聚吡咯/云母导电复合材料的研究

采用原位聚合的方法制备了聚吡咯(PPy)/云母导电复合材料,并采用十六烷基三甲基溴化铵(CTAB)、聚乙烯基吡咯烷酮(PVP)与1,5-萘二磺酸(1,5-NDA)改性剂对复合材料进行改性.利用透射电子显微镜(TEM)、傅立叶变换红外光谱(FTIR)仪、四探针电导率测试仪分别对复合材料的形貌、结构及导电性能进行测试分析.结果表明,利用改性剂改性后复合材料的电导率有了明显的提高,其中1,5-NDA改性的PPy/云母复合材料的电导率最高,可达4 S/cm.     

PA/CNTs复合材料的电性能研究

采用共沉淀法制备了尼龙6(PA6)/碳纳米管(CNTs)复合材料,研究了该复合材料的电性能。结果表明,CNTs的质量分数为5%时,复合材料的电导率由纯PA6的1×10-15S/cm提高到2.1×10-5S/cm,比纯PA6提高了10个数量级;CNTs的质量分数为15%时,复合材料的电导率为0.13S/cm,比纯PA6提高了14个数量级。在所研究的温度范围内,该复合材料表现出负电阻温度系数效应。当CNTs的质量分数为15%时,复合材料的伏安特性曲线非线性明显,符合半导体特性。     

聚苯胺/纳米石墨复合材料的原位制备与导电性能研究

采用原位聚合法制备了聚苯胺/纳米石墨微片（PANI/NanoG）导电复合材料。结果表明,NanoG的直径约为1~20 μm,厚度为30~90 nm,径厚比为300~500;PANI均匀覆盖在NanoG表面;当NanoG体积含量为2.30 %时,复合材料电导率达到5.16 S/cm,其渗滤阈值达到2.30 %,NanoG的高比表面积及在PANI中的分散造就了复合材料良好的导电性能。     

塑料改性用有机膨润土制备技术及应用的研究

本文采用不同的有机改性剂制备出有机膨润土(OMMT),并用所制备的有机膨润土分别制备出PU/OMMT、PBT/OMMT、PA6/OMMT纳米复合材料.经对复合材料力学性能分析结果表明:用N-烷基氨基酸改性膨润土所制备PU/OMMT、PA6/OMMT纳米复合材料性能最佳;用十六烷基三甲基溴化铵改性膨润土所制备PBT/OMMT纳米复合材料性能最佳.     

原位聚合制备尼龙6/改性氢氧化镁纳米复合材料及其性能的研究

对纳米氢氧化镁(NMH)进行硅烷KH570接枝改性后,将甲基丙烯酸甲酯(MMA)与之共聚获得表面改性的纳米氢氧化镁(MNMH),然后在催化剂作用下原位聚合制备PA 6/MNMH纳米复合材料。利用FTIR、SEM、热重分析和电子拉力机对NMH及PA 6/MNMH纳米复合材料的结构与性能进行测试与表征。红外光谱分析表明改性的NMH表面成功接枝了KH570和聚甲基丙烯酸甲酯(PMMA)。PA 6/NMH-KH570-PMMA复合材料的缺口冲击强度比PA 6/NMH纳米复合材料的提高34%。NMH或其改性NMH的加入提高了PA 6纳米复合材料的热稳定性。     

PVC/改性纳米CaCO3复合材料的制备及性能

合成了纳米CaCO3表面改性剂AP-01,将此改性剂改性的纳米CaCO3用于硬质聚氯乙烯(PVC)抗冲改性.观察PVC/改性纳米CaCO3复合材料的微观结构,并测试其力学性能.结果表明:改性纳米CaCO3以海岛结构分散于PVC基体中.改性纳米CaCO3加入量在10%时,复合材料缺口冲击强度达到18.2 kJ/m2,而复合材料拉伸强度几乎没有改变.对比普通硬脂酸改性纳米CaCO3增韧PVC,其具有明显的性能优势.     

GS改性氧化石墨烯/聚苯胺防腐材料的制备及性能

用双子表面活性剂(GS)通过静电作用对氧化石墨烯(GO)进行插层改性制备了改性氧化石墨烯(GSGO),再以苯胺(An)为单体,过硫酸铵(APS)为引发剂,通过原位聚合法制备了GSGO/PANI复合材料。最后利用GSGO/PANI与水性醇酸树脂(WAR)共混得到了GSGO/PANI/WAR防腐涂层。采用FTIR,Raman,XRD和SEM等测试手段对GSGO和复合材料的形貌、结构进行了表征,结果表明,GS插入到GO的片层中,使得GSGO的层间距增大,且棒状的聚苯胺分散在GO的片层中,形成片状插层结构。动电位极化和电化学阻抗谱测试表明,GSGO/PANI/WAR 复合涂层比纯WAR涂层具有更高的耐腐蚀性能。当复合涂层中w(GSGO)=10% 时,涂层的耐腐蚀性能最好。腐蚀电流密度从9.82?10-6A/cm2减小至1.08?10-6A/cm2,腐蚀电从-0.56V增加到-0.28V,|Z|值可达到5.25?106 ohm.cm2。     

酚醛树脂改性纳米蒙脱土填充PA6的制备及性能研究

分别利用经十八烷基三甲基氯化铵(OTAC)、酚醛树脂(PF)表面改性的纳米蒙脱土(MMT)填充聚酰胺(PA)6,研究了不同表面改性剂及其用量对PA6的力学性能、热性能和吸水性的影响。结果表明,经OTAC改性的纳米MMT和经PF改性的纳米MMT对PA6的热性能改善效果有限,但有利于提高PA6的刚性和降低吸水性。PF改性纳米MMT对PA6的改性效果优于OTAC改性纳米MMT,当PF改性纳米MMT的质量分数为3%时,材料的拉伸强度、弯曲强度和维卡软化温度分别比纯PA6提高了12.3%、58.8%和2%,吸水率降低0.5%。     

PA6/蒙脱土纳米复合材料的力学性能研究

利用未改性蒙脱土和两种季胺盐改性蒙脱土与尼龙(PA)6混合,成功制备得到了不同结构的PA6/蒙脱土纳米复合材料.X射线衍射图谱和力学性能分析表明,季胺盐改性剂可以插入蒙脱土片层之间,使蒙脱土片层扩张,层间距增大.与PA6相比,制备得到的三种纳米复合材料的力学性能都有不同程度的提高.改性蒙脱土与PA6表现出良好的相容性,...     

原位聚合法制备PANI/RGO导电复合材料的性能

采用原位聚合法制备聚苯胺(PANI)、PANI/氧化石墨烯(GO)复合材料和PANI/还原氧化石墨烯(RGO)复合材料。利用四探针测试仪、X射线衍射(XRD)仪、傅立叶变换红外光谱(FTIR)仪、热重(TG)分析仪和扫描电子显微镜(SEM)等对PANI及PANI/GO复合材料和PANI/RGO复合材料进行表征。电导率测试结果表明,当加入GO质量分数为50%时,先还原后聚合法制得PANI/RGO复合材料的导电率可达9.916 S/cm,RGO能有效提高复合材料的导电性;XRD和FTIR分析结果表明,GO和RGO都能较好分散在PANI中;TG分析结果表明,将GO还原为RGO后在小于250℃时能有效提高复合材料的热稳定性。通过原位聚合法能将GO和RGO较好分散在PANI中,形成较好的插层型复合材料,尤其是先还原后聚合法制得的PANI/RGO复合材料具有较好的导电性和热稳定性。     

Preparation and characterization of graphite oxide/polypyrrole composites

Graphite oxide (GO)/polypyrrole (PPy) composites (GPs) and 1,5-naphthalene disulfonic acid (1,5-NDA) doped GPs (1,5-NGPs) have been successfully synthesized via in situ polymerization of pyrrole on GO. The conductivity of 1,5-NGPs is as high as 7 S/cm, seven orders of magnitude higher than that of pristine GO. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) results show PPy “dressed” on the surface of GO layers, while Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analyses confirm the interaction between GO and PPy. The results of thermogravimetric analysis (TGA) and heat treatment at 1000 °C show that the “dressed” PPy on the surface of GO layers in GPs and 1,5-NGPs has effectively prevented the deflagration of GO.     

Morphology and electric conductivity controlling of in situ polymerized poly(decamethylene dodecanoamide)/polyaniline composites

In situ polymerization was proved to be an effective method to prepare composites with combined properties of two intrinsic different components. In this study, poly(decamethylene dodecanoamide) (polyamide 1012, PA1012) powders with controlled morphologies and crystal forms were obtained by antisolvent precipitation, whose morphology and crystal forms were strongly dependent on the types and temperatures of antisolvents. PA1012/polyaniline (PA1012/PANI) composites with different morphologies were manufactured through in situ polymerization. Fourier transform infrared spectroscopy results revealed a strong interaction between PA1012 and PANI components. PANI components were in situ polymerized from aniline monomers on the surface of PA1012 powders, forming a composite aggregates in solution. The conductivity of different PA1012/PANI composite powders was about 10⁻⁵–10⁻³ S/cm, which could successfully meet the requirement of antistatic coating. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47041.     

In situ polymerization approach to multiwalled carbon nanotubes-reinforced nylon 1010 composites: Mechanical properties and crystallization behavior

A series of polyamide 1010 (PA1010 or nylon 1010) and multiwalled carbon nanotubes (MWNTs) composites were prepared by in situ polymerization of carboxylic acid-functionalized MWNTs (MWNT-COOH) and nylon monomer salts. Mechanical tensile tests and dynamic mechanical analysis (DMA) show that the Young modulus increases as the content of the nanotubes increases. Compared with pure PA1010, the Young's modulus and the storage modulus of MWNTs/PA1010 in situ composites are significantly improved by ca. 87.3% and 197% (at 0 °C), respectively, when the content of MWNTs is 30.0 wt%. The elongation at break of MWNTs/PA1010 composites decreases with increasing proportion of MWNTs. For the composites containing 1.0 wt% MWNTs, the Young modulus increases by ca. 27.4%, while the elongation at break only decreases by ca. 5.4% as compared with pure PA1010 prepared under the same experimental conditions. Compared with mechanical blending of MWNTs with pure PA1010, the in situ-prepared composites exhibit a much higher Young's modulus, indicating that the in situ polycondensation method improves mechanical strength of nanocomposites. Scanning electron microscopy (SEM) imaging showed that MWNTs on the fractured surfaces of the composites are uniformly dispersed and exhibit strong interfacial adhesion with the polymer matrix. Moreover, unique crystallization and melting behaviors for MWNTs/PA1010 in situ composites are observed using a combination of differential scanning calorimetry (DSC) and X-ray diffraction methods. It was shown that only the α-form crystals are observed in our MWNTs/PA1010 in situ composites. This result is quite different from PA1010/montmorillonite and PA6-clay composites, where both of α- and γ-form crystals were found.     

Synthesis and characterization of multi-walled carbon nanotubes reinforced polyamide 6 via in situ polymerization

Polyamide 6 (PA6)/carbon nanotubes (PA6/CNTs) composites have been prepared by in situ polymerization of ε-caprolactam in the presence of pristine and carboxylated multi-walled carbon nanotubes (MWNT and MWNTCOOH). Viscosity measurements show that adding 0.5 wt% of carbon nanotubes (CNTs) does not affect the molecular weight of PA6. Compared with pure PA6, the yield strength of PA6/CNTs composites loaded with 0.5 wt% CNTs is almost unchanged, and the tensile strength is increased slightly. Dynamic mechanical analysis (DMA) demonstrates that both the storage modulus (E′) and glass transition temperature (T_g) of the PA6/CNTs composites increase, particularly for PA6/MWNTCOOH, indicating there is some chemical bonding between PA6 and MWNTCOOH. Scanning electron microscopy (SEM), transmission electron microscopy (TEM) and ultra small-angle X-ray scattering (USAXS) show that MWNT and MWNTCOOH are well dispersed in PA6 matrix. Comparison of the USAXS data with a stiff-rod model and wormlike rod model reveals that the CNTs are quite flexible, regardless the degree of chemical modification. Due to the flexibility of CNTs, mechanical properties of the PA6/CNTs composites are marginally enhanced.     

聚苯胺/SnO2复合材料的制备及其光催化应用

用光化学合成SnO<,2>为主要原料,在酸性苯胺溶液中,通过苯胺在SnO<,2>粒子表面原位聚合,制备了聚苯胺/SnO<,2>复合材料.用XRD、SEM和紫外-可见漫反射(UV-Vis)等对复合材料进行了表征.以甲基橙为目标污染物,考察了聚苯胺/SnO<,2>复合材料光催化障解污染物的性能.结果表明,含适量聚苯胺(PA...     

Fabrication and electrochemical characterization of polyaniline nanorods modified with sulfonated carbon nanotubes for supercapacitor applications

The novel composites of sulfonated multi-walled carbon nanotubes (sMWCNTs) modified polyaniline (PANI) nanorods (PANI/sMWCNTs) were synthesized successfully by in situ oxidative polymerization method in the HClO₄ solution. FTIR and Raman spectra revealed the presence of π–π interaction between the PANI and the sulfonated carbon nanotubes and the formation of charge transfer composites. It was found that the specific capacitance of the PANI/sMWCNT composites was markedly influenced by their morphological structure and the content of PANI which was coated onto the sMWCNT. The specific capacitance of the PANI/sMWCNT composite exhibited a maximum value of 515.2 F g⁻¹ at the 76.4 wt% PANI. The charge–discharge tests showed the PANI/sMWCNT composites possessed a good cycling stability (below 10% capacity loss after 1000 cycles) compared to PANI nanorods.     

Enzyme‐Catalyzed Synthesis of Conducting Polyaniline Nanocomposites with Pure and Functionalized Carbon Nanotubes

The in situ enzymatic polymerization of aniline onto multi‐walled carbon nanotubes (MWCNT) and carboxylated MWCNT (COOH‐MWCNT) is reported. Nanostructured composites were prepared by this method. Polymerization was catalyzed with the enzyme horseradish peroxidase at room temperature in aqueous medium of pH 4. Hydrogen peroxide was used in low concentration as the oxidant. The nanocomposites were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and thermogravimetric analysis (TGA). The TEM studies showed tubular morphology with uniformly distributed MWCNT in the nanocomposites. The SEM and TEM investigations revealed wrapping of the MWCNT with polyaniline (PANI) chains. TGA demonstrated that the PANI component is thermally more stable in PANI/COOH‐MWCNT compared to the PANI/MWCNT composites. The synthesized nanocomposites showed higher conductivity than pure PANI, which may be due to the strong interaction between the PANI chains and the MWCNT.     

Hollow nitrogen-containing core/shell fibrous carbon nanomaterials as support to platinum nanocatalysts and their TEM tomography study

Core/shell nanostructured carbon materials with carbon nanofiber (CNF) as the core and a nitrogen (N)-doped graphitic layer as the shell were synthesized by pyrolysis of CNF/polyaniline (CNF/PANI) composites prepared by in situ polymerization of aniline on CNFs. High-resolution transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared and Raman analyses indicated that the PANI shell was carbonized at 900°C. Platinum (Pt) nanoparticles were reduced by formic acid with catalyst supports. Compared to the untreated CNF/PANI composites, the carbonized composites were proven to be better supporting materials for the Pt nanocatalysts and showed superior performance as catalyst supports for methanol electrochemical oxidation. The current density of methanol oxidation on the catalyst with the core/shell nanostructured carbon materials is approximately seven times of that on the catalyst with CNF/PANI support. TEM tomography revealed that some Pt nanoparticles were embedded in the PANI shells of the CNF/PANI composites, which might decrease the electrocatalyst activity. TEM-energy dispersive spectroscopy mapping confirmed that the Pt nanoparticles in the inner tube of N-doped hollow CNFs could be accessed by the Nafion ionomer electrolyte, contributing to the catalytic oxidation of methanol.