聚吡咯/凹凸棒纳米复合材料对Cr6+的吸附性能

以FeCl3为氧化剂和掺杂剂用原位聚合法制备了聚吡咯/凹凸棒纳米复合材料,用以吸附溶液中高毒性的Cr6+。研究表明,该吸附剂在10min内即可达到吸附平衡,吸附效果优异,同时考察了吸附剂用量、Cr6+的初始浓度和pH值对吸附效果的影响。吸附过程等温线数据符合Langmuir等温吸附方程式,饱和吸附量为48.45mg/g,计算得到的热力学数据ΔH、ΔG、ΔS均为负值,说明该吸附过程是一个放热的自发过程。吸附动力学符合准二级动力学方程,说明吸附过程属于化学吸附反应过程。用傅里叶变换红外光谱和扫描电镜对复合材料的结构进行表征,发现聚吡咯微球包覆在棒状的凹凸棒表面形成纳米复合材料,其红外谱图与聚吡咯基本一致。     

聚吡咯/凹凸棒石水性导电涂料的制备

用吡咯单体(Py)在凹凸棒石(ATP)的表面发生原位聚合反应,制备出聚吡咯/凹凸棒石(PPy/ATP)纳米导电复合材料.通过Fourier红外光谱、X射线衍射、扫描电子显微镜对复合材料进行表征,结果表明聚吡咯的包覆没有破坏凹凸棒石的晶体结构,两者之间作用仅为物理作用.以PPy/ATP为填料制备的水性丙烯酸涂料导电性高于以PPy为填料制备的水性丙烯酸涂料,并通过SEM研究了涂层的导电机理,表明PPy/ATP在导电涂料中具有更为广阔的应用前景.     

炭黑吸附聚合制备聚吡咯/ 炭黑导电复合材料

用炭黑吸附化学氧化聚合法制备聚吡咯/ 炭黑( PPy/ C) 导电复合材料。运用FT2IR、TGA、SEM、四探针和电化学测试仪对材料的组成、结构和性能进行了测试和表征。导电炭黑的加入不仅提高了材料的电导率,由原来的6.152 S/ cm 增加至13.42 S/ cm, 而且提高了材料的堆积密度, 改善了聚吡咯的颗粒形态和制膜加工性能, 聚吡咯复合材料为正极的锂/ 聚吡咯二次电池的性能得以改善, 室温下充放电循环30 次以上, 电池容量无明显衰减, 库仑效率在98 %以上, 首次放电容量以聚吡咯计可达41 mAh/ g。      

木质素-聚吡咯复合纳米粒子的制备及其Ag+吸附性能

以酶解木质素和吡咯单体为原料,通过原位聚合法制备了木质素-聚吡咯(EHL-PPY)复合纳米粒子。而后以银离子为吸附质,系统地研究了EHL-PPY复合纳米粒子的银离子吸附性能,考察了吸附剂浓度,吸附时间和银离子初始浓度对吸附容量和吸附率的影响。在35℃时,该复合纳米粒子对银离子的饱和吸附容量为882.0 mg/g,吸附完成后,银离子被还原为直径为22~56 nm的单质银颗粒。研究表明,EHL-PPY复合纳米粒子可作为低成本银离子吸附剂使用。     

聚吡咯纳米复合材料的研究进展

聚吡咯具有较大的比电容、较高的电导率、较好的化学稳定性等诸多优点,被认为是最有可能实现工业化生产的导电聚合物。然而,常规块状聚吡咯通常在电学、光学和生物学特性方面存在不足,而纳米结构聚吡咯由于明确的纳米结构和更大的表面积,具有特殊的电化学活性、改善的光学性能和良好的生物相容性。此外,面对日新月异的科技发展,单一的聚吡咯纳米材料已经不足以应对各方面的应用需求,而聚吡咯纳米复合材料保留了单个组分的功能以及与其他功能材料集成时的协同效应,可以同时具备几种材料各自的优点,从而大大拓宽聚吡咯的应用范围。本文综述了聚吡咯纳米复合材料的研究进展,介绍了五种类型的聚吡咯纳米复合材料,基于其优异的导电性和可逆的氧化还原等性能,结合近几年的文献,介绍了聚吡咯纳米复合材料在储能、生物医学、吸附和杂质去除、电催化、吸波材料、传感器和腐蚀防护领域的应用,最后展望了这一研究领域目前所面临的挑战和机遇。     

聚乙烯吡咯烷酮掺杂聚吡咯对灿烂绿吸附性能的研究

采用原位聚合法制备了聚乙烯吡咯烷酮掺杂的聚吡咯,对聚吡咯的结构进行了表征。研究了聚吡咯作为吸附剂对灿烂绿的吸附性能,探讨了吸附剂用量、温度、时间及灿烂绿起始浓度对吸附效果的影响。在灿烂绿溶液50mL初始浓度为90mg/L,聚吡咯用量为0.10g,吸附时间为90min,温度为25℃条件下,聚吡咯对灿烂绿的吸附量为42.03mg/g。吸附动力学分析表明吸附过程为化学吸附,等温吸附规律符合Freundlich模型。聚吡咯对灿烂绿的吸附是自发过程。     

TiN/聚吡咯纳米复合材料的制备及表征

采用氨解法制备了纳米氮化钛(TiN)粉体,对纳米TiN粉体进行表面改性,使其均匀分散到吡咯单体中.采用原位聚合法制备了TiN/聚吡咯(PPy)纳米复合材料.对合成的复合材料用X射线衍射(XRD)、透射电镜(TEM)、傅立叶变换红外光谱(FT-IR)、四探针测试仪等方法进行了表征与检测.结果表明:PPy成功地包覆在TiN纳米颗粒表面,形成了纳米TiN/PPy复合材料.复合材料具有优良的电性能.     

水基阳离子聚氨酯/聚吡咯导电材料的原位制备与电阻性能

以N-甲基二乙醇胺(MDEA)为扩链剂,聚乙二醇(PEG1000)、异佛尔酮二异氰酸酯(IPDI)为原料,通过预聚体法制备了系列水基阳离子聚氨酯分散液(CWPU)。再以FeCl3为氧化剂,在CWPU中进行吡咯的原位化学氧化聚合制备聚氨酯/聚吡咯(CW-PU/PPy)复合导电材料。红外光谱图表明PPy与CWPU分子间存在氢键缔合。经PPy改性后,CW-PU/PPy的分散液的平均粒径由10.61nm增加至30.29nm,粒径分布系数由0.850下降至0.346。原位聚合过程中PPy能均匀包裹于CWPU胶粒表面,CWPU/PPy分散液胶粒呈球形结构,彼此间相互独立。实验结果亦表明,当Py浓度为20%、反应温度为40℃、反应时间为2h、n(FeCl3)/n(Py)=2.0时,CWPU/PPy复合薄膜的表面电阻率可达到20Ω.cm。     

聚吡咯纳米复合材料的研究进展

聚吡咯纳米复合物作为一种新型材料,有着十分广阔的应用前景。本文介绍了聚吡咯纳米复合材料的最新进展,从聚吡咯纳米复合材料的分类、制备方法及应用领域等几个方面进行了综述,并对聚吡咯复合材料的发展前景进行了展望。     

添加剂对聚吡咯/氧化石墨纳米复合材料结构和性能的影响

采用单体原位聚合法制备了三种聚吡咯/氧化石墨纳米复合材料。通过XRD、FT-IR和TEM对产物进行结构表征,探讨了未加添加剂及分别以N aOH和十二烷基苯磺酸钠为添加剂制得的聚吡咯/氧化石墨纳米复合材料的结构与性能的差别。结果表明,未加添加剂和以N aOH为添加剂时产物为非晶态的剥离型聚吡咯/氧化石墨纳米复合材料;而以十二烷基苯磺酸钠为添加剂时可得到具有层状有序结构的插层型聚吡咯/氧化石墨纳米复合材料。插层型聚吡咯/氧化石墨纳米复合材料的导电和电化学性能优于剥离型聚吡咯/氧化石墨纳米复合材料,它们的提高归因于聚吡咯分子链共轭程度的增加。     

魔芋葡甘聚糖/凹凸棒土复合膜的制备与表征

采用天然纳米粘土——凹凸棒土(AT)对魔芋葡甘聚糖(KGM)进行共混改性,并通过流延成膜的方法制备了KGM/AT纳米复合材料,采用X射线衍射(XRD)、傅里叶红外光谱(FT-IR)、扫描电镜(SEM)对复合材料的结构和形貌进行表征;利用热重分析(TG)、力学性能测试、溶胀性测试分别研究了复合材料的热稳定性、机械性能以及耐水性能。结果表明,AT与KGM之间可以通过氢键产生较强的相互作用,AT在一定程度上可以促进KGM结晶,适量的AT在KGM基体中可以均匀分散,而过量的AT则易发生团聚,在基体中无规分布。复合材料的起始分解温度和最快分解温度明显提高,材料的热稳定性增强。此外,随着AT的加入,复合材料的力学性能和耐水性能也得到了一定程度的改善。     

Synthesis and properties of waterborne polyurethane/attapulgite nanocomposites

The novel nanocomposites derived from waterborne polyurethane (WPU)/Attapulgite (AT) nanocomposites have been successfully synthesized by in situ polymerization progress. AT functionalized by chemical modification were incorporated as a crosslinker in prepolymer. The chemical structures, morphology, thermal behavior, and mechanical properties of the WPU/AT nanocomposites were investigated by Fourier transform infrared spectroscopy (FTIR), thermo gravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), X-ray diffraction (XRD) and tensile testing respectively. The experimental results indicated that the organically modified attapulgites were homogeneously dispersed in the WPU and resulted in an improvement of thermal stability, tensile strength and elongation at break of WPU/AT nanocomposites.     

Novel nanocomposites based on gelatin/HPET/chitosan with high performance acid red 150 dye adsorption

In this study, the properties of gelatin and chitosan are combined in the presence of hydrolyzed poly(ethylene terphthalate), HPET, and laponite to produce a novel hybrid natural-synthetic material for anionic dyes removal applications. Adsorption studies of acid red 150 from aqueous solution with respect to the initial dye concentration, temperature, time, pH, and sorbent dosage were investigated. The Langmuir adsorption model was applied to describe the equilibrium isotherms. The prepared nanocomposites were characterized using different techniques, such as FTIR, DSC, SEM, and TEM. The suitability of the adsorbent was tested by fitting the adsorption data with Langmuir isotherm. The results showed that the adsorption of AR150 was increased with an increasing in both of the dye and chitosan concentrations.     

Synthesis and characterization of novel hyperbranched polyimides/attapulgite nanocomposites

Novel hyperbranched polyimides/attapulgite (HBPI/AT) nanocomposites were successfully synthesized by in situ polymerization. HBPI derived from novel 2,4,6-tri[3-(4-aminophenoxy)phenyl]pyridine (TAPP) and 2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl]propane dianhydride (BPADA). 4,4′-diphenylmethane diisocyanate (MDI) modified AT copolymerized with HBPI and the nanocomposites formed multilinked network. Chemical structure, morphology, thermal behavior, and mechanical properties of nanocomposites were investigated by Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), thermal gravimetric analysis (TGA), dynamic mechanical analysis (DMA), and tensile testing et.al. Results indicated that modified AT was homogeneously dispersed in matrix and resulted in an improvement of thermal stability, mechanical properties and water resistance of HBPI/AT nanocomposites.     

Electromagnetic absorption efficiency of polypropylene/montmorillonite/polypyrrole nanocomposites

Electrical conductivity and dielectric properties have been studied for two types of polypropylene composites containing conducting phase. One type comprised conducting polymer–polypyrrole while the second employed montmorillonite particles coated with conducting polymer–polypyrrole. Composites’ shielding properties were estimated based on their previously determined electromagnetic characteristics. Unlike a basic binary polypropylene/polypyrrole composite, the ternary sample with multicomponent montmorillonite particles exhibits higher dielectric losses and consequently a significant rise in shielding efficiency in the radio-frequency range of 0.1–1.5 GHz. This stems from the presence of highly polarizable multicomponent montmorillonite anisotropic lamellar particles with polypyrrole conducting layer, which considerably increases the complex permittivity of the composite.     

Double corrosion protection mechanism of molybdate-doped polypyrrole/montmorillonite nanocomposites

Nanocomposites based on polypyrrole (PPy) doped with molybdate (PPy(MoO₄)) and montmorillonite (MMT) were prepared by chemical polymerisation. The morphology of nanocomposite particles was studied by scanning electron microscopy. The chemical structure of conducting polymers (CPs) in nanocomposites was characterised by Raman spectroscopy. The thermal analysis showed that all CPs in the nanocomposites were stable for more than 500°C. Energy diffraction X-ray showed that the amount of Mo in element the PPy(MoO₄)/MMT nanocomposite was 5.55%. The corrosion protection mechanism of the nanocomposites was investigated by electrochemical methods, showing that MMT acted as a barrier layer in nanocomposite and molybdate as an inhibitor for corrosion protection of metal.     

PPy/ZnO复合材料的电化学制备与性能研究

以草酸和十二烷基苯磺酸为电解质,利用电化学方法,基于不同的基底(如镍片、不锈钢网和碳布)制备了聚吡咯/氧化锌(PPy/ZnO)纳米复合材料,并对其进行了表征和性能分析。结果表明基于镍片的复合材料中,聚吡咯呈典型的菜花状结构,ZnO颗粒夹杂在聚吡咯颗粒中;而基于不锈钢网和碳布的复合材料中,聚吡咯呈不均匀的片状结构,ZnO颗粒夹杂在聚吡咯薄片之间,这可能与衬底的网状结构有关。研究还发现基于碳布的PPy/ZnO复合材料具有较好的电荷容纳能力,而基于镍片和不锈钢网的PPy/ZnO复合材料的氧化还原可逆性都较差,电化学交换反应比较困难,而且容纳电荷的能力也较弱。     

Adsorption of a cationic dye (methylene blue) onto spent activated clay

The adsorption characteristics of methylene blue (MB) onto spent activated clay (SAC), a waste produced from an edible oil manufacturer was investigated. Results showed that the adsorption increased with increasing MB concentration, temperature, and pH. The adsorption equilibrium data was well fitted by multilayer adsorption isotherm. The maximum adsorption capacities for MB ranged from 0.94x10(-4) to 3.41x10(-4)mol/g between 5 and 45 degrees C. Thermodynamic parameters suggest that the adsorption is spontaneous and endothermic. We proposed a modified double exponential equation accounting both with chemical and mathematical point of view to describe the adsorption kinetic data. The increases of mass transfer and adsorption capacity were mainly attributed to the interlayer of the SAC expanding at higher temperature. An activation energy of 13.5 kcal/Kmol was determined suggesting that the adsorption involved a chemical reaction mechanism.