首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
Novel aromatic polyamides were prepared from aromatic diamine containing 4,5-imidazolediyl unit, either by low temperature solution polycondensation or by direct polycondensation. Used diamines were 4,5-bis(4-aminophenyl)-2-phenylimidazole 1, 4,5-bis[4-(4-aminophenyl)]-2-(4-methylphenyl)imidazole 2 and 4,5-bis[4-(4-aminophenoxy)phenyl]-2-phenylimidazole 3. The obtained aromatic polyamides were produced with moderate to high inherent viscosity and soluble in polar aprotic solvents such as N,N-dimethylacetamide (DMAc), 1-methyl-2-pyrrolidone (NMP), N,N-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO). Thermogravimetric analysis showed those polymers were stable up to 422°C in nitrogen atmosphere. The glass transition temperature (T g)s of the polymers derived from diamine 3 were in the range between 243 and 275°C, and these values were approximately 120–160°C lower than those analogue polyamide I series containing no phenoxy units. The properties of polyamide I series are also compared with those of analogue polymers that order of aromatic nuclei and amide linkage is reversible.  相似文献   

2.
α,β-不饱和酮(1a~1e)与邻氨基苯硫酚反应, 得到含2-苯基-1,2,3-三唑基1,5-苯并硫氮杂(艹/卓)(2a~2e), 然后以此化合物为原料同1,3-偶极子氧化腈"现场"发生1,3-偶极环加成, 合成出一系列含2-苯基-1,2,3-三唑基的1,2,4-(口恶)二唑并合的1,5-苯并硫氮杂衍生物(3a~3j). 产物经元素分析、 IR、 1H NMR及MS加以确证.  相似文献   

3.
标题化合物C_20H_18N_2是由2-氰-3-苯基-3-(1-萘酮-2-基)丙腈在低价钛试剂作用下还原成环而得。结构通过单晶X-射线衍射分析确定,其晶体属于三斜晶系,空间群P, a = 9.169(2), b = 9.520(2), c = 10.276(2) , a = 91.09(1), = 107.95(1), = 111.05(2), V = 787.8(3),Mr = 286.36 ?, Dc = 1.207 g/cm3, Z = 2, m(MoKa) = 0.071 mm-1, F(000) = 304, R = 0.0399, wR = 0.1008。单晶X-射线分析表明,五员环(C(7)~C(11))采用信封式构象,而六员环(C(10)~C(15))则采用半椅式构象,同时,分子间氢键作用形成二聚体。  相似文献   

4.
以改进的溶胶-凝胶法制备了Sb2O3/TiO2纳米复合物,用扫描电镜、X射线粉末衍射、傅立叶红外光谱、紫外-可见光谱以及荧光等测试技术对产物进行了分析和表征.结果表明:所得纳米复合物颗粒分散均匀,具有锐钛矿相结构,平均粒径约为10nm.还研究了所得产物的光催化性质、电化学性质及电化学发光行为.结果表明:Sb2O3的掺入可以提高TiO2的光催化效果,当反应物中m(Sb2O3)/m(TiO2)=10%时,所得纳米复合物对亚甲基蓝和罗丹明B的光催化效果最好.  相似文献   

5.
采用水热合成方法,在特定的反应条件下合成了具有锐钛矿相结构的TeO2/TiO2纳米复合物,探讨了产、物的形成机理和影响因素;用透射电镜、X射线粉木衍射、紫外-可见光潜、荧光光谱以及循环伏安等手段对产物的结构和性质进行了分析和表征。  相似文献   

6.
1 INTRODUCTION Pyrrole and its derivatives have attracted much attention due to their chemical properties as well as biological activities[1]. They have been widely used as the materials to produce pharmaceutical, essences, biochemicals, etc. It has been found that a great deal of pyrrole derivatives present bioactivities, such as antitumor and antiviral activities[2~5]. Thus, due to the interest in exploring the syntheses of potential bioactive materials which contain pyrrole ring andna…  相似文献   

7.
Novel polyamides bearing calix[4]arene and triazole units, polytriazolecalixamides (PTCAs), were prepared by direct polycondensation of a new bistriazole substituted dicarboxylic acid derivative of calix[4]arene with commercial diamines. The polytriazolecalixamides were obtained in high yields and possessed inherent viscosities in the range of 0.42–0.59 dl/g. These polytriazolecalixamides were readily soluble in polar aprotic solvents such as NMP, DMSO, DMAc at room temperature and in THF by heating. Nanocrystalline structures were determined by XRD patterns and confirmed by DSC as well as TEM and AFM imaging techniques. The photophysical study was performed by UV-absorption spectroscopy and maximum wavelength for each polymer specified in details. Glass transition temperatures were between 134 and 154°C. Thermogravimetric analysis showed that these polyamides displayed high thermal stability ranged from 273 to 312°C at the point of 10% weight loss, and char yields were about 51.4–67.4% at 600°C in nitrogen. All of these nanocrystalline polycalixamides showed promising sorption properties towards transition metal ions such as Cu2+, Cr2+, Co2+, Cd2+ and especially Pb2+ in solid-liquid extraction which fulfill our needs in synthesizing novel high performance polyamides.  相似文献   

8.
本文报道了荣光试剂3-苯基-5-苯甲酰基-2-疏代-4-噻唑啉酮(PBTT)的合成。产品经拉层桥提纯,用元素分析、IR、1HNMR和MS确证了其结构;研究了它的荧光性质。在PH5.6时,与痕量镜(Ⅲ)形成络合物。且在λex/λem=305nm/405nm产生强荧光。测定了人工合成样品中的铥,结果比较满意。  相似文献   

9.
合成了化合物1-苯基-3-甲基-4-苯甲酰基-5-吡唑啉酮(HPMBP)缩甘氨酸甲酯,用红外光谱、核磁共振谱和元素分析等方法进行了表征,用X射线衍射方法测定了其晶体结构.晶体学参数如下:三斜晶系,空间群为P1, a=0.9403(3) nm, b=0.9884(3) nm, c=1.0127(3) nm, α=86.666(7)°, β=89.827(6)°, γ=73.951(6)°, V=0.9029(5) nm3, Z=2, Dc=1.285 Mg·m-3, μ=0.088 mm-1, F(000)=368.最终偏离因子R1=0.0452, wR2=0.0889.  相似文献   

10.
1 INTRODUCTIONNeonicotinoids[1~2]areanovelanddistinctclassofinsecticides.Theycombineselectiveactivityagainstinsectswithafavourablesafetyprofile.Neonicotinoidsactatthenicotinicacetylcholinereceptor(nAChR)[3~4].Sincethefirstneonicotinoid,imi-dacloprid(IMI)1wasintroducedtothemarketbyBayerin1991,alotofitsanalogswerereported.Thesecompoundshavethesamestructuralunit,asshowedindashedlineareainIMI.AccordingtothemodelproposedbyYamamotoetal[5],thedistancebetweenthetwonitrogenatomsofIMIisthe…  相似文献   

11.
本文以脲为沉淀剂,通过化学沉淀法成功实现了锐钛矿型二氧化钛壳层在空心玻璃微珠表面的可控组装,从而制备出玻璃/二氧化钛核壳空心微球,并通过XRD、SEM、EDX和拉曼光谱对其结构、形貌、粒径、壳厚和化学组成进行了表征.提出了二氧化钛在空心玻璃微珠表面的定向生长的可能机制和形成过程.  相似文献   

12.
A new energetic material, 4,5-dimethoxy-2-(dinitromethylene)imidazolidine(DMDNI), was synthesized by the reaction of 4,5-dihydroxyl-2-(dinitromethylene)-imidazolidine(DDNI) and methanol, and structurally characterized by single crystal X-ray diffraction. DMDNI crystallized in triclinic space group P, with crystal data a=0.4324(4) nm, b=1.3599(11) nm, c=1.7503(14) nm, α=77.406(14)°, β=84.494(15)°, γ=87.976(14)°, V=0.9997(14) nm3, Z=4, μ=0.140 mm-1, F(000)=488, Dc=1.556 g/cm3, R1=0.0773 and wR2=0.1574. Thermal decomposition of DMDNI was studied, and its thermal decomposition process was divided into two stages. The first stage was a mel- ting process and the second stage was an exothermic decomposition process. The enthalpy, apparent activation energy and pre-exponential constant of the exothermic decomposition reaction are -491.5 J/g, 142.3 kJ/mol and 1014.24 s-1, respectively. The critical temperature of thermal explosion is 162.47℃. DMDNI has a lower thermal stability than DDNI but it is close to that of 4,5-diacetoxyl-2-(dinitromethylene)-imidazolidine(DADNI).  相似文献   

13.
利用简单的水热法以及后续热处理, 将钴酸镍纳米花成功生长在活性炭纤维支架上. 场发射扫描电镜(FESEM)及透射电镜(TEM)结果表明, 纳米花是由纳米针自组装而成, 而纳米针呈多孔结构. 这种三维复合多级结构非常有利于电解质离子的渗透和电子的传输. 将该多孔钴酸镍纳米花/活性炭纤维布作为工作电极, 表现出优良的电容性能. 在1 A·g-1时, 比电容高达1626 F·g-1; 在10 A·g-1时, 电容保持率为65%, 具有超高的电容值和优异的倍率特性.  相似文献   

14.
林振光  庄鸿辉 《结构化学》1996,15(3):199-204
环己酮与硫代碳酰肼在不同介质中的反应,合成出两个不同的环己烷螺含氮杂环化合物。经X-射线结构分析确定它们分别为1,2,4,5-四氮螺[5,5]十一烷-3-硫酮,C_7H_(14)N_4S(Ⅰ)和1,2,4,-三氮螺[4,5]癸-1-烯-4-氨基-3-硫酮。C_7H_(12)N_4S_x(S_x=0.8S+0.2O)(Ⅱ)。晶体学参数分别为(Ⅰ):P2_1/c,a=12.026(4),b=26.817(6),c=12.042(3),β=115.94(2)°,Z=4,V=933.4(10),M_r=186.28;(Ⅱ):P2_1/m,a=6.595(7),b=6.817(6),c=10.572(6),β=106.3(1)°,V=456(1),Z=2,M_r=181.05。最终一致因子分别为R=0.054,R_w=0.065和R=0.089,R_w=0.096。两个化合物中,环己烷都为椅式构型,它与其螺联的6员氮杂环,5员氮杂环的最小二乘平面间的夹角分别为68.94和90°。并对合成反应途径作了初步讨论。  相似文献   

15.
利用硅铝无定形结构作为保护层的银纳米颗粒在杀菌和催化领域具有重要应用. 银纳米颗粒的形貌控制是其优异性能的重要保证, 尤其是具有规则结构的银纳米颗粒的合成一直是该领域的难点. 本文以亚稳态结构的硅铝分子筛作为模板, 在室温条件下采用离子交换方法, 通过调整银离子的含量和离子交换时间, 控制银在分子筛中的分布和含量, 在还原剂N(C2H5)3存在下, 通过微波还原反应获得了不同银/硅铝无定形结构比例的复合材料. 透射电子显微镜测试结果表明, 不同比例的前驱体经微波法还原后, 小尺寸的银纳米颗粒可以分布在无定形的硅铝基质中; 当增大银的比例后, 银纳米颗粒则出现项链式结构, 并且由无定形硅铝薄层链接并包裹. 这类结构既具有银纳米颗粒的催化性能, 同时又在硅铝薄层的保护下表现出良好的稳定性, 在杀菌和催化领域具有广泛的应用前景.  相似文献   

16.
以水杨醛与1,2-二溴乙烷为反应物, 乙腈为溶剂, 在无水K2CO3存在下合成了2-溴乙氧基水杨醛(1), 1和二-(1,3-二硫杂环戊烯-2-硫酮-4,5-二硫)合锌酸四乙基铵盐在乙腈中回流, 得到新型的四硫富瓦烯(TTF)前体(2). 在Hg(OAc)2存在下, 2可转化为4,5-二[2-(邻甲酰苯氧基)乙硫基]-1,3-二硫环戊烯-2-酮(3), 其结构经1H NMR, FT-IR, 元素分析和单晶X射线衍射分析得到确证.  相似文献   

17.
中空Fe203/G-NS纳米复合材料的制备和储锂性能   总被引:1,自引:0,他引:1  
以三氯化铁和氧化石墨烯(Graphite oxide,GO)为原料,采用水热法一步合成了中空Fe2O3/石墨烯(Graphene nanoslheet,GNS)纳米复合材料.研究结果表明,Fe2O3/GNS纳米复合材料的形成是由于Fe3+催化氧化GO中的羧基等官能团释放出CO2,并以原位形成的CO2气泡为模板形成了中空...  相似文献   

18.
合成了2例基于2-吡啶甲酸(2-PA)和Keggin类型[SiW12O40]4-、[PMo12O40]3-多酸单元的有机-无机杂化材料:H2[(CH34N]6[Cu(2-PA)2(SiW12O402](1)和(H3O)[Cu6(2-PA)9(PMo12O40)(NO3)](2),并用红外光谱以及X射线衍射对其进行了表征。单晶衍射结构分析表明化合物1为单斜晶系,空间群为P21/c,不对称单元中包含1个二价铜离子、2个2-吡啶甲酸配体以及2个Keggin类型[SiW12O40]4-多酸单元并组成零维结构。循环伏安测试表明化合物1在扫速为100 mV·s-1时,3组半波电位分别为-270、-516、-708 mV。化合物2为三方晶系,空间群为R3c,不对称单元中包含2个晶体学独立的二价铜离子并且具有2种不同的配位模式,是含六核簇合物单元的二维网络结构。  相似文献   

19.
利用类石墨氮化碳(g-C3N4)和亚稳相钙钛氧化物(CaTi2O5)固相法制备C3N4/CaTi2O5复合材料。利用X射线衍射(XRD)、金相显微镜、扫描电子显微镜(SEM)及附带能谱分析仪(EDS)和N2吸附-脱附对样品的显微结构和比表面积进行检测分析,并用紫外-可见吸收光度计(UV-Vis)测试了样品的光吸收性能,研究C3N4与CaTi2O5物质的量之比(nC3N4/nCaTi2O5)对C3N4/CaTi2O5复合样品的物相结构和微观形貌的影响,同时考察C3N4/CaTi2O5复合样品在可见光照射下光催化降解罗丹明染料效果。实验结果表明:相比纯C3N4和CaTi2O5样品,C3N4/CaTi2O5复合样品在可见光下具有较高的光催化性能,随着nC3N4/nCaTi2O5增加,样品的光催化降解率随之增加而后降低,当nC3N4/nCaTi2O5=1:1时,样品的光催化降解率达到最大值99.5%,并且循环重复利用5次后,样品的光催化剂降解率仍几乎保持不变。复合样品光催化性能提高主要归因于复合能级结构有效地抑制了电子和空穴复合所致。  相似文献   

20.
利用类石墨氮化碳(g-C_3N_4)和亚稳相钙钛氧化物(CaTi_2O_5)固相法制备C_3N_4/CaTi_2O_5复合材料。利用X射线衍射(XRD)、金相显微镜、扫描电子显微镜(SEM)及附带能谱分析仪(EDS)和N2吸附-脱附对样品的显微结构和比表面积进行检测分析,并用紫外-可见吸收光度计(UV-Vis)测试了样品的光吸收性能,研究C_3N_4与CaTi_2O_5物质的量之比(nC_3N_4/nCaTi_2O_5)对C_3N_4/CaTi_2O_5复合样品的物相结构和微观形貌的影响,同时考察C_3N_4/CaTi_2O_5复合样品在可见光照射下光催化降解罗丹明染料效果。实验结果表明:相比纯C_3N_4和CaTi_2O_5样品,C_3N_4/CaTi_2O_5复合样品在可见光下具有较高的光催化性能,随着nC_3N_4/nCaTi_2O_5增加,样品的光催化降解率随之增加而后降低,当nC_3N_4/nCaTi_2O_5=1∶1时,样品的光催化降解率达到最大值99.5%,并且循环重复利用5次后,样品的光催化剂降解率仍几乎保持不变。复合样品光催化性能提高主要归因于复合能级结构有效地抑制了电子和空穴复合所致。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号