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1.
共轭聚席夫碱的掺杂及其导电性李春生顾尧刘长欣(山东建材学院应化系济南250022)关键词共轭聚合物聚席夫碱掺杂导电性中图分类号O631.23自1977年发现聚乙炔掺杂后具有导电性[1],人们对导电聚合物的研究投入了很大的热情。以后又相继发现了聚对苯撑...  相似文献   

2.
吴庆生  程丽娅 《分析化学》1995,23(11):1337-1340
本采用压缩X因子导数光谱技术实现了宽峰体系灵敏度的大幅度提高,提出了测定痕量锗的方法。在0.72mol/LH2SO4和3.0mol/LH3PO4的混酸介质中,锗-水杨基荧光酮-OP三元显色体系的压缩X因子四阶导数光谱摩尔响应系数达1.89×10^6L.mol^-1.cm^-1,灵敏度比常规光度法高12.4倍;最低检测出限为0.00033mg/L,比常规光谱法低4倍;选择性也进一步提高,绝大多数离  相似文献   

3.
5′—硝基水杨基荧光酮分光光度测定微量碲   总被引:4,自引:0,他引:4  
在pH4.1~4.6乙酸盐缓冲介质中,碲(Ⅳ)与5′硝基水杨基荧光酮(5′-NSF)溴化十六烷基吡啶(CPB)反应形成组成比为1:4;4的水溶性和稳定性皆佳的红色三元配合物,最大吸收波长为542nm,表观摩尔吸光系数为1.02×10^5L.mol^-1.cm^-1,桑德尔灵敏度是1.25×10^-3μg.cm^-2线性范围0~0.40mg/L,据此提出了测定碲的灵敏,简便的分光光度分析新方法,直接  相似文献   

4.
合成和表征了3,3-二乙酸乙酯基-2,4-戊二酮。得出其为单斜晶系,空间群为C2/c,a=14.864(2),b=10.5674(7),c=9.5053(6),β=101.825(6)°,υ=1461.13(2)3,Z=4,Dx=1.238mg/m3,μ=0.098mm-1,finalR=0.0314,Rw2=0.0891  相似文献   

5.
庆大霉素与3,5—二溴水杨醛的缩合反应及其应用   总被引:1,自引:0,他引:1  
本文研究了庆大霉素与3,5-二溴水杨醛缩合成席夫碱的条件及其应用,在加热条件下,庆大霉素与3,5-二溴水杨醛缩合成亮黄色席夫碱,其分子反应比为,庆大霉素+3,5-二溴水杨醛=1+1,据此提出了庆大霉素生物效价总量的光度测定法,庆大霉素在0~118.9μg/mL内符合比尔定律,λmax=430nm表观摩尔吸光系数ε=9.98×10^4L.mol^-1.cm^-1本法干扰少,重现性好。  相似文献   

6.
KBrO3—KBr紫外分光光度法测定痕量水杨酸   总被引:5,自引:0,他引:5  
研究了HCl溶液中KBrO3-KBr紫外分光光度法测定水杨酸的条件,建立了测定痕量水杨酸的新方法。结果表明,在0.6mol/LHCl,3*10^-5mol/LKBrO3,5*10^-4mol/LKBr,6*10^-4mol/lKI溶中测定水杨酸,其线性范围为0.2-4.0mg/L,表观摩尔吸光系数为1.9*10^-4L.mol^-1.cm^-1,Sandell为7.3μg/cm^2。sg if e  相似文献   

7.
本文研究了溴化十二烷基二甲基苄基铵-溴百里酚蓝与阴离子表面活性剂显色反应的适宜条件。结果表明,在pH7.4~8.2范围内阴离子表面活性剂与题示试剂形成1:2:1的绿色离子缔合物,其最大吸收峰位于614nm处。表现摩尔吸光系数分别为:=3.99×10 ̄4L·mol ̄(-1)·cm ̄(-1);=3.70×10 ̄4L·mol ̄(-1)·cm ̄(-1);=1.71×10 ̄4L·mol ̄(-1)·cm ̄(-1)。SDBS在0~195μg/10mL,SDS在0~158μg/10mL,SLS在0~60μg/10mL范围内遵守比耳定律。该法用于河水和生活废水中阴离子表面活性剂测定,结果满意。  相似文献   

8.
聚(N—十二烷基—3—苯基吡咯)的研究   总被引:2,自引:1,他引:2  
合成了一种吡咯的双取代衍生物:N-十二烷基-3-苯基吡咯,并用化学氧化法对其实施了聚合反应。该反应生成的导电聚合物可溶于一般有机溶剂,用溶剂蒸发制膜的方法可制得柔软的自支撑薄膜,用四电极方法测得掺杂态薄膜的电导率约为0.05S/cm。并通过元素分析、GPC、FT-IR、1H-NMR等手段对其分子结构进行了表征。  相似文献   

9.
研究了碳酸丙烯酯(添加量5%)与γ-丁内酯(添加量10%)对由数均分子量为800的聚氧化乙烯(PEO800)大单体交联不饱和聚酯(含LiClO4)形成的接枝聚酯网络的离子导电性能影响,发现其电导率主要取决于体系中的LiClO4浓度.当[EO链节]/[Li+]=30时,室温电导率达最大值,σ298K=(4.0—4.5)×10-5Scm-1.这类接枝聚酯网络的玻璃化转变温度(Tg)同样取决于盐类浓度,而与网络的交联程度无关.网络中的极性添加剂并不显著影响其交联程度与Tg,但较大幅度提高离子导电性能,这可能与极性添加剂加速载荷离子在导电通道中的迁移性有关.若在上述接枝网络中引入环氧树脂网络,形成接枝聚合物互穿网络,则成膜后的机械强度有进一步提高,同时具有优良的室温电导率,σ298K=2.4×10-5Scm-1。  相似文献   

10.
在pH4.1~4.6乙酸盐缓冲介质中,碲(Ⅳ)与5′-硝基水杨基荧光酮(5′-NSF)、溴化十六烷基吡啶(CPB)反应形成组成比为1∶4∶4的水溶性和稳定性皆佳的红色三元配合物,最大吸收波长为542nm,表观摩尔吸光系数为1.02×105L·mol-1·cm-1,桑德尔灵敏度是1.25×10-3μg·cm-2,线性范围为0~0.40mg/L。据此提出了测定碲的灵敏、简便的分光光度分析新方法,直接用于测定硒粉中微量碲,结果较满意。  相似文献   

11.
马来酸酐-醋酸乙烯酯交替共聚物以聚乙二醇单醚醇解,得到带有不同长度的聚醚氧侧链的羧酸型梳状聚合物,其碱金属盐在加入适当增塑剂成膜后,可作为聚合物单阳离子导体,其结构以非晶态为主,具有较低的玻璃化转变温度及较好的热稳定性,增塑后的室温电导率最高可达10-5S/cm.研究发现,适当增加侧链的长度有利于提高聚合物膜的离子电导率.此外,还详细探讨了增塑剂、阳离子半径、温度及外加频率等因素对电导率的影响.  相似文献   

12.
 A novel alcohol-soluble polyorganosiloxane containing amino side groups, poly[3-(4-aminophenoxy)propylmethylsiloxane] (2), was first prepared by the reduction of nitro groups on 4-nitrophenoxypropyl side chains of poly[3-(4-nitrophenoxy)propylmethylsiloxane] (1). The reaction proceeded easily with nearly 100% conversion. The synthesized alcohol-soluble polymer 2, which has potential application as a precursor for preparing advanced functional polymers, was characterized by FTIR 1H-NMR, 13C-NMR, 29Si-NMR, VPO and GPC, respectively.  相似文献   

13.
Novel poly-Schiff bases (PSB's) that contain trans-1,2-bis(9-carbazolyl)cyclobutane(DCZB) units were synthesized by the direct polycondensation of trans-1,2-bis(3-formyl-9-carbazolyl)cyclobutane with aromatic diamines in n-amyl alcohol at 160°C. Complexation of these PSB's and of poly(vinyl DCZB) (PVDCZB) with iodine produced cation-radical salts which resulted form the transfer of an electron from DCZB moieties to iodine. All the undoped polymers were insulators having electrical conductivity of the order of 10?10–10?12 S cm?1 depending on the structure of polymers. By doping with iodine, the electrical conductivity increased by several orders of magnitude and reached a value of 10?3 S cm?1 in the case of PVDCZB and 10?5–10?6 S cm?1 in the case of PSB's. The electrical conductivity of doped PSB's increased with decreasing diamine length. PVDCZB having the same iodine content per carbazole unit as poly(9-vinyl-carbazole) (PVK) has a greater electrical conductivity than PVK.  相似文献   

14.
Three fully amorphous comb-branch polymers based on poly(styrene-co-maleic anhydride) as a backbone and poly(ethylene glycol) methyl ether of different molecular weights as side chains were synthesized. SiO2 nanoparticles of various contents and the salt LiCF3SO3 were added to these comb-branch polymers to obtain nanocomposite polymer electrolytes. The thermal and transport properties of the samples have been characterized. The maximum conductivity of 2.8×10–4 S cm–1 is obtained at 28 °C. In the system the longer side chain of the comb-branch polymer electrolyte increases in ionic conductivity after the addition of nanoparticles. To account for the role of the ceramic fillers in the nanocomposite polymer electrolyte, a model based on a fully amorphous comb-branch polymer matrix in enhancing transport properties of Li+ ions is proposed.  相似文献   

15.
The dependences of the electrical conductivity, ESR spectral linewidths, spin concentrations, and g-factor on the level of iodine doping of poly(4-aminoazobenzene), synthesized by the oxidative polymerization of 4-aminoazobenzene with iodine, were studied for the first time. The polymers were studied by ESR and UV spectroscopy. With an increase in the level of iodine doping, the electrical conductivity of the polymers increases from 3·10−10 to 4·10−1 S m−1, the ESR linewidth increases from 0.96 to 1.94 mT, and the g-factor increases from 2.004 to 2.007. The spin concentration changes ambiguously, depending on the doping level. In the iodine-doped polymers, spins are mainly localized on two nitrogen atoms of the azo groups.  相似文献   

16.
Initiation of anionic polymerization of 4-vinyl-pyridine (4-VP) in tetrahydrofuran solution, using organo-metallic compounds of Na and K, involves the same type of side reactions as the polymerization of 2-vinyl pyridine (2-VP). The living polymers of 2- and 4-VP have similar u.v. spectra. The values of the dissociation constants of ionic species of 2- and 4-VP are similar when the chain [poly(styrene-b vinyl-4 pyridine)] contains one 4-VP unit (Kn ≈ 10?9). But when the size of 4-VP block increases, the conductivity goes up to the value observed for living polystyrene (KD ≈ 10?7). This phenomenon could be due to a solvation of the counter-ion by the poly 4-vinyl pyridine chain, acting as a polydentate complexing agent.  相似文献   

17.
设计合成了两种主链结构相同、但取代方式不同的带有(-)-trans-桃金娘烷氧基手性侧基的规整连接聚(对亚苯基亚乙炔基-altr-间亚苯基亚乙炔基)(Myr-PMPE-1和Myr-PMPE-2),其中Myr-PMPE-1分子中手性取代基在分子链上均匀分布,而Myr-PMPE-2分子中手性取代基的分布则交替地存在局部"拥挤"和局部"松散".利用紫外-可见吸收光谱、荧光光谱和圆二色谱对两种聚合物膜的手性光性能进行了研究.结果表明,退火处理对Myr-PMPE-1膜的UV吸收和荧光光谱以及光学活性的影响都不明显,其最大不对称因子|gmax|为1.62×10-4;而退火处理对Myr-PMPE-2膜影响显著,未经退火处理或退火温度≤100℃时,Myr-PMPE-2膜几乎不显示光学活性,但当退火温度高于120℃时,随着退火温度的升高和退火时间的延长,Myr-PMPE-2膜的UV吸收和荧光光谱均稍有红移,特别是膜的光学活性显著提高,经140℃退火处理4 h后,其|gmax|可达3.07×10-3,比Myr-PMPE-1膜的高出1个数量级.  相似文献   

18.
比较了3种主链结构相同而侧链结构不同的磺化聚芳醚(SPAE)材料的性能. 分析了侧链结构对聚合物的吸水、 溶胀及质子传导行为的影响. 结果表明, 在相同的离子交换容量(IEC)条件下, 具有柔顺脂肪族侧链的聚芳醚材料具有较高的质子传导率. 其原因是由于柔顺的脂肪族侧链比刚性的芳香族侧链更易运动, 有利于侧链末端磺酸基团的聚集, 进而形成离子簇. 3种聚合物微观形貌的分析结果表明, 含柔顺侧链结构的聚合物薄膜具有更大的质子传输通道, 其结果与聚合物的宏观吸水和传导现象相吻合.  相似文献   

19.
2-Alkylanilines with alkyl groups in the range of 4–15 carbon atoms were synthesized via a known method as well as via a more general path which should allow the introduction of a larger variety of substituted alkyl groups into the ortho position of aniline, e.g., alkenyl or OH, NH2, COOH, and phenyl functionality. Polymerization was found to be achievable according to a method previously described for unsubstituted aniline, i.e., chemically with Cu(ClO4)2 · 6H2O in acetonitrile. Intrinsic viscosities of the obtained poly(2-alkylaniline)s lay between 0.10 and 0.26 dL/g (97% H2SO4 at 30°C). The dc conductivity of the HCl salts decreased with increasing length of the alkyl side chains from 1 S/cm (polyaniline) over 3 X 10?4 S/cm [poly(2-butylaniline)] to 1 X 10?6 S/cm poly(tridecylaniline). Further characterization of the polymers were performed by means of UV/VIS/NIR-and-IR spectroscopy, in dilute solutions or as KBr pellets, respectively, and by solubility tests. © 1993 John Wiley & Sons, Inc.  相似文献   

20.
The free-radical initiated copolymerization of 2-(4-chloro-1-naphtyloxy)-2-oxoethyl methacrylate (ClNOEMA) with 2-(diethylamino) ethyl methacrylate (DEAEMA) was carried out in 1,4-dioxane solution at 70 ± 1°C using 2,2′-azobisisobutyronitrile (AIBN) as an initiator with different monomer-to-monomer ratios (ranging from 0.15 to 0.85) in the feed. The copolymer composition obtained by elemental analysis led to the determination of reactivity ratios employing Fineman-Ross (F-R) and Kelen-Tüdös (KT) linearization methods. These parameters were also estimated using a non-linear computational fitting procedure, known as reactivity ratios error in variable model (RREVM). The prepared homo and copolymers were tested for their antimicrobial activity against bacteria and yeast. These copolymers have been converted into novel salts by reaction with the iodemethane (CH3I). The copolymers and the corresponding salts have been characterized fully by a range of spectroscopic analysis techniques. The electrical conductivity dependence of temperature of the polymers were measured and the polymers exhibit the semi-conducting behavior, confirming that the electrical conductivity increases with increasing temperature. The poly(CINOEMA-co-DEAEMA) polymer doped by CH3I for 15 min shows the highest conductivity. The optical band gap, activation energy and room temperature conductivity values of these polymers were obtained. These electronic parameters suggest that the poly(CINOEMA-co-DEAEMA)s doped by CH3I for 15 min is an organic semiconductor with the thermally activated conduction mechanism.  相似文献   

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