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1.
聚合物材料结晶度(上)   总被引:7,自引:1,他引:6  
本文介绍了结晶度概念及IUPAC高分子专业委员会最近有关结晶度各述语的一些规定,几种常用的结晶度测定方法,如X射线衍射、量热法、密度测量、红外光谱法等,对X射线衍射方法作了重点叙述.  相似文献   

2.
共轭聚合物发光和光伏材料研究进展   总被引:5,自引:1,他引:4  
聚合物光电功能材料与器件因其广阔的应用前景,1990年以年来吸引了世界各国学术界的广泛关注和兴趣.聚合物光电子器件主要包括聚合物电致发光二极管、聚合物场效应晶体管和聚合物太阳能电池等,其使用的关键材料是共轭聚合物光电子材料,包括共轭聚合物发光材料、场效应晶体管材料和光伏材料等.本文主要对共轭聚合物电致发光材料和光伏材料的研究进展进行综述,介绍了这些聚合物材料的种类、结构和性质以及在聚合物电致发光器件和聚合物太阳能电池中的应用.并讨论了当前共轭聚合物光电子材料中的关键科学问题和今后的发展方向.  相似文献   

3.
聚合物太阳电池因其结构简单、成本低、重量轻和可制成柔性器件等突出优点,近年来受到广泛关注,成为发展绿色可再生能源的重要方向。聚合物太阳电池中的给体和受体光伏材料是决定器件性能的关键,本文综述了共轭聚合物给体和富勒烯受体光伏材料的最新研究进展,并在共轭聚合物给体材料中对聚噻吩衍生物以及窄带隙D-A共聚物进行了重点介绍。同时讨论了薄膜优化和器件稳定性,最后从提高电池效率的几个方面展望了聚合物太阳电池的发展方向。  相似文献   

4.
综述近年来光折变聚合物的材料的研究现状,着重介绍光折变聚合物材料的化学结构,组成及光折变性能。简单分析当前研究工作所面临的问题。  相似文献   

5.
共轭聚合物材料及电致发光器件   总被引:5,自引:0,他引:5  
共轭聚合物是一种极有应用前景的有机半导体材料,本文综述其研究进展,包括典型共轭聚合物材料PPV、PT、PF等及PPP的工作原理,发展前景和存在的问题。  相似文献   

6.
高聚物的热传导性质   总被引:7,自引:0,他引:7  
对聚合物固体、熔体和溶液的传导性质分别进行了论述,介绍了各控制因素对它们热传导的影响,阐述了研究聚合物热传导性质今后的发展方向。  相似文献   

7.
耐高温梯形聚甲基倍半硅氧烷的合成研究   总被引:19,自引:1,他引:18  
以有机伯胺为胺解剂,与甲基三氯硅烷反应形成梯形结构的“模板”,经水解,缩聚反应,合成了梯形聚甲基倍半硅氧烷,研究了水解温度,溶剂,水与单体的摩尔比,缩聚温度,缩聚时间以及胺的结构对产物性能的影响,获得了最佳的合成条件,产物经热重分析,表明其耐热性能优良,700℃失重率仅为4%。  相似文献   

8.
综述了建国50年来我国乳液聚合合成橡胶、合成树脂及合成聚合物聚液工业从无到有,由小到大,由弱到强的发展历程,介绍了我国乳聚合新产品、新技术的开发以及乳液聚合物与聚合物乳推广应用所取得的伟大成就。  相似文献   

9.
结晶聚合物中间层理论与实验佐证   总被引:3,自引:0,他引:3  
概述了Flory和Yoon由晶格模型出发,从理论上证明了结晶聚合物中间层的存在以及近年来许多学者采用多种实验技术确认中间层存在的事实。  相似文献   

10.
聚合物网络快离子导体成膜后有良好的机械强度、尺寸稳定性,但室温电导率稍偏低。本文通过大单体技术合成兼具优良室温电导率(σ_(298K)=4.8×10~(-5)S·cm~(-1))与机械强度的接枝聚合物网络快离子导体,并研究了网络结构、形态与离子导电性之间的关系。 1 实验部分 1.1 试剂及精制 试剂均为化学纯。分子量为800与2000的聚氧化乙烯(PEO800,  相似文献   

11.
In the title compound, {[Zn(C8H4O5)(C12H8N2)]·H2O}n or {[Zn(OH‐BDC)(phen)]·H2O}n (where OH‐H2BDC is 5‐hydroxy­isophthalic acid and phen is 1,10‐phenanthroline), the Zn atoms are coordinated by two N atoms from the phen ligands and by four O atoms from hydroxy­isophthalate ligands in a highly distorted octahedral geometry, with Zn—O distances in the range 2.042 (4)–2.085 (5) Å and Zn—N distances of 2.133 (5) and 2.137 (5) Å. The {[Zn(OH‐BDC)(phen)]·H2O}n infinite zigzag polymer forms a helical chain of [Zn2(OH‐BDC)2]n units. Face‐to‐face π–π interactions (3.60–3.75 Å) occur between two phen rings belonging to the same helical chain. Consolidation of the packing structure is achieved by O—H⋯O hydrogen‐bonding interactions between the carboxyl­ate O atoms, the hydroxyl group and the water mol­ecule, forming two‐dimensional sheets.  相似文献   

12.
In the title compound, {[Zn(C8H4O5)(C12H10N2)]·0.5C12H10N2}n or {[Zn(HO‐BDC)(bpe)]·0.5bpe}n [HO‐H2BDC is 5‐hydroxyisophthalic acid and bpe is 1,2‐bis(pyridin‐4‐yl)ethene], the asymmetric unit contains a ZnII atom, one HO‐BDC ligand, one coordinated bpe ligand and half a noncoordinating bpe molecule with crystallographic inversion symmetry. Each ZnII centre is four‐coordinated by two O atoms from two distinct HO‐BDC ligands and two N atoms from two different bpe ligands in a ZnO2N2 coordination environment. The three‐dimensional topology of the title compound corresponds to a fourfold interpenetrating diamondoid coordination polymer network, with the uncoordinated bpe ligands located in the cavities, hydrogen bonded to the main network via the hydroxy group of the HO‐H2BDC ligand.  相似文献   

13.
Three cadmium(II) coordination polymers [Cd(NA)2(H2O)2]n ( 1 ), {[Cd(NA)(phen)(NO3)]·(H2O)1/2}n ( 2 ), {[Cd(NA)(CH3C6H4COO)(H2O)2]·(CH3C6H4COOH)}n ( 3 ) (HNA = nicotinic acid, phen = 1, 10‐phenanthroline) have been synthesized by hydrothermal method. Their single‐crystal structures were determined by X‐ray diffractometry. The absorption, excitation and emission spectra were investigated and all the complexes emit strong fluorescence: λemmax = 544 nm (λex = 492 nm), 1 ; λemmax = 466 nm (λex = 393 nm), 2 ; λemmax = 430 nm (λex = 313 nm), 3 . At room temperature in the solid state the fluorescence lifetimes of the complexes were investigated and the relationships between the spectra were discussed as well as the connections of luminescence and crystal structures.  相似文献   

14.
A novel two‐dimensional (2D) ZnII coordination framework, poly[[μ‐1,3‐bis(2‐methyl‐1H‐imidazol‐1‐yl)benzene](μ‐5‐nitrobenzene‐1,3‐dicarboxylato)zinc(II)], [Zn(C8H3NO6)(C14H14N4)]n or [Zn(NO2‐BDC)(1,3‐BMIB)]n [1,3‐BMIB is 1,3‐bis(2‐methyl‐1H‐imidazol‐1‐yl)benzene and NO2‐H2BDC is 5‐nitrobenzene‐1,3‐dicarboxylic acid], has been prepared and characterized by IR, elemental analysis, thermal analysis and single‐crystal X‐ray diffraction. Single‐crystal X‐ray diffraction analysis revealed that the compound is a new 2D polymer with a 63 topology parallel to the (10) crystal planes based on left‐handed helices, right‐handed helical NO2‐BDC–Zn chains and [Zn2(1,3‐BMIB)2]n clusters. In the crystal, adjacent layers are further connected by C—H…O hydrogen bonds, C—H…π interactions, C—O…π interactions and N—O…π interactions to form a three‐dimensional structure in the solid state. In addition, the compound exhibits strong fluorescence emissions in the solid state at room temperature.  相似文献   

15.
Four ZnII/CdII coordination polymers (CPs) based on 2‐(4‐carboxy‐phenyl)imidazo[4, 5‐f]‐1, 10‐phenanthroline (HNCP) and different derivatives of 5‐R‐1, 3‐benzenedicarboxylate (5‐R‐1, 3‐BDC) (R = NO2, H, OH), [Zn(HNCP)(5‐NO2‐1, 3‐BDC)]n ( 1 ), [Cd(HNCP)(5‐NO2‐1, 3‐BDC)]n ( 2 ), [Zn(HNCP)(1, 3‐BDC)(H2O)2]n ( 3 ), and {[Zn(HNCP)(5‐OH‐1, 3‐BDC)(H2O) · H2O}n ( 4 ) were synthesized under hydrothermal conditions. Compounds 1 – 4 were determined by elemental analyses, IR spectroscopy, and single‐crystal and powder X‐ray diffraction. Compounds 1 and 2 are isomorphous, presenting a 4‐connected uninodal (4, 4)‐sql 2D framework with threefold interpenetration, which are further extended into the three‐dimensional (3D) supramolecular architecture through π ··· π stacking interactions between the aryl rings of 5‐NO2‐1, 3‐BDC. Compared to compound 1 , 3 is obtained by using different reaction temperatures and metal‐ligand ratios, generating a 3D framework with –ABAB– fashion via π ··· π stacking interactions. Compound 4 is a 1D chain, which is further extended into a 3D supramolecular net by hydrogen bonds and π ··· π stacking interactions. The thermogravimetric and fluorescence properties of 1 – 4 were also explored.  相似文献   

16.
In the cobalt(II) coordination polymer poly[[(μ2‐benzene‐1,3‐dicarboxylato){μ2‐1,1′‐[2,2′‐oxybis(ethane‐2,1‐diyl)]di‐1H‐imidazole}cobalt(II)] monohydrate], {[Co(C10H14N4O)(C8H4O4)]·H2O}n, two crystallographically distinct CoII cations are four‐coordinated by N2O2 donor sets in distorted tetrahedral geometries. The CoII centers are connected by benzene‐1,3‐dicarboxylate (m‐BDC) anions, giving two types of linear chains, which are further joined via meso‐helical 1,1′‐[2,2′‐oxybis(ethane‐2,1‐diyl)]di‐1H‐imidazole ligands to yield a thick two‐dimensional slab. The compound displays a two‐dimensional four‐connected 42.63.8 topology, which is unprecedented in coordination polymers.  相似文献   

17.
Six mono/double‐layered 2D and three 3D coordination polymers were synthesized by a self‐assembly reaction of Zn (II) salts, organic dicarboxylic acids and L1/L2 ligands. These polymeric formulas are named as [Zn(L1)(C4H2O4)0.5 (H2O)]n·0.5n(C4H2O4)·2nH2O ( 1 ), [Zn2(L2)(C4H2O4)2]n·2nH2O ( 2 ), [Zn(L1)(m‐BDC)]n ( 3 ), [Zn2(L2)(m‐BDC)2]n·2nH2O ( 4 ), [Zn3(L1)2(p‐BDC)3(H2O)4]n·2nH2O ( 5 ), [Zn2(OH)(L2) (p‐BDC)1.5]n ( 6 ), [Zn2(L1)(p‐BDC)2]n·5nH2O ( 7 ), [Zn2(L2)(p‐BDC)2]n·3nH2O ( 8 ) and [Zn2(L1)(C4H4O4)1.5(H2O)]n·n(ClO4nH2O ( 9 ) [L1 = N,N′‐bis (pyridin‐4‐ylmethyl)propane‐1,2‐diamine, L2 = N,N′‐bis (pyridin‐3‐ylmethyl)propane‐1,2‐ diamine, m‐BDC2? = m‐benzene dicarboxylate, p‐BDC2? = p‐benzene dicarboxylate]. Meanwhile, these polymers have been characterized by elemental analysis, infrared, thermogravimetry (TG), photoluminescence, powder and single‐crystal X‐ray diffraction. Polymers 1–6 present mono‐ and double (4,4)‐layer motifs accomplished by L1/L2 ligands with diverse conformations and organic dicarboxylates, and the layer thickness locates in the range of 5.8–15.0 Å. In three 3D polymers, the L1 and L2 molecules adopt the same cis‐conformations and join adjacent Zn (II) cations together with p‐BDC2? or succinate, giving rise to different binodal (4,4)‐c nets with (4.52.83)(4.53.72) ( 7 ), pts ( 8 ) topology and twofold interpenetrated binodal (5,5)‐c nets with (32.44.52.62)(3.43.52.64) ( 9 ). Therefore, the diverse conformations of the two bis (pyridyl)‐propane‐1,2‐diamines and the feature of different organic dicarboxylate can effectively influence the architectures of these polymers. Powder X‐ray diffraction patterns demonstrate that these bulk solid polymers are pure phase. TG analyses indicate that these polymers have certain thermal stability. Luminescent investigation reveals that the emission maximum of these polymers varies from 402 to 449 nm in the solid state at room temperature. Moreover, 1 , 3 and 5–8 show average luminescence lifetimes from 8.81 to 16.30 ns.  相似文献   

18.
Four new compounds based on H2BDC and PyBIm [H2BDC = 1,4‐benzenedicarboxylatic acid, PyBIm = 2‐(4‐pyridyl)benzimidazole], (PyBIm)(H2BDC)0.5 ( 1 ), Co(PyBIm)2(HBDC)(BDC)0.5 ( 2 ), Ni(PyBIm)2(HBDC)(BDC)0.5 ( 3 ), and Zn(BDC)(PyBIm) · H2O ( 4 ), were synthesized by hydrothermal methods and characterized by X‐ray diffraction. Compound 1 contains two types of hydrogen bonding N–H ··· N and O–H ··· N, which connect the molecules into a two‐dimensional (2D) layer. Complex 2 crystallizes isostructural to 3 in triclinic space group P$\bar{1}$ , in 1D chains. The hydrogen‐bonding interactions between uncoordinated N, N–H and COOH groups in 2 connect the 1D chains into a 2D layer. Complex 4 displays a 1D structure, which is finally extended to a 3D supramolecular framework by hydrogen bonding and π–π packing interactions. The magnetic properties of compounds 2 and 3 were studied as well.  相似文献   

19.
Three new compounds based on H2BDC and PyBImE [H2BDC = 1,4‐benzenedicarboxylatic acid, PyBImE = 2‐(2‐pyridin‐4‐yl‐vinyl)benzimidazole], namely, [Co(PyBImE)(BDC)(H2O)2] ( 1 ), [Co(PyBImE)2(HBDC)(BDC)0.5] ( 2 ), and [(HPyBImE)+ · (BDC)20.5 · (H2BDC)0.5] ( 3 ), were synthesized by hydrothermal methods and characterized by single‐crystal X‐ray diffraction. Compound 1 is a one‐dimensional chain bridged by terephthalate in a bis(monodentate) fashion. In the complex the nitrogen atom from NBIm and the coordination water molecule complete the coordination sphere. In complex 2 , the dinuclear cobalt units are bridged by terephthalate in a bis(bidentate) fashion into a one‐dimensional chain, but different from complex 1 , the nitrogen atom from NPy and the oxygen atom from hydrogenterephthalate complete the coordination sphere. Complex 3 is a co‐crystal with PyBImE and H2BDC in a 1:1 ratio and the transfer of hydrogen atoms leads the complex into a salt. Interesting supramolecular structures are shown due to the hydrogen bonding as well as π ··· π interactions in the three complexes. Thermal and magnetic properties of 1 and 2 were also studied.  相似文献   

20.
Three new coordination compounds, [Pb(HBDC‐I4)2(DMF)4]( 1 ) and [M(BDC‐I4)(MeOH)2(DMF)2]n (M = ZnII for 2 and MnII for ( 3 ) (H2BDC‐I4 = 2, 3, 5, 6‐tetraiodo‐1, 4‐benzenedicarboxylic acid), were synthesized and characterized by elemental analysis, IR spectroscopy, thermogravimetric (TG) analysis, and X‐ray single crystal structure analysis. Single‐crystal X‐ray diffraction reveals that 1 crystallizes in the monoclinic space group C2/c and has a discrete mononuclear structure, which is further assembled to form a two‐dimensional (2D) layer through intermolecular O–H ··· O and C–H ··· O hydrogen bonding interactions. The isostructural compounds 2 and 3 crystallize in the space group P21/c and have similar one‐dimensional (1D) chain structures that are extended into three‐dimensional (3D) supramolecular networks by interchain C–H ··· π interactions. The PbII and ZnII complexes 1 and 2 display similar emissions at 472 nm in the solid state, which essentially are intraligand transitions.  相似文献   

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