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1.
 Organo-soluble fluorinated polyimides were synthesized by the polycondensation of a new aromatic diamine -bis(4-amino-3,5-dimethylphenyl)-4′-fluorophenyl methane with several aromatic dianhydrides. The one-step polymerization procedure was conducted at 180℃ in m-cresol, producing the polyimides with inherent viscosities of 0.680.76 dL•g1. The polyimides could be soluble not only in polar aprotic solvents, such as N-methyl-2-pyrrolidinone, and N,N-dimethylacetamide, but also in common organic solvents, such as chloroform, cyclopentanone, m-cresol and so on. The polyimide films show excellent transparency with the UV-Vis cut-off lengths of 310360 nm and light transmittances of higher than 80% in the visible region. In addition, the polyimides exhibit good thermal stability with an initial decomposition temperature (Td) higher than 530℃ and have more than 60% of residual weight retentions at 700℃.  相似文献   

2.
An aromatic diamine monomer,4,4'-bis(3-amino-5-trifluoromethyl phenoxy)-biphenyl (TFBPDA),wassynthesized via the nucleophilic displacement reaction of 3,5-dinitrobenzotrifluoride and 4,4'-biphenol.The monomer wasreacted with various aromatic dianhydrides via the high temperature polycondensation procedure to provide a series ofpolyimides.The polyimides,PI-1 to PI-4,show good solubility not only in aprotic solvents,such as N-methyl-2-pyrrolidinone and N,N-dimethylacetamide,but also in many common solvents,such as m-cresol,chloroform andcyclopentanone.PI-4,derived from 4,4'-(hexafluoroisopropylidene)diphthalic anhydride and TFBPDA,was even soluble intoluene.Moreover,PI films exhibit good thermal stability,outstanding transparency in the visible light region and acceptablemechanical and electrical properties.The excellent combined properties of the polyimides make them as a good candidate forfabricating microelectronics.  相似文献   

3.
A kind of highly organsoluble polyimide and copolyimides were successfully synthesized from bicyclo(2.2.2)-oct- 7-ene-2,3,5,6-tetracarboxylic dianhydride (BCDA), the commercial diamine 4,4'-methylenedianiline (MDA) and the designed diamine 4,4'-methylenebis-(2-tert-butylaniline) (MBTBA). The polyimide from BCDA and MBTBA is highly soluble in conventional low boiling point solvents (such as chloroform, tetrahydrofuran) at room temperature. But the solubility of the copolyimides in conventional solvents decreased with the molar ratio of MBTBA and MDA decreased. When the molar ratio of MBTBA and MDA was larger than 7/3, the copolyimides can be soluble in low boiling point solvents at room temperature to form a transparent, flexible, tough film by solution casting. When the molar ratio of MBTBA and MDA was between 7/3 and 1/9, they can only be soluble in hot dipolar aprotic solvents (such as DMF, NMP etc.) and form films too. The copolyimide was only soluble in m-cresol when the molar ratio of MBTBA and MDA was lower than 1/9. The number-average molecular weights of the soluble copolyimides were larger than 5.8 × 1064 g/mol by GPC and their polydispersity indices were higher than 1.4. Only one glass transition temperature of these copolyimides was detected around 400℃ by DMA. The copolyimides did not show appreciable decomposition up to 430℃ in N2.  相似文献   

4.
The random copolymers of styrene and 2,5-bis[(4-methoxyphenyloxycarbonyl)styrene] (MPCS) with different copolymerization ratio were synthesized by conventional free radical polymerization. The copolymer having high molecular weight was experimentally elucidated using a combination of proton nuclear magnetic resonance spectroscopy and gel permeation chromatography. The liquid crystalline behavior of the copolymer was studied using differential scanning calorimetry, X-ray diffractometry and polarized optical microscopy. It was found that the liquid crystalline behavior was dependent on the content of styrene. Experimental results show that the copolymer could turn into a liquid crystalline phase at about 180℃ when the content of styrene was less than 20%. The mechanical properties of the copolymer were also studied. Preliminary results indicate that the tensile strength decreases while the tensile modulus increases as the content of MPCS is increased.  相似文献   

5.
研究了在硫酸介质中 ,铁 催化抗坏血酸还原 3 ,3′,5 ,5′ 四溴联苯 双 (重氮氨基偶氮苯 )(TBDPBDAA)而褪色的反应及其动力学条件 ,测定了反应级数和表观活化能 ,建立了催化动力学光度法测定痕量铁的新方法。方法的测定范围为 0~ 0 .0 80mg L;测定下限为 4.3× 1 0 - 1 0 g mL。用于测定发样、茶叶、面粉中的痕量铁 ,与电感耦合等离子体原子发射光谱法 (ICP AES)对照 ,结果满意。  相似文献   

6.
以3-氨基-4-酰胺肟基呋咱(AAOF)为原料合成出了含能化合物3-氨基-4-酰氯肟基呋咱(ACOF)。用稀碱3%~5%Na2CO3水溶液处理,ACOF脱去一分子HCl生成不稳定中间体3-氨基-4-氰基呋咱的氧化物(ACFO),随后发生歧化反应,生成3,4-二(氨基呋咱基)氧化呋咱(BAFF)及其异构体3,6-双(3’-氨基呋咱-4-基)-1,4-二氧杂-2,5-二氮杂环己-2,5-二烯(BADDD)。用IR、MS、^1H NMR、^13C NMR和元素分析对ACOF的分子结构进行了表征。分子和晶体结构测试表明,BADDD是一具有新颖化学分子结构的化合物。  相似文献   

7.
(S)-Dimethyl-4, 4‘-dimethoxy-5, 6, 5‘, 6‘-dimethenedioxy-biphenyl-2, 2‘-dicarbonylate was synthesized in reasonable yield through a series of reactions, including chiral oxazolinemediated asymmetric Ullmann coupling, from methyl 2-bromo-5-methoxy-3, 4-methenedioxybenzoate.  相似文献   

8.
以4,4′?二氨基苯磺酰替苯胺(DASA)、1,8?二氨基萘为原料,通过重氮化、偶合反应合成了一种新型可降解绿色环保型偶氮染料—4,4′?二(4,5?二氨基?1?偶氮萘)苯磺酰替苯胺,产品结构经MS、1 H NMR和元素分析进行了表征.对反应条件进行了优化,当反应时间45 min、温度0~5℃及pH为6时,产率可达57...  相似文献   

9.
《中国化学》2006,24(9):1259-1262
Reaction of the oligo(phenylenevinylene) 4,4'-bis(2,5-dimethylstyryl)biphenyl (bdb) with CF3CO2Ag in benzene gave a novel octanuclear sandwich cluster [Ags(bdb)2(C6H6)2(CF3CO2)8]·2C6H6 (1). The clusters are packed on each other through strong n-n interactions to form ^1D 'brick' chains, between which the solvated benzene molecules are located. TG analysis showed that cluster 1 could completely liberate the guest benzene molecules at 105℃ and the coordinated benzene molecules at 180 ℃. In solid state, cluster 1 exhibits fluorescence, and the emission band is red-shifted compared with that of free ligand bdb.  相似文献   

10.
介绍了新显色剂2 (3 羧基 2,4,5 三氮唑偶氮) 5 乙酰氨基苯酚(CTZAAP)与铜的显色反应研究及应用,建立了测定铜的新方法。在pH5.5的HOAc NaOAc缓冲溶液中,该试剂与铜(Ⅱ)形成1∶1红色稳定络合物,λmax为561.2nm,铜(Ⅱ)量在0~1.0μg·ml-1范围内符合比耳定律,表观摩尔吸光系数为2.16×104L·mol-1·cm-1。其他金属离子共存时,不经预分离可直接测定食品及环境水样中的微量铜(Ⅱ),操作简便,结果满意。  相似文献   

11.
介绍新水溶性显色剂2-(3-羧基-2,4,5-三氮唑偶氮)-5-二甲氨基苯磺酸(CTZAMBS)与镍的显色反应研究及应用,建立了测定镍的新方法。在pH=7.26的NaH_2PO_4-Na_2HPO_4缓冲溶液中,该试剂与镍按1:1的比例形成稳定的紫红色络合物,λ_(max)为540.6nm,镍的浓度在0-1.0μg/L范围内符合比耳定律,表观摩尔吸光系数为2.86×10~4L/(mol·cm)。在氟化铵及硫脲的存在下,可直接测定镁和铝合金中的微量镍。  相似文献   

12.
2,5—二取代—l,3,4—噁二唑化合物具有消炎,抗菌,调节植物生长,杀虫门等广泛的生物活性。作者曾研究了取代胺在2—甲磺酰基—5—(2—苯基—4—喹啉基)—1,3,4—噁二唑化合物环2—位上的亲核加成消去反应,制得了一系列新的2—取代基—5—(2—苯基—4—喹啉基)—1,3,4—噁二唑衍生物,并发现它们具有一定的抗菌活性。在此基础上,我们又研究了含氮亲核试剂在 2—甲磺酰基—5—(3,4,5—三甲氧基苯基)—1,3,4,—噁二唑环2—位上的亲核加成消去反应,制得一系列新的2—取代基—5—(3,4,5—三甲氧基苯基)—1,3,4—噁二唑衍生物。作者用3,4,5—三甲氧基苯甲酰肼在KOH催化下与CS_2反应得到2—巯基—5—(3,4,5—三甲氧基苯基)—l,3,4—噁二唑1,1在NaOH溶液中与Me_2S0_4作用得到2—甲硫醚—5—(3,4,5—三甲氧基苯基)—1,3,4—噁二唑2,2在冰醋酸水溶  相似文献   

13.
研究了铁(Ⅲ)催化H2O2氧化2-(5-羧基-1,3,4-三氮唑偶氮)-5-二乙氨基苯甲酸(CTZDBA)的褪色反应及其动力学条件,褪色反应程度与铁(Ⅲ)量在一定范围内呈线性关系,建立了测定痕量铁(Ⅲ)的催化动力学光度法。在pH4.0的HAc-NaAc缓冲溶液介质中,褪色体系的最大吸收波长581nm,Fe(Ⅲ)的质量浓度在0.0008~0.04μg/mL范围内符合线性关系,回归方程为ΔA=25.325ρ-8.02×10-3(ρ:μg/mL),相关系数为0.9977,检出限3.78×10-10g/mL,方法用于头发和面粉中痕量铁的测定,结果与AAS测定结果相符。  相似文献   

14.
本文研究了Gd(Ⅲ)对Dy(Ⅲ)-1,5-双(1′-苯基-3′-甲基-5′-氧代吡唑-4′-基)戊二酮-[1,5](BPMPPD)-溴化十六烷基三甲胺(CTMAB)体系的荧光增强作用。加入Gd(Ⅲ),不仅使Dy(Ⅲ)-BPMPPD-CTMAB体系的荧光强度明显增强,而且大大提高了该体系的稳定性和抗干扰能力。该体系中Dy(Ⅲ)浓度在4.0×10~(10)~1.0×10~(-6)mol/L范围内与其荧光强度呈线性关系,检测限为8.0×10~(-11)mol/L。该体系用于合成样品中微量Dy(Ⅲ)的测定,取得了满意的结果。  相似文献   

15.
黄应平  张华山 《分析化学》2000,28(2):164-167
介绍了新试剂2,3,7三羟基-9-[3,5-二溴-4-(2,4二羟基)苯偶氮]苯基荧光酮(DBARPF)的合成。通过元素分析、红外光谱和紫外光谱等方法测试,确定了该试剂的组成和结构。研究了试剂与一些金属离子显色反应的光度性质,建立了光度法测定微量锆(Ⅳ)的新方法。在0.6mol/L盐酸介质中,阳离子表面活性剂CTMAB存在下,锆(Ⅳ)与DBARP形成稳定的1:4水溶性络合物,λmax=538nm,λ538nm为1.78×105L·mol-1·cm-1。锆(Ⅳ)含量在0~400μg/L范围服从比尔定律。拟定方法用于铝合金样品中微量锆(Ⅳ)的测定,获得满意的结果。  相似文献   

16.
本文研究了新试剂4,4′-二[3-(4-苯基-2-噻唑基)三氮烯基]联苯(BPTTBP)与阳离子表面活性剂溴化十六烷基吡啶(CPB)和溴化十六烷基三甲基铵(CTMAB)的显色反应。结果表明,在NaOH碱性介质中,试剂BPTTBP分别与CPB和CTMAB形成紫色离子缔合物,最大吸收波长为607nm。试剂BPTTBP与CPB和CTMAB的缔合比均为1∶1,其表观摩尔吸光系数分别为2.46×104L·mol-1·cm-1和1.82×104L·mol-1·cm-1,CPB和CTMAB含量在0~1.0×10-5mol·L-1范围内符合比耳定律。方法直接用于废水中微量CPB和CTMAB的测定,结果满意。  相似文献   

17.
18.
2,6-二氯-4-三氟甲基苯胺经重氮化后与2,3-二氰基丙酸酯反应合成了1-(2,6-二氯-4-三氟甲基苯基)-3-氰基-5-氨基吡唑(1), 1与乙酸酐、顺丁烯二酸酐、苯甲酰氯反应得到1的乙酰胺2a、顺丁烯酰亚胺2b和苯甲酰胺2c. 通过元素分析、红外光谱、核磁共振氢谱、核磁共振碳谱、质谱等手段对其结构进行了表征. 用X射线单晶衍射测定了化合物2a, 2b2c的晶体结构. 2a属于单斜晶系, C2/c空间群, 晶胞参数a=1.88282(6) nm, b=0.86541(3) nm, c=1.90766(6) nm, β=95.5830(10)°, V=3.09362 nm3, Z=8, R=0.064, wR=0.170. 2b属于单斜晶系, P21/n空间群, 晶胞参数 a=1.28261(10) nm, b=0.89942(7) nm, c=1.46896(12) nm, β=104.217(1)°, V=1.6427(2) nm3, Z=4, R=0.055, wR=0.165. 2c属于三斜晶系, P-1空间群, 晶胞参数a=0.84613(11) nm, b=0.98923(13) nm, c=1.14305(15) nm, β=96.002(2)°, V=0.9326 nm3, Z=2, R=0.0684, wR=0.1795.  相似文献   

19.
通过Stille反应合成了3′,4′-亚乙基二氧-2,2′:5′,2″-三噻吩(TET),并以其作为单体,采用化学氧化原位聚合方法在碳纳米管(CNT)的表面包覆新型聚(3′,4′-亚乙基二氧-2,2′:5′,2″-三噻吩)(PTET),制备了PTET-CNT纳米复合材料.通过TEM、SEM和IR对其进行了表征,并利用循环伏安、交流阻抗、恒电流充放电等电化学测试方法,比较研究了复合材料以及碳纳米管在0.1 mol/L四乙基四氟硼酸铵(Et4NPF4)的乙腈溶液中的电化学行为.实验结果表明,在电流密度为3 mA/cm2时,PTET-CNT复合材料的比电容为86 F/g,比原碳纳米管比电容20 F/g提高了3.3倍.基于这种复合材料的电容器的能量密度达到2.02 Wh/kg.  相似文献   

20.
2,6-二氯-4-三氟甲基苯胺经重氮化后与2,3-二氰基丙酸酯反应合成了1-(2,6-二氯-4-三氟甲基苯基)-3-氰基-5-氨基吡唑(1), 1与苯磺酰氯、对甲基苯磺酰氯、甲基磺酰氯反应, 得到1的苯磺酰胺2a、对甲基苯磺酰胺2b和双甲基磺酰胺2c. 通过元素分析、红外光谱、核磁共振氢谱、核磁共振碳谱、质谱等手段对其结构进行了表征. 用X射线单晶衍射测定了化合物1, 2a2c的晶体结构. 1属于正交斜方晶系, Pbca空间群, 晶胞参数 a=1.61739(7) nm, b=1.62480(7) nm, c=3.10857(13) nm, =90, V=8.1691 nm3, Z=24, R=0.1089, wR=0.2545. 2a属于单斜晶系, C2/c空间群, 晶胞参数 a=3.35144(18) nm, b=0.97948(5) nm, c=2.44717(12) nm, β=102.460(1), V=7.8440(7) nm3, Z=8, R=0.1831, wR=0.2600. 2c属于三斜晶系, P-1空间群, 晶胞参数 a=0.84681(7) nm, b=0.89652(83) nm, c=1.43497(12) nm, α=75.198(2), β=87.918(1), γ=65.395(1), V=0.9546 nm3, Z=2, R=0.049, wR=0.135.  相似文献   

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