,4-butanediol (BD) by a prepolymer method. Microphase-separated structure and mechanical properties of the NBDI-based PUEs were compared with general aliphatic and cycloaliphatic diisocyanate-based PUEs. The diisocyanates used were isophorone diisocyanate (IPDI), 4,4′-dicyclohexylmethane diisocyanate (HMDI) and 1,6-hexamethylene diisocyanate (HDI). Regular polyurethanes were also prepared as hard segment models from each isocyanate and BD to understand the feature of each hard segment chain. The HDI-based PUE showed the largest Young's modulus and tensile strength in the four PUEs due to the ability of crystallization of the hard segment component and the strongest microphase separation. HMDI has both properties of aliphatic and cycloaliphatic diisocyanates because of its high symmetrical chemical structure compared with NBDI and IPDI. On the other hand, the NBDI- and IPDI-based PUEs have an inclination to phase mixing, leading to decreased Young's modulus and tensile strength. The NBDI-based PUE exhibited better thermal properties at high temperatures due to stiff structure of NBDI.  相似文献   

14.
Irregular networks based on the condensation reaction of hydroxyl‐terminated poly(dimethylsiloxane) with cross‐linkers were investigated. The networks have excellent damping properties in a wide temperature range utilizing the viscoelastic relaxation of the irregular network with dangling chains. NMR Cross‐link Density Spectroscopy was used to explore the weight fraction of pendant chains and elastic chains in the elastomer. The transverse relaxation time for the elastomer was studied to explore the influence of pendant chains. The effects of the structure of cross‐linkers and the molecular weight of precursors were studied in detail. Elastomers cross‐linked by tetra‐functional cross‐linker (TEOS) have higher damping properties than the elastomers cross‐linked by tri‐functional cross‐linkers (MTMS and OTMS). A damping elastomer based on irregular networks with effective damping (tanδ > 0.3) temperature range of more than 250°C (from lower than ?60°C to 190°C) was prepared. POLYM. ENG. SCI., 56:97–102, 2016. © 2015 Society of Plastics Engineers  相似文献   

15.
Polyurethane elastomers possessing dangling chains were prepared by partial substitution of the multifunctional polyol with a monohydroxyl alcohol in the reaction with an isocyanate terminated prepolymer. The dynamic mechanical spectroscopy showed that created dangling segements resulted in a broader glass-transition region. This indicated material with potentially good energy absorbing properties might be prepared from a ‘dangling polymer’ system. © 1993 John Wiley & Sons, Inc.  相似文献   

16.
Rigid polyurethane (PU) foams were prepared using three North American seed oil starting materials. Polyol with terminal primary hydroxyl groups synthesized from canola oil by ozonolysis and hydrogenation based technology, commercially available soybean based polyol and crude castor oil were reacted with aromatic diphenylmethane diisocyanate to prepare the foams. Their physical and thermal properties were studied and compared using dynamic mechanical analysis and thermogravimetric analysis techniques, and their cellular structures were investigated by scanning electron microscope. The chemical diversity of the starting materials allowed the evaluation of the effect of dangling chain on the properties of the foams. The reactivity of soybean oil-derived polyols and of unrefined crude castor oil were found to be lower than that of the canola based polyol as shown by their processing parameters (cream, rising and gel times) and FTIR. Canola-PU foam demonstrated better compressive properties than Soybean-PU foam but less than Castor-PU foam. The differences in performance were found to be related to the differences in the number and position of OH-groups and dangling chains in the starting materials, and to the differences in cellular structure.  相似文献   

17.
Two kinds of diols containing 1,2,3-triazole units were synthesized through the azide-alkyne cycloaddition reaction between propargyl alcohol and 1,4-diazidobutane. One of the diols, (butane-1,4/1,5-diylbis[1H-1,2,3-triazole-1,4/1,5-diyl])dimethanol (BDTDO-1), containing 1,4/1,5-disubstituted 1,2,3-triazole regioisomers, was directly prepared under thermal condition without Cu(I) catalyst. The other diol, (butane-1,4-diylbis[1H-1,2,3-triazole-1,4-diyl])dimethanol (BDTDO-2), containing 1,4-disubstituted 1,2,3-triazoles, was prepared by Cu(I) catalyzed click chemistry. Then, two kinds of 1,2,3-triazole modified polyurethane elastomers (PUEs) were prepared from the reaction of 4,4′-methylenebis(phenyl isocyanate) and poly(tetramethylene ether) glycol, with BDTDO-1 or BDTDO-2 as the chain extender (CE). It was found that the introduction of 1,2,3-triazoles and their substitution positions had significant influences on the hydrogen bonding, thermal and mechanical properties of PUEs. Compared with the PUE prepared from 1,4-butanediol as the CE, the PUE containing symmetric 1,4-disubstituted 1,2,3-triazoles units in the main chains shows higher values of hydrogen bonding, physical crosslinking density, Young's modulus, tensile strength and melting temperature, while lower glass transition temperature, resulting from the rigid structure and the ability to form more hydrogen bonds. However, the introduction of asymmetric 1,4/1,5-disubstituted 1,2,3-triazole moieties decreases the values of hydrogen bonding, thermal and mechanical properties of PUE appreciably due to the destruction of the ordered structure of the hard segments.  相似文献   

18.
This article for the first time reveals the impact of the damping property of materials on its sand-fixing durability. Based on the turbulence of wind, it could be regarded as a kind of periodic mechanical force. So, when polymers are used to fix sand, they would constantly perceive a periodic force of wind. And, this force would give rise to yielding fracture and fatigue of polymer, so that the sand-fixing durability of material could be weakened significantly. To impair the periodic force of wind and extend the durability of sand-fixation polymer materials, we, for the first time, introduce the designing principle of macromolecular damping material, that can transform external mechanical force into own thermal energy, into the preparation of sand-fixing materials. In this work, poly(vinyl acetate) (PVAc) emulsions with different dangling chain have been synthesized successfully in order to improve their damping properties. The effects of the prepared PVAc with gradually growing dangling chain length have been investigated on their damping properties, on the sand stabilization strengths and sand-fixing durability. And the relationship between the damping property and the sand-fixing property of PVAc was built by simulating wind tunnel test. The experimental results show that, introducing the dangling chain could significantly improve the damping temperature range and extend the anti-wind erosion time of PVAc. It has to be noticed that, introducing the dangling chain, will provide a double effects for the sand stabilization strength of materials, i.e., it can improve both the flexibility of the side-chain and the internal friction of the molecular chains. Wind tunnel test verified that introducing the dangling chain can raise the damping performance of material and convert more periodic force of wind into the friction heat of molecular chain, and thus impair the damage of wind on the materials and improve their anti-wind erosion properties. These findings suggest that the damping material applied in sand fixation is a bright idea and successful method for improving the sand-fixing durability. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47208.  相似文献   

19.
NDI型聚氨酯弹性体动态生热性能研究   总被引:1,自引:0,他引:1  
采用1,5-萘二异氰酸酯(NDI)、己二酸乙二醇丙二醇酯二醇(PEPA)等原料合成了一种新型耐热的聚氨酯弹性体。通过动态力学性能测试(DMA)和压缩疲劳温升试验,对NDI型聚氨酯弹性体的动态性能进行了分析研究,并与TDI型聚氨酯弹性体进行了比较。结果表明,NDI型聚氨酯弹性体损耗因子小、储能模量大、阻尼小、动态生热低,耐热性能比TDI型聚氨酯弹性体好。  相似文献   

20.
以锑类化合物(乙二醇锑或氧化锑)作为PUE(聚氨酯弹性体)的改性剂,探讨了改性剂含量对PUE的合成工艺、性能及结构等影响。结果表明:随着体系中乙二醇锑含量的不断增加,PUE复合材料的密度、硬度和拉伸强度逐渐增大,但断裂伸长率呈先升后降态势,PUE基体中乙二醇锑的结晶结构遭到破坏;随着氧化锑含量的不断增加,PUE复合材料的密度、硬度和拉伸强度缓慢上升,而断裂伸长率显著下降,氧化锑的结晶结构依然存在;当乙二醇锑和氧化锑含量相同时,乙二醇锑对PUE表现出较高的催化活性,对PUE复合材料的性能影响较大;乙二醇锑对PUE复合材料的阻燃效果略逊于氧化锑。  相似文献   

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