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1.
为了制备电致偏振光发光材料, 以对苯二乙炔和2,5-二溴苯衍生物为单体,通过Sonogashira偶联反应, 采用不同Pd催化剂, 合成了一种侧基横挂偶极基团的液晶聚苯撑乙炔. 单体的化学结构通过IR, NMR和元素分析等方法得到确证. 聚合物外观为黄色粉状固体, 室温下溶于CHCl3和THF等有机溶剂. 将聚合物加热到各自的玻璃化转变温度以上都能形成液晶态并显示双向液晶性. 考察了不同催化剂对合成的聚合物的分子量、聚合物链中单体单元的结构排列以及液晶性质的影响. 结果表明, 两种不同的Pd催化剂对合成的聚合物的分子量以及液晶态温度范围影响不大, 但对聚合物的立构规整性以及聚合物的液晶态织构有较大的影响. Pd(PPh3)4作催化剂合成的聚合物中单体单元的结构排列较单一, 可以观察到清晰的液晶态织构. 以PdCl2(PPh3)2为催化剂合成的聚合物链中单体单元的结构排列相对复杂, 液晶态织构不明显. 变温X 射线衍射研究证实聚合物均为向列相液晶.  相似文献   

2.
通过单体4-[(2,5-二溴苯)乙炔基]苯胺和1,4-二乙炔基-2,5-二戊氧基苯之间的Sonogashira偶合反应合成了带有p-氨基苯乙炔基共轭侧基的聚对苯撑乙炔((PAnPE)). 该共轭聚合物的THF溶液((2××10--5 mol•·L--1))在473和519 nm处呈现两个比较强的荧光发射峰. 通过调节在聚合物PAnPE-THF溶液中所加入三种沉淀剂((甲醇、乙酸、稀盐酸溶液))的体积比例, 来改变PAnPE分子链的聚集态结构, 进而研究对其发光性能的影响规律. 实验结果表明: 由于沉淀剂与聚合物PAnPE分子链之间相互作用能力与方式的不同, PAnPE两个荧光峰的发射强度因聚合物分子链聚集结构不同而呈现不同的变化规律, 这有助于实现在化学传感器中的应用.  相似文献   

3.
聚苯撑乙炔-苯并噻二唑共聚物的合成及光谱性能   总被引:2,自引:0,他引:2  
牛俊峰  赵军子  李惠  曾翎  蒋家新  路胜利 《化学学报》2005,63(13):1220-1224
利用钯催化剂[Pd(PPh3)2Cl2]和相转移催化剂(PTC), 采用Heck交叉偶联缩聚反应合成了聚(苯撑乙炔撑-苯并噻二唑)系列交替共聚物(PPE-BT), 比较了聚合物的紫外吸收光谱和荧光光谱特征.  相似文献   

4.
利用Sonogashira偶联反应,首次合成了溶解性好且为乙烯基封端的聚苯撑乙炔化合物(PPE),通过。HNMR谱、IR光谱对其结构进行了表征.将其热固化后,通过紫外可见吸收光谱和荧光发射光谱分析,证明了PPE的交联能够在一定程度上消除分子链间的相互作用和π-π堆积效应.  相似文献   

5.
主链含三苯胺单元的聚苯乙炔的合成及其电致发光性能   总被引:2,自引:1,他引:2  
采用4-甲基三苯胺的二醛基化合物分别与对、间、邻-二甲基苯的膦盐反应,制备了三种含三苯胺单元的聚苯乙炔类共聚物TPA-PPV、TPA-PmPV和TPA-PoPV。结果表明:TPA-PPV和TPA-PmPV具有良好的热稳定性和光电化学性能,该类共聚物不但具有良好的空穴传输性能,而且作为发光材料应用于发光器件时可以调制发光颜色。  相似文献   

6.
聚苯乙炔(PPA)是一种共轭高分子材料,具有较好的光电导性能。因反式PPA比顺式具有较高的光暗比,本文研究了反式PPA的光导和暗导特性,得到的光、暗导曲线基本平行,说明本征载流子和光生载流子的输运机制是相似的。在欧姆区的光导和暗导的活化能分别为0.24±0.03eV和0.58±0.03eV。  相似文献   

7.
修振佳  程悦生  洪群发 《色谱》1997,15(5):428-430
使用静态涂渍法,在毛细管柱内壁涂渍新型苯撑基色谱固定液,通过原位交联,提高了液膜不可抽提性及稳定性。苯基通常被连接在聚硅氧烷硅原子的侧链上,如果两个硅原子之间通过苯联结而不是通过氧原子联结,则可形成聚苯撑基硅氧烷[1],这种聚硅氧烷的弹性好。采用含50%聚苯撑基硅氧烷研制出交联毛细管柱,并对制备过程重复程度进行了考察,评价了柱子的综合性能,简单介绍了柱子的极性及适用范围。  相似文献   

8.
通过4-溴苯甲醇和三甲基硅基乙炔的Sonagashira偶联反应与三甲基硅基的脱除反应,合成4-乙炔基苯甲醇.以4-乙炔基苯甲醇为引发剂,以有机氮杂环化合物DBU为催化剂,常温常压下进行丙交酯的活性开环聚合反应,采用1H-NMR和GPC对产物结构、分子量与分子量分布进行表征分析,结果表明,合成以了苯乙炔为端基的聚乳酸大...  相似文献   

9.
10.
聚苯撑乙烯(PPV)类聚合物是优异的发光材料, 有望作为全色显示中三基色的材料之一得到应用. 我们采用2-溴-1,4-亚二甲苯二乙酯为原料, 合成了商品名为Supper Yellow PPV (SY PPV)的苯基取代PPV. 中间体、单体和聚合物的结构都通过核磁共振、元素分析进行了表征. SY PPV的吸收峰在434 nm, 吸收边在510 nm, 带隙2.44 eV. 光致发光峰值和电致发光峰值分别在516和552 nm. SY PPV的器件性能为: 启动电压为2.4 V, 最大亮度大于49000 cd·m-2, 最大流明效率为21 cd·A-1, 显著优于采用老方法合成SY PPV的最大流明效率(16-18 cd·A-1).  相似文献   

11.
Two new poly(phenylene ethynylene)s with alkoxyphenyl substituents were synthesized and characterized. The polymers were amorphous, dissolved readily in common organic solvents, and showed glass‐transition temperatures at 162–175 °C. They showed blue photoluminescence both in solution and in the solid state due to the steric interaction between the substituents and the main chain that caused an interruption of the conjugation length. The quantum yields in a tetrahydrofuran solution were up to 0.63. Excimer emission was the dominant product of the photoexcitation of thin films of the polymers. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 1449–1455, 2002  相似文献   

12.
Memory effects of several copolymers of poly(ethylene oxide) (PEO) and poly(ethylene terephthalate) (PET) were illustrated with photos, determined with shrinkage experiments and characterized by the recovery of samples to their original figures. Copolymers of appropriate composition could undertake an approximately full recovery which is tightly related to the annealing temperature at which shrinkage of samples occurs to some extent. Melting and recrystallization of PEO segments may be responsible for the memory effect. The memory properties of samples almost kept unchanged after many fatigue cycles (e.g. 15–20 cycles), which could make these copolymers useful in practical applications as novel shape memory materials. © 1997 John Wiley & Sons, Ltd.  相似文献   

13.
A series of multiblock poly(ether urethane)s comprising poly(ethylene glycol) (PEG), and poly(propylene glycol) (PPG) segments were synthesized. Their aqueous solutions exhibited thermogelling behavior at critical gelation concentrations (CGC) ranging from 8 to 12 wt%. The composition and structural information of the copolymers were studied by GPC and 1H NMR. The critical micellization concentration (CMC) and thermodynamic parameters for micelle formation were determined at different temperatures. The temperature response of the copolymer solutions were studied and found to be associated with the composition of the copolymers.  相似文献   

14.
In the rapidly evolving multidisciplinary field of polymer therapeutics, tailored polymer structures represent the key constituent to explore and harvest the potential of bioactive macromolecular hybrid structures. In light of the recent developments for anticancer drug conjugates, multifunctional polymers are becoming ever more relevant as drug carriers. However, the potentially best suited polymer, poly(ethylene glycol) (PEG), is unfavorable owing to its limited functionality. Therefore, multifunctional linear copolymers (mf‐PEGs) based on ethylene oxide (EO) and appropriate epoxide comonomers are attracting increased attention. Precisely engineered via living anionic polymerization and defined with state‐of‐the‐art characterization techniques—for example real‐time 1H NMR spectroscopy monitoring of the EO polymerization kinetics—this emerging class of polymers embodies a powerful platform for bio‐ and drug conjugation.  相似文献   

15.
袁攀  胡苏军  应磊  杨伟 《应用化学》2010,27(3):262-266
用Suzuki缩聚反应合成了以三-(2-间溴苯基吡啶)合铱为核,以聚2,5-二辛氧基苯为枝的超支化电磷光绿光聚合物(PPPIrppy)。 聚合物中当铱配合物摩尔分数大于0.5%时,主体的发射被完全淬灭,电致发光(EL)光谱只有位于520 nm处的绿光发射,表明主客体之间发生了有效的能量转移。 基于铱配合物摩尔分数为1%的聚合物的发光器件(器件结构:ITO/PEDOT:PSS/emissive layer/Ba/Al)在电流密度为40×10-3 A/cm2时,最大电流效率达到2.89 cd/A,器件的最大亮度达到1 689 cd/m2,色坐标为(0.34,0.59)。  相似文献   

16.
17.
Poly(p-phenylene benzobisoxazole)/poly(pyridobisimidazole) block copolymers (PBO-b-PIPD) were prepared by introducing poly(pyridobisimidazole) (PIPD) moieties into the main chains of poly(p-phenylene benzobisoxazole) (PBO) in order to enhance its photostability. PBO and copolymer fibers were directly prepared from the polymerization solutions by dry-jet wet-spinning. Chemical structures and molecular chains arrangement of the block copolymers were characterized by Fourier transform infrared (FTIR) spectroscopy, solid-state 13C-NMR and wide angle X-ray diffraction (WAXD). Thermal stability of the copolymers was investigated by thermogravimetric analysis (TGA) in nitrogen. Thin films of PBO and copolymers were cast from methanesulfonic acid (MSA) solutions. Both the films and fibers were exposed to UV light to determine their photostability. Changes in the chemical structures and surface morphologies of the films were characterized by FTIR spectra and scanning electronic microscopy (SEM), respectively. After UV light exposure, the retention of strength for copolymer fibers is improved compared to PBO fibers. The results revealed that copolymers suffered less photodegradation in comparison with homopolymer. The mechanism for the improved photostability of the copolymers was discussed.  相似文献   

18.
液晶高分子聚苯撑苯并二噁唑的合成、结构与性能   总被引:7,自引:0,他引:7  
本文以间苯二酚为原料,合成了缩聚单体4,6-二胺基1,3-间苯二酚盐酸盐。在多聚磷酸介质中与对苯二甲酸经分段升温缩聚得聚苯撑苯并二噁唑(PBZO).用元素分析法,X-光衍射法、X-光平板照相、FTIR和C~(13)-NMR研究了PBZO的结构.测定了PBZO/MSA体系的特性粘数。测定了PBZO的力学性能和热稳定性。结果表明PBZO是继PBZT后又一种新型的高性能液晶高分子材料。  相似文献   

19.
苯并双噁唑类聚合物的合成   总被引:1,自引:0,他引:1  
详细介绍了以4,6-二氨基间苯二酚盐酸盐(DADHB)为原料,采用多聚磷酸法、三甲基硅烷基化法、中间相聚合法、单体成盐法合成聚对苯撑苯并双噁唑(PBO),还有以4,6-二硝基间苯二酚(DNR)为原料,先选择还原制得4-氨基-6-硝基间苯二酚盐酸盐,进而与对甲氧羰基苯甲酰氯进行缩环合获得苯并噁唑化合物,再催化加氢合成AB型PBO新单体2-(对甲氧羰基苯基)-5-氨基-6-羟基苯并噁唑,最后自缩聚反应制备PBO的新路线.另外,本文还介绍了直链烯烃型、直链脂肪烷烃型、稠环芳烃型、联苯取代基型、杂环型、聚醚型等苯并双噁唑类聚合物的合成方法.  相似文献   

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