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1.
利用静电吸附逐层自组装方法在有机溶剂N,N二甲基甲酰胺(DMF)和H2O的混合介质中制备非水溶性偶氮聚电解质自组装多层膜.研究了DMF和H2O的配比对自组装膜生长、结构与表面形态的影响.结果表明,DMFH2O的混合溶剂是非水溶性偶氮聚电解质自组装的理想介质,二者之间的配比对自组装膜的生长速度,膜的结构以及表面形态均有显著影响.随着混合溶液中DMF含量的升高,自组装膜的生长速度逐渐下降但线形生长关系越来越好,所得自组装膜中偶氮生色团的H聚集程度逐渐下降,而且自组装膜的表面越来越平整.  相似文献   

2.
利用浸泡和旋涂静电吸附自组装技术制备了含有偶氮生色团的聚电解质薄膜,比较了两种方法在自组装膜生长机理、膜结构以及膜光学性能方面的差异.利用紫外光谱和椭偏仪检测自组装膜的生长情况,利用原子力显微镜对膜表面结构进行了表征,并用偏振激光在膜表面进行了写光栅实验.结果表明,采用浸泡法和旋涂法都可以制备出表面光滑均匀的含偶氮生色团的聚电解质自组装膜.但是浸泡法自组装膜的生长速度要比旋涂法快.在自组装膜厚度较小的情况下,旋涂法得到的自组装膜可以写出明显的光栅而浸泡法不可以.随着自组装膜厚度的增加,两种方法得到的自组装膜都可以写出明显的光栅.这些结果说明浸泡法自组装膜内部聚电解质分子的层间穿插比较严重,而旋涂法自组装膜内分子穿插要弱得多.  相似文献   

3.
超支化聚负离子/超支化聚正离子自组装膜的制备及反应   总被引:5,自引:2,他引:3  
自1991年以来,静电吸附自组装已发展成为制备具有特定纳米微结构聚电介质多层超薄膜的有效技术。近年来,由于树枝状聚合物和超支化聚合物独特的物理化学性质,文献中已将它们与线性聚电解质一起用于静电吸附自组装过程,但完全基于超支化聚合物分子间的自组装过程还鲜见报道,超支化聚合物所具有的大量末端和内部(如叔胺基)官能团,不仅可以用于调节自组装行为及组装膜的表面形貌,  相似文献   

4.
两种侧链偶氮聚电解质自组装膜中生色团取向研究   总被引:1,自引:0,他引:1  
用偏振紫外光谱研究了两种侧链偶氮聚电解质静电逐层自组装膜中偶氮生色团的初始取向 .讨论了不同的组装条件对自组装膜中偶氮生色团取向的影响 .进一步探讨了偶氮聚电解质自组装膜的结构特点 .研究表明 ,侧链偶氮聚电解质自组装膜中的偶氮生色团存在一定程度的面内取向 ,自组装的各种影响条件和聚合物结构等 (pH值、侧链柔性间隔基团长度、以及偶氮生色团官能度等 )与自组装膜中偶氮生色团的面内取向程度存在一定的相关性 .通过研究偶氮生色团的取向和影响因素 ,可以深入认识侧链偶氮聚电解质的自组装行为  相似文献   

5.
智能响应与自修复的层层组装聚合物膜   总被引:2,自引:0,他引:2  
陈栋栋  马莹  孙俊奇 《高分子学报》2012,(10):1047-1054
具有刺激响应性和自修复功能的复合膜是重要的仿生功能膜材料.层层组装是一种基于物质交替沉积而制备复合膜的方法,可以实现膜的结构和组成的精确调控.通过结构与组成的精确调控,基于层层组装制备的微米厚度的聚电解质厚膜可以对外界刺激产生快速有效的响应,因而在制备智能仿生膜材料方面具有重要的价值.本文以作者的研究结果为基础,阐明了基于层层组装的聚电解质膜可以成功用于制备湿度和温度响应的双结构自支持膜和高效的促动器及行走机器,以及自修复超疏水和划痕修复聚电解质膜.  相似文献   

6.
采用静电自组装方法在五氧化二钽(Ta2O5)介质氧化膜上制备了聚二烯丙基二甲基氯化铵(PDDA)/聚苯乙烯磺酸钠(PSS)和聚二烯丙基二甲基氯化铵/聚-3,4-乙烯二氧噻吩-聚苯乙烯磺酸钠(PEDOT-PSS)超薄膜.研究了两种自组装超薄膜在Ta2O5介质氧化薄膜上的组装特性.结果表明两种自组装膜能够稳定地组装于Ta2O5介质膜表面,并有效降低薄膜的表面粗糙度.进一步研究了两种自组装超薄膜修饰的Ta2O5电容结构的电性能.结果表明静电自组装膜对Ta2O5介质膜表面进行修饰后,有效地隔离了介质氧化膜中的缺陷,降低了电容的漏电流并提高耐电压能力;研究还发现不同厚度的超薄膜对Ta2O5电容结构的耐压特性有不同程度的影响,较厚的薄膜可以更好地提高电容的耐压能力并降低漏电流,但会增加电容的等效串联电阻(ESR).另外,在相同薄膜层数的情况下,聚合物电解质PEDOT-PSS良好的导电性能降低了复合超薄膜的电阻,使得PDDA/PEDOT-PSS修饰的电容结构ESR值较低.  相似文献   

7.
偶氮聚电解质的静电逐层自组装是实现偶氮聚合物功能性的重要手段,是制备诸如光存储材料、光开关材料和非线性光学材料等的新途径.因此,光响应性偶氮聚电解质的静电逐层自组装已引起了人们的广泛关注.静电逐层自组装通常在水溶液中进行,即通过基材在在水溶液中的交替浸渍和逐层  相似文献   

8.
酞菁铜衍生物与聚电解质的自组装   总被引:4,自引:0,他引:4  
用原子力显微镜研究了阿利新蓝(Alcian Blue)和聚电解质自组装膜的表面形貌结构以探讨染料小分子的静电自组装途径。并通过将氯甲基酞菁小分子挂接在高分子链上,制备了一种高分子染料,然后和聚电解质组装成一种高分子复合物。  相似文献   

9.
有机分子与聚电解质静电吸附成膜特性研究   总被引:1,自引:0,他引:1  
选取多种有机分子及聚电解质,采用静电吸附自组装法制备了聚电解质,聚电解质、聚电解质,有机分子、有机分子,有机分子的复合薄膜,讨论了这些体系的静电吸附成膜特性及其成膜机理.  相似文献   

10.
静电组装金纳米粒子制备局域表面等离子体共振传感膜   总被引:4,自引:1,他引:3  
采用聚电解质自组装技术制备局域表面等离子体共振(LSPR)传感膜的方法, 在玻璃基片上依次沉积聚电解质PDDA, PSS和PVTC, 并通过静电吸附构建胶体金纳米粒子自组装膜形成LSPR传感膜. 利用扫描电镜对LSPR传感膜表面形貌以及膜中金纳米粒子的粒径进行了表征, 同时通过紫外-可见消光光谱对其灵敏度和渗透深度等重要参数进行检测. 研究结果表明, 所制备的LSPR传感膜粒子分布均匀、单分散性好、稳定性高、重现性好; 消光峰位对样品溶液折射率的检测灵敏度为71 nm/RIU, 相应的峰强检测灵敏度为0.21 AU/RIU, 对表面吸附层的渗透深度约为16 nm.  相似文献   

11.
N,N-Dimethylformamide (DMF)/H2O mixtures were used as solvents to fabricate azo polyelectrolyte (PEAPH)/poly(diallyldimethyl ammonium chloride)(PDAC) self-assembled multilayers with the layer-by-layer electrostatic adsorption technique. PEAPH is a copolymer of acrylic acid and azobenzene-containing acrylate. The effect of the ratio of DMF to water on the multilayer growth, structure and surface morphology was studied in some details. Results show that DMF/H2O mixtures are proper media for PEAPH/PDAC multilayer fabrication. The ratio of DMF to water in the mixture has significant influence on the multilayer structure and surface morphology. With the increase of DMF content, the multilayer thickness has a better linear growth relationship with the bilayer number, and the multilayer surface becomes smoother. Moreover, azo chromophores show less H-aggregation when the multilayers are fabricated from DMF/H2O mixtures with higher DMF contents. These studies demonstrate that using organic solvent and water mixtures is an effective way to control the multilayer construction by adjusting the media properties. This method can be applied to multilayer fabrication of other water-insoluble polyelectrolytes. __________ Translated from Acta Polymerica Sinica, 2005, (4) (in Chinese)  相似文献   

12.
不同pH条件下木质素磺酸钠的静电逐层自组装研究   总被引:1,自引:0,他引:1  
以来源于造纸废液中的木质素磺酸钠(SL)为研究对象,利用静电逐层自组装技术,与聚二烯丙基二甲基氯化铵(PDAC)交替吸附,制备木质素磺酸钠的自组装多层吸附膜.研究了不同pH值条件下木质素磺酸钠在固体表面的静电吸附规律.木质素磺酸钠的自组装过程用紫外-可见光吸收光谱来监控,而自组装膜的表面形貌用原子力显微镜来观察.研究表明,SL与PDAC多层吸附膜的紫外-可见光吸收光谱强度随层数增加而线性增长,说明SL/PDAC多层吸附膜的厚度增长是以逐层自组装的方式进行的.木质素磺酸钠浸渍溶液的pH值对多层吸附膜的厚度和表面形貌产生重要的影响.在所研究的pH范围内,pH值越低,越有利于生成吸光度高的自组装膜,而得到的自组装膜的表面粗糙度越大。  相似文献   

13.
A bolaform Schiff base, N,N'-bis(salicylidene)-1,10-decanediamine (BSC10), has been synthesized and its interfacial hydrogen bond formation or molecular recognition with barbituric acid was investigated in comparison with that of a single chain Schiff base, 2-hydroxybenzaldehyde-octadecylamine (HBOA). It has been found that while HBOA formed a monolayer at the air/water interface, the bolaform Schiff base formed a multilayer film with ordered layer structure on water surface. When the Schiff bases were spread on the subphase containing barbituric acid, both of the Schiff bases could form hydrogen bonds with barbituric acid in situ in the spreading films. As a result, an increase of the molecular areas in the isotherms was observed. The in situ H-bonded films could be transferred onto solid substrates, and the transferred multilayer films were characterized by various methods such as UV-vis and FT-IR spectrosopies. Spectral changes were observed for the films deposited from the barbituric acid subphase, which supported the hydrogen bond formation between the Schiff bases and barbituric acid. By measuring the MS-TOF of the deposited films dissolved in CHCl3 solution, it was concluded that a 2:1 complex of HBOA with barbituric acid and a 1:2 complex of BSC10 with barbituric acid were formed. On the other hand, when the multilayer films of both Schiff bases were immersed in an aqueous solution of barbituric acid, a similar molecular recognition through the hydrogen bond occurred. A clear conformational change of the alkyl spacer in the bolaform Schiff base was observed during the complex formation with the barbituric acid.  相似文献   

14.
研究了竹浆黑液混凝土高效减水剂(GCL1-JB)的结构和吸附特征.将GCL1-JB先通过超滤和离子交换树脂提纯,再通过凝胶柱层析分级,然后选择4种窄分子量分布的GCL1-JB级分进行结构表征和吸附研究.结果表明,GCL1-JB具有高分子量和高磺化度的结构特征.不同分子量级分的GCL1-JB的化学分子结构相似,但其中磺酸基含量随着分子量增大而减少,而芳香环含量随着分子量增大而增大.GCL1-JB在阳离子表面能形成平整的自组装吸附膜,其中高分子量级分的GCL1-JB因磺酸基含量较低,分子较卷曲,故吸附量较大.  相似文献   

15.
This paper describes the buildup of hydrogen-bonding-directed poly(4-vinylpyridine)/poly(4-vinylphenol) (PVPy/PVPh) multilayer film that was fabricated by layer-by-layer (LbL) assembly of PVPy and PVPh from an ethanol solution. UV-visible spectroscopy and Fourier transform infrared (FT-IR) spectroscopy revealed a uniform deposition process. The interaction between PVPy and PVPh was identified as hydrogen bonding through FT-IR spectroscopy and temperature-dependent IR spectral changes of the hydrogen-bonded multilayer. Notably, we discussed the effect of solvent conditions on the growth of PVPy/PVPh multilayer films monitored by UV-visible spectroscopy. It was found that increasing the ratio of N,N-dimethylformamide (DMF) in the mixed ethanol/DMF solvents resulted in a marked decrease of the amount of polymers adsorbed, which was attributed to the increased polarity of the adsorption solutions. Furthermore, the solvent stability of PVPy/PVPh multilayer film in mixed ethanol/DMF solvents with different DMF ratios was also investigated. As a result, a new method for tuning the structure of hydrogen-bonding-directed multilayer film was developed.  相似文献   

16.
Two sulfonated poly(sulphone) sodium salts (SPSF) with different molecular weights and ionic exchange capacities in a N,N-dimethyl formamide/water (DMF-H2O) mixed solvent with various DMF contents were selected as a model system for investigating the influences of solvent composition, solution properties, and charge density of polyelectrolytes on the layer-by-layer (LbL) self-assembly of water-insoluble polyelectrolytes. Poly(dimethyldiallylammonium chloride) (PDDA) in aqueous solution was used as the counterpart. The PDDA/SPSF multilayer films grew nearly linearly with the layer numbers regardless of the volume fraction of DMF, phiDMF, in the SPSF solutions. The total absorption amount of the PDDA/SPSF multilayer films was strongly dependent on the charge density of the SPSF molecules and the phiDMF value of the SPSF solutions. Minimum values of absorption amount were observed at phiDMF = 0.6 to approximately 0.7. The surface hydrophobicity and roughness of the multilayer films can be tuned by varying phiDMF. These observations were rationalized in terms of the chain dimension and the ionization degree of the SPSF molecules as a function of phiDMF, which was characterized by the intrinsic viscosity ([eta]SPSF) and conductivity (LSPSF) of the SPSF solutions. The results indicate that the molecular structures of the DMF-H2O mixed solvent strongly affect the solution properties of SPSF, which in turn determine the growth behavior and physical properties of the PDDA/SPSF multilayer films.  相似文献   

17.
A micropatterned multilayer film, which was fabricated from layer-by-layer electrostatic self-assembly of nitrodiazoresin (NDR)/poly(acrylic acid) (PAA) followed by photolithography, was utilized as a structured template for the biomimetic mineralization of calcium carbonate. Micropatterned CaCO3 films consisting of regularly aligned calcite crystals oriented in the <104> direction were selectively deposited on the patterned NDR/PAA multilayer film.  相似文献   

18.
Multilayer polymer films composed of a ruthenium terpyridine complex containing poly(p-phenylenevinylene) (Ru-PPV) and sulfonated polyaniline (SPAN) were prepared by a layer-by-layer electrostatic self-assembly deposition. The deposition process was carried out from SPAN solution in water and Ru-PPV in dimethylformamide (DMF). Optical-quality multilayer thin films were obtained. The film growth process was monitored by quartz crystal microbalance, and the surface morphology of the films was studied by atomic force microscopy. It was found that the properties of the multilayer films were dependent on deposition conditions such as the pH of the SPAN solution, the presence of salt in the polymer solutions, and the post-film-forming thermal annealing process. Cross-section transmission electron microscopic images suggested that there was no stratified structure formed in the multilayer films. Photovoltaic cells were fabricated by sandwiching the multilayer films between indium-tin-oxide and aluminum electrodes. The device performances were examined by illumination with AM 1.5 simulated solar light. The power conversion efficiencies of these devices were on the order of 10(-3)%. The maximum incident photon-to-electron conversion efficiency (IPCE) of the devices was found to be approximately 2% at 510 nm, which is consistent with the absorption maximum of the ruthenium complex. This indicates that the photosensitization process is due to the electronic excitation of the ruthenium complex.  相似文献   

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