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1.
多异氰酸酯交联型二阶非线性光学聚合物中的极化与松弛   总被引:1,自引:1,他引:0  
杨春才  李加 《应用化学》1995,12(3):23-27
通过4,4'-硝基偶氮苯甘油单醚与六亚甲基二异氰酸酯的缩二脲在电场下极化交联反应合成交联型二阶非线性光学聚合物。利用二次谐波和紫外可见吸收光谱对该聚合物的取向及松弛进行了研究。测试了二阶非线性极化率χ^(2)、二阶非线性光学系数d33和电光系数λ33,表明上述极化交联聚合物的d33在10^-8 ̄10^-7esu,在测试时间范围内基本不随时间而衰减。  相似文献   

2.
在有机二阶非线性光学聚合物聚甲基丙烯酸甲酯侧链中引入可交联的蒽基团,合成含蒽基团的甲基丙烯酸甲酯类聚合物。采用紫外-可见光谱法明确蒽基团在薄膜中的光交联时间,利用蒽基团在光照条件下的可控[4+4]环加成交联反应提高聚合物的取向稳定性。差示扫描量热法(DSC)研究结果表明交联反应后聚合物薄膜的玻璃化转变温度提高了约10℃。聚合物在60℃条件下加热220 h后电光系数仍可保持原来的90%左右,交联后的二阶非线性聚合物的取向稳定性明显提升。  相似文献   

3.
采用封管反应的方法,以较高产率(80%以上)合成了一系列含环氧基团的可交联PMMA型和PS型极化聚合物材料,该材料具有很好的成膜性.用DSC和TgA等方法研究了聚合物固化前后的热性能,结果表明,由于聚合物在极化后期经热固化使引入的环氧基团开环交联,聚合物的玻璃化转变温度(Tg)较固化前明显提高30~50K.同时,固化后的聚合物具有较高的热分解温度(Td>543K).对聚合物的二阶非线性光学性质的测试结果表明,在室温下放置100h后,聚合物的电光系数r33值均保持在初始值的75%以上.这是由于环氧基团的开环使固化后的聚合物本身产生一定程度的交联,导致取向后的发色团被聚合物的交联网禁锢而不易弛豫,从而使这类PMMA型和PS型二阶非线性聚合物材料的热稳定性能得以提高.  相似文献   

4.
合成了双羟基双氨基偶氮苯化合物,将其分别与六亚甲基二异氰酸酯的缩二脲和2,4-甲苯二异氰酸酯进行交联反应合成了两种交联型二阶非线性光学聚合物,利用FTIR光谱和DSC对交反应过程和交联聚合物的玻璃化转变温度进行研究。采用UV-Vis吸收光谱对极化交联反应前后膜的取向及取向稳定性进行了研究。  相似文献   

5.
对一种新型含侧链二阶非线性光学基团的聚(氨酯-酰亚胺)材料的极化工艺进行了研究,通过对不同极化温度、极化电流、极化时间下的SHG相对强度的测定得到最佳极化工艺。利用序参数考察了极化膜在80℃和150℃下的取向稳定性,序参数在80℃经300h保持不变。  相似文献   

6.
含偶氮侧基的非线性光学聚酰亚胺的合成及取向稳定性   总被引:3,自引:2,他引:1  
通过硝基苯重氮氟硼酸盐与大分子聚酰胺酸在有机溶液中偶合,合成了2种新的含偶氮侧基的非线性光学聚酰亚胺,用紫外可见吸收光谱法测定了取向稳定性,用一维刚性取向气体模型估算了聚酰亚胺极化膜的非线性光学系数X^(2),这些聚酰亚胺具有高的玻璃化转变温度和好的热取向稳定性。  相似文献   

7.
异氰酸酯交联的环氧树脂基二阶非线性光学聚合物   总被引:1,自引:0,他引:1  
通过双酚A 二 (缩水甘油醚 )与苯胺的逐步聚合反应合成环氧树脂类先驱聚合物BPAN ,进一步通过先驱聚合物的后重氮偶合反应 ,制备了侧链带偶氮生色团的二阶非线性光学聚合物BPAN 1A NT .将BPAN 1A NT与适当量的异氰酸酯交联剂M2 0S混合 ,得到了双组分非线性光学聚合物体系BPAN 1A NT M2 0S .该体系在电场极化的同时可发生交联固化 ,极化后其二阶非线性光学系数高达 10 5 2pm v(λ =1 0 6 4 μm) ,同时还具有很好的极化偶极取向稳定性 ,2 0 0℃时的非线性光学系数仍可维持在初始的 80 %以上 .上述双组分非线性光学聚合物材料 (BPAN 1A NT M2 0S)同时具有高二阶非线性光学系数和高极化偶极取向稳定温度 ,可以预期 ,在聚合物电光调制器、光开关等器件中将有很好的应用前景 .  相似文献   

8.
氧化偶氮液晶二阶非线性光学聚合物的研究   总被引:1,自引:0,他引:1  
将4-[对硝基苯基氧化偶氮苯基]甘油单醚与六亚四基二异氰酸酯的缩二脲进行电场极化交联反应,合成交联型非线性光学聚合物,并用FT-IR光谱和DSC对交联反应过程进行了详细研究。利用紫外可见吸收光谱对膜极化前后的取向以及在室温和温下取向膜的稳定性进行了研究,并对极化膜的非线性光学系数d33了推算。  相似文献   

9.
通过自由基共聚合合成了含有高二阶非线性光学活性偶氮单元的侧链液晶共聚物。共聚物的液晶转变温度为DSC测定,实验证明当偶氮单元含量超过40mol%时,共聚物的液晶性消失。通过高压电场对该聚合物膜进行针尖电晕极化取向,并由紫外测试给出了聚合物膜的取向参数及其稳定性,对液晶聚合物的非线性光学性质进行了初步的研究。  相似文献   

10.
合成了一种新的带有光交联基团的电光聚合物,其高分子基体是双酚A环氧树脂,二阶非线性生色团对硝基苯胺和光交联基团肉桂酰氯都键接在高分子链上.将聚合物溶解后旋涂成膜,对薄膜进行电晕极化.极化的后阶段用紫外光照射,使聚合物体系交联成网络结构,形成生色团取向长时间稳定的聚合物电光薄膜.用这种聚合物电光薄膜构成外部电光调制系统,测量了共面波导上的电信号.  相似文献   

11.
《Journal of Coordination Chemistry》2012,65(16-18):3021-3033
Abstract

Three uranyl-containing coordination polymers, Cd(UO2)2(cpt)4(bdc)(H2O)2 (1), Zn(UO2)2(cpt)4(bdc)(H2O)2 (2) and UO2(OH)(cpt) (3) (Hcpt =4-(4’-carboxyphenyl)-1,2,4triazole, H2bdc =1,4-benzenedicarboxylic acid), have been synthesized under hydrothermal conditions by employing a bifunctional ligand (Hcpt) with both O-donors and N-donors. Compound 1 represents a 3-D framework with the point symbol of (62·84)(62·8)2 by the intersection of two sets of 1-D [Cd2(UO2)2(cpt)4(bdc)]n loop chains extended along different directions. Compound 2 exhibits a 2-nodal (3,4)-connected 2-D network with the point symbol (4·62)2(42·62·82). Compound 3 shows a 2-D network by the assembly of uranyl dimers and the cpt- anions. Although 1 and 2 have similar chemical formulas and the same coordination modes of ligands and metal centers, they possess totally different molecular frameworks, derived from the different radii of the secondary metal centers, Cd(II) and Zn(II). In addition, the optimal synthesis condition, thermal stability, luminescent properties, and IR spectra of 1 and 2 were also investigated.  相似文献   

12.
液晶基元直接竖挂于主链上的液晶共聚物的研究   总被引:2,自引:0,他引:2  
合成了含液晶基元的单体,4+4'-(对甲氧基-苯甲酰氧基)-苯甲酸氧基]-苯基-甲基丙烯酸酯,以及由此单体与苯乙烯,通过自由基共聚合反应合成了一系列含液晶性和非液晶性两种序列结构的共聚物.采用DSC、偏光显微镜和X-衍射方法研究了共聚物的液晶行为,发现单体和所有的共聚物(除CP—9外)均有很好的热致液晶性及较宽的液晶态温度范围;随苯乙烯单体单元摩尔百分含量的增加,共聚物的分子量、相转变温度和热失重温度基本上呈下降趋势.通讯联系人0.sg/dl的溶液,于40oC用乌氏粘度计测定.l·2单体合成合成路线如下:化合物I、11、Ill和IV的制备按文献l’]的方法进行.化合物1、11、Ill和IV经元素分析、‘H—NMR和MS等表征,结果与其化学结构~致.1.3聚合物的合成聚合反应和共聚物结构式表示如下:按单体(IV)与苯乙烯不同摩尔比,以DMF为溶剂,AIBN为引发剂(相当于单体摩尔数的0.50).通过封管聚合,在60oC水浴中反应36h,升温至70oC反应12h,抽滤,用DMF和甲醇洗,真空干燥.2结果与讨论2.l含液晶基元的单体(I)化合物1、11、Ill和IV经测试分析结果与其化学结构一致.由表1可见,单体?  相似文献   

13.
A new 3-D coordination polymer [Zn(L)2] (1) (HL?=?4-(pyridin-4-ylmethoxy)benzolic acid) was synthesized under hydrothermal conditions with Zn(OAc)2?·?2H2O and HL and characterized by single crystal X-ray diffraction (XRD). Compound 1 displays a 3-D 8-fold interpenetrating structure with diamondoid framework containing large adamantanoid cages. Meanwhile, it exhibits intense fluorescence at 402?nm in the solid state. In addition, powder XRD and thermogravimetric (TG) analysis for 1 are also reported.  相似文献   

14.
Four coordination polymers based on 4′-(2H-tetrazol-5-yl)biphenyl-4-carboxylic acid (H2TBPC), [Zn(μ3-TBPC)(H2O)]n (1), [Zn(μ3-TBPC)(Me2NH)]n (2), [Cd(μ3-TBPC)(bpy)]n (bpy = 4,4′-bipyridine, 3), and [Cd(μ4-TBPC)(H2O)]n (4), were constructed under hydrothermal conditions. The compounds are composed of M2(TBPC)2 binuclear ring as a building block. In 13, the binuclear rings are interconnected to three different 2-D networks with the same (4·82) topology. In 4, the binuclear rings are arranged into a 3-D framework with PtS-type topology. The results revealed that the structural diversity is mainly attributed to the coordination geometries of metal ion, the coordination modes of TBPC2?, and the auxiliary ligand. The thermal stabilities and luminescent properties of 14 have also been studied.  相似文献   

15.
孔治国  张艳娜  刘福义 《结构化学》2013,32(8):1175-1179
A new 1D coordination polymer, [Cd2(L1)2(L2)2]·H2O (1, H2L1 = 4-(carboxy-methoxy)benzoic acid and L2 = 2-(4-fluorophenyl)-1H-imidazo[4,5-f][1,10]phenanthroline), has been hydrothermally synthesized and characterized by elemental analysis and single-crystal X-ray diffraction. It crystallizes in triclinic, space group Pī with a = 9.985(5), b = 10.768(5), c = 12.512(5), α = 68.959(5), β = 80.354(5), γ = 79.663(5)°, V = 1227.4(10) 3, Z = 1, C56H36Cd2F2N8O11, Mr = 1259.73, Dc = 1.704 g/cm3, F(000) = 630, μ(MoKa) = 0.949 mm-1, R = 0.0261 and wR = 0.0655. The L1 anions link the neighboring Cd(II) atoms to form a 1D double chain structure. The L2 ligands are alternately located on both sides of the double chains. More interestingly, the lateral L2 ligands from adjacent double chains are paired to furnish strong π-π interactions, yielding a 2D supramolecular layer. N-H···O, O-H···N and O-H···O hydrogen bonds further stabilize the structure of 1. The luminescent property of 1 was studied in solid state at room temperature.  相似文献   

16.
在绝对乙醇介质中制备出 2个系列四硫富瓦烯四硫醇 ttftt4- ( tetrathiafulvalene tetrathiolate) Zn盐的配位高分子化合物 ,其组成分别为 [( Zn-ttftt) Mx]n( M=Mn,Co,Ni,Cu,Hg;x=0 .3,0 .4 ,0 .5 ,1 .3,0 .7)及[( Zn-ttftt) Lny]n( Ln=La,Er,y=0 .5 ;Ln=Nd,Eu,y=0 .6) .化合物在室温下均为在空气中稳定的黑色无定形粉末状固体 .用红外光谱及 X射线光电子能谱对化合物进行了表征 ,并进行了元素分析、热分析和电导率测定 . 2 5℃时 ,化合物均为典型半导体 .化合物 [( Zn-ttftt) Ni0 .5· 1 .9Et OH]n 的室温电导率高达 3.6S/cm  相似文献   

17.
Dummy molecularly imprinted polymers (DMIPs) for 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) were produced using three structural analogues as dummy template molecules. The chosen analogues were 4-(acetymethylamino)-1-(3-pyridyl)-butanol, 4-(methylamino)-1-(3-pyridyl)-1-butanol, and 1-(3-pyridyl)-1,4,-butanediol. The molecular recognition characteristics of the produced polymers were evaluated by X-ray photoelec-tron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FT-IR). Interactionsbetween NNAL and methacrylic acid should be cooperative hydrogen bonds while the ni-trogen atom of the pyridine ring and the oxygen atom of the nitroso group in NNAL are two of the hydrogen-bond acceptors. It was further demonstrated that DMIP synthesized by4-(acetymethylamino)-1-(3-pyridyl)-butanol had the best binding performance by XPS and FT-IR. Then dummy molecularly imprinted solid phase extraction (DMISPE) was developed for the determination of the analyte using the hit polymer as the sorbing material. Underoptimal conditions, the recovery of NNAL dissolved in standard solution reached 93%. And the investigated polymer exhibited much higher binding of NNAL when nicotine was acted as the competitive molecule. Also the proposed method was applied to the measurement of NNAL spiked in blank urine samples with recoveries ranging from 87.2% to 101.2%.  相似文献   

18.
Poly[4-(4-hydroxyphenoxy) benzoic acid] was prepared by the bulk polycondensation of 4-(4-acetoxyphenoxy) benzoic acid. Polycondensation was conducted at 350°C for 3 h under a reduced pressure of 0.1 mmHg and gave a polymer with X?n of 255. The polymer was characterized by elemental analysis, IR spectroscopy, differential scanning calorimetry, and wide-angle X-ray measurement. The crystal/nematic and nematic/isotropic phase transition temperatures of polymer, which depend on the molecular weight, were observed at about 300°C and 410°C, respectively. The polymers with low molecular weights showed nematic textures above 300°C. This nematic/isotropic phase transition temperature is lower than that of poly (4-hydroxybenzoic acid). This thermal behavior of polymer comes from ether units, which increase the flexibility (the rotation or torsion of skeletal bonds) of the polymer chain. © 1994 John Wiley & Sons, Inc.  相似文献   

19.
Reaction of FeCIz'6H20, pyridine-2,4,6-tricarboxylic acid(H3pyta) and NaOH in the hydrothermal system at 185 ℃ resulted in the formation of 1D coordination polymer[Fe(Hpyta)(H2O)2](1) based on Fe-Hpyta chains. When the abpt[abpt=-4-amino-3,5-bis(4-pyridyl)-l,2,4-triazole] ligand was employed in the reaction system, a 3D supramolecular porous network (H2bpt)[Fe(pyta)(H2O)2]·4H2O(2) was obtained. The framework was constructed with negative (Fe-pyta) chains and the positive H3bpt^+ in situ, formed from the abpt reagent, to form 1D channels filled with guest water molecules via hydrogen-bonds. X-Ray diffraction crystal structure analysis shows that complex 1 crystallized in the monoclinic system, space group C2/c, a=1.1490(5) nm, b=0.9008(4) nm, c=1.0058(5) nm, B=107.254(9)°, V=0.9942(8) nm3, Z=4; and complex 2 crystallizes in the triclinic system, space group P1 with a=0.90392(11) nm, b=0.96027(11 ) nm, c=1.55540(18) nm, a=73.558(2)°,B= 86.126(2)°,r= 68.745(2)°, V=1.2059(2) nm^3 and Z=2.  相似文献   

20.
Two novel non-centrosymmetric coordination polymer, [Zn2(PIDC)(H2O)Cl]n (1) and {[Mn(HPIDC)H2O]·2H2O}n (2) have been synthesized through hydrothermal method and characterized by IR, elemental analysis and single-crystal X-ray diffraction. Complex 1 crystallized in a chiral space group P212121 has a 2D network structure. Complex 2 is a 3D open framework with 1D channel where 1D zigzag water chains are reside through hydrogen-bonding interactions and crystallized in a chiral space group Cc. Both 1 and 2 display a strong second harmonic generation (SHG) response.  相似文献   

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