反应条件对原位聚合法制备PANI/CIP复合材料的影响

采用原位聚合法制备了核壳结构的聚苯胺(PANI)/羰基铁粉(CIP)复合材料,考察了掺杂酸种类、盐酸浓度、CIP用量、预搅拌时间等反应条件对反应过程及复合材料形貌和电导率的影响.以盐酸和对甲基苯磺酸为掺杂酸,均可得到核壳结构的PANI/CIP复合材料,但掺杂盐酸时综合效果较好.盐酸浓度为0.15 mol/L时制备PAN...     

PVP对原位沉积PANI/PI结构和导电性的影响

采用分散聚合体系,在聚酰亚胺(PI)基体表面原位沉积聚苯胺(PANI)制备高导电的PANI/PI/PANI复合膜.结果表明,空间稳定剂聚乙烯吡咯烷酮(PVP)对PANI粒子的稳定效应主要对大粒子起稳定作用;基体表面致密膜层主要由PANI小粒子堆砌形成.基体表面为质子酸(盐酸)掺杂的PANI膜层,膜中不含有PVP.采用高相对分子质量PVP作为稳定剂、增大PVP浓度可使复合膜表面结构致密.     

Preparation and anticorrosive properties of PANI/Na-MMT and PANI/O-MMT nanocomposites

Nanocomposites of polyaniline (PANI) with organophilic montmorillonite (O-MMT) and hydrophilic montmorillonite (Na-MMT) were prepared. The nanocomposites were characterized using FT-IR, D.C. electrical conductivity measurement and cyclic voltammetry techniques. It was found that PANI/Na-MMT nanocomposite has lower (5.8%) and PANI/O-MMT nanocomposite has higher (29.4%) conductivity compared to pure polyaniline. Cyclic voltammetry experiments showed that both nanocomposites are electroactive. The anticorrosive properties of a 100 μm thickness coating of nanocomposites on iron coupons were evaluated and compared with pure polyaniline coating. According to the results PANI/MMT nanocomposites have enhanced corrosion protection effect in comparison to pure polyaniline coating. Results showed also that the PANI/Na-MMT and PANI/O-MMT nanocomposites have considerably different corrosion protection efficiencies in various corrosive environments.     

Microwave electromagnetic properties of polyimide/carbonyl iron composites

A facile and effective approach was developed to fabricate dual temperature- and pH-sensitive hollow nanospheres utilizing an atom transfer radical polymerization (ATRP) method. To do this silica nanoparticles were used as primary cores that could be etched by an hydrofluoric (HF) aqueous solution. Due to uncontrolled ATRP of acrylic acid (AA) methyl acrylate (MA) was polymerized via surface-initiated ATRP (SI-ATRP) a and poly(2-hydroxyethyl methacrylate) (PHEMA) block was added via the same approach. To synthesize poly(AA-co-HEMA)-grafted silica nanoparticles polymethyl acrylate (PMA) chains were hydrolyzed to polyacrylic acid (PAA) using an aqueous NaOH solution. PAA segments were partially crosslinked via an esterification reaction of –COOH groups with 1,4-butanediol. Finally, poly(AA-co-HEMA) hollow nanospheres were fabricated by etching silica cores with an HF aqueous solution. The structure of the nanospheres was revealed by transmission electron microscopy (TEM). These hollow nanospheres consisting of poly(AA-co-HEMA) in their structure showed dual pH- and thermo-sensitive properties as measured by dynamic light scattering (DLS). The hydrodynamic diameter was measured as an affected parameter under different pH (3–12) and temperature (25–55 °C) conditions. Results showed that by decreasing pH or by increasing temperature the hydrodynamic diameter decreased and a lower critical solution temperature (LCST) point was observed.     

The synthesis of rGO/RuO2, rGO/PANI,RuO2/PANI and rGO/RuO2/PANI nanocomposites and their supercapacitors

Polymer Bulletin - In this work, reduced graphene oxide (rGO) was obtained by chemical reduction of graphene oxide (GO) using sodium borohydride (NaBH4). Four different nanocomposites rGO/ruthenium...     

The influence of layered compounds on the properties of starch/layered compound composites

Glycerol‐plasticized starch films were modified by addition of various layered compounds as fillers, two being of natural origin (kaolinite, a neutral mineral clay, and hectorite, a cationic exchanger mineral clay) and two synthetic (layered double hydroxide, LDH, an anionic exchanger, and brucite, having a neutral structure). The effects of the filler type and the plasticizer were analyzed by X‐ray diffraction, dynamic mechanical analysis and thermogravimetry. The storage modulus was higher for kaolinite > brucite > hectorite than for LDH starch composites. However, only the hectorite filler presented a shift of the interplanar basal distance to higher values, which represents the intercalation of glycerol molecules between the clay layers. The glycerol intercalation is minimized in plasticized–oxidized starch films where the oxidized starch chains are preferentially intercalated. Copyright © 2003 Society of Chemical Industry     

聚苯胺/钡铁氧体的制备及性能研究

分别采用柠檬酸溶胶-凝胶法和原位聚合法制备了钡铁氧体粒子和聚苯胺-钡铁氧体复合物。利用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、四探针测试仪等分析手段表征了复合材料的结构,观察了其形貌,测试了其性能。结果表明,钡铁氧体粒子为M型六角晶系片状晶相结构,粒径在10μm～50μm。聚苯胺/钡铁氧体复合材料的电导率随钡铁氧体含量的增加而下降,当BaFe12O19质量分数增加到10%时,电导率从8.85×10-2S/cm急剧下降到2.98×10-2S/cm。而后,随着钡铁氧体含量的增加,电导率变化不大。     

PANI/N-K2Ti4O9/UiO-66复合材料的制备及光催化性能研究

用自组装法将金属有机框架UiO-66负载到低带隙半导体N-K2Ti4O9的表面,然后采用原位氧化复合法制备导电聚合物聚苯胺粘结的PANI/N-K2Ti4O9/UiO-66复合光催化剂（复合材料A）,制备了N-K2Ti4O9和UiO-66不同比例物理混合后再粘结聚苯胺的复合材料B.采用红外（IR）、场发射透射电镜（FETEM）、荧光光谱（PL）对复合材料的结构、形貌进行表征.结果表明,UiO-66负载到棒状N-K2Ti4O9的表面呈现核壳结构,聚苯胺（PANI）粘结在核壳结构N-K2Ti4O9/UiO-66的表面形成复合材料,PANI粘结可以有效降低电子-空穴复合率,复合材料A具有最好的光催化性能.     

AAS/GPNs电磁屏蔽复合材料的制备及其性能

对石墨烯进行功能化改性,以丙烯腈-丙烯酸丁酯-苯乙烯共聚物(AAS)为基体,采用溶液分散法制备了AAS/功能化石墨烯(GPNs)复合材料,并研究了其性能。结果表明:GPNs与AAS基体融合性和结合力均较好;AAS/GPNs复合材料的耐候性远优于丙烯腈-丁二烯-苯乙烯共聚物/石墨烯复合材料;GPNs用量为0.5%(w)时,复合材料的拉伸强度为52.3 MPa,较纯AAS提高了36%;电磁波频率为2~18 GHz时,复合材料的电磁屏蔽效能均大于20 dB,能够满足商业产品的需求。     

PANI/N-K_2Ti_4O_9/UiO-66复合材料的制备及光催化性能研究

用自组装法将金属有机框架UiO-66负载到低带隙半导体N-K2Ti4O9的表面,然后采用原位氧化复合法制备导电聚合物聚苯胺粘结的PANI/N-K2Ti4O9/UiO-66复合光催化剂(复合材料A),制备了N-K2Ti4O9和UiO-66不同比例物理混合后再粘结聚苯胺的复合材料B。采用红外(IR)、场发射透射电镜(FETEM)、荧光光谱(PL)对复合材料的结构、形貌进行表征。结果表明,UiO-66负载到棒状N-K2Ti4O9的表面呈现核壳结构,聚苯胺(PANI)粘结在核壳结构N-K2Ti4O9/UiO-66的表面形成复合材料,PANI粘结可以有效降低电子-空穴复合率,复合材料A具有最好的光催化性能。     

Effects of the interaction between siloxane hydrolysate and PANI on the properties of PANI/SiO2 hybrid materials

PANI/SiO₂ Hybrids were synthesized via a sol‐gel process using tetramethoxysilane (TMOS), γ‐glycidoxypropyltrimethoxysilane (GPTMS), and 3‐(trimethoxysily1)propyl methacrylate (MSMA) as precursors, respectively. The effect of the interaction between siloxane hydrolysate and PANI on the microstructure and properties of the PANI/SiO₂ Hybrid Materials was studied using scanning electron microscopy, Fourier‐transform infrared, UV–vis, ¹H NMR, thermo gravimetric analysis, and potentiodynamic polarization analysis. Experiment results demonstrated that, an appropriate interaction between siloxane hydrolysate and PANI is useful to achieve a homogeneous and stable hybrid. The weak interaction between silanols and PANI will cause the phase separation between siloxane hydrolysate and PANI, whereas the strong interaction may lead to the formation of bulk materials and precipitation. In comparison with TMOS and MSMA, more hydrogen bonds are formed in the PANI/SiO₂ hybrid materials using GPTMS as precursor, which make it have a homogeneous and smooth surface without detectable cracks and present excellent corrosion protection properties. POLYM. COMPOS., 38:657–662, 2017. © 2015 Society of Plastics Engineers     

聚苯胺/NBR复合材料的制备与性能研究

分别采用溶液法和乳液法合成盐酸和十二烷基苯磺酸掺杂的聚苯胺(PANI),研究PANI/NBR复合材料的硫化特性、导电性能和物理性能.结果表明,随着PANI用量的增大,复合材料的MH增大,t10和t90先延长后缩短;掺杂态PANI用量对复合材料的电导率影响较小;随着PANI用量的增大,复合材料的拉伸强度、邵尔A型硬度和100%定伸应力明显增大,拉断伸长率先增大后减小,在PANI为30份时达到最大值.     

High-performance polymer/nanodiamond composites: synthesis and properties

Conjugated polymer/nanodiamond nanocomposites have been known as high-performance materials due to improved physical properties relative to conventional composites. In this attempt, novel conjugated polymer/nanodiamond nanocomposites were successfully prepared by in situ oxidative polymerization. Physical characteristics of the resultant nanocomposites were explored using Fourier transform infrared spectroscopy, field emission scanning electron microscope (FESEM), energy dispersive X-ray spectroscope, differential scanning calorimeter, thermogravimetric analysis and X-ray diffraction spectroscopy. Structural analysis revealed the oxidative polymerization of various matrices [polyaniline (PANi), polypyrrole (PPy), polythiophene (PTh) and polyazopyridine (PAP)] over the surface of functionalized (F-NDs) and non-functionalized nanodiamonds (NF-NDs) thus ensuing NF-NDs/PAP/PANi/PPy, F-NDs/PAP/PANi/PPy, NF-NDs/PANi/PPy/PTh and F-NDs/PANi/PPy/PTh nanocomposites. FESEM images depicted the fibrillar morphology of resulting nanocomposites with granular arrangement of nanofiller in matrix. Thermal analysis results showed that the functionalized F-NDs/PAP/PANi/PPy hybrid had higher value of 10 % weight loss around 489 °C relative to F-NDs/PANi/PPy/PTh with T₁₀ at 471 °C. The glass transition temperature was found to be 99 and 105 °C for NF-NDs/PANi/PPy/PTh and F-NDs/PANi/PPy/PTh, respectively. On the other hand, NF-NDS/PAP/PANi/PPy and F-NDs/PAP/PANi/PPy showed higher T _g’_s of 109 and 118 °C. The conductivity of NF-NDs/PAP/PANi/PPy was 3.8 Scm^?1 and improved with the functionalized filler loading in F-NDs/PAP/PANi/PPy up to 5.4 Scm^?1, while NF-NDs/PANi/PPy/PTh and F-NDs/PANi/PPy/PTh had relatively lower values around 2.9 and 3.7 Scm^?1, respectively. New conducting nanocomposites may act as useful contenders in significant industrial applications such as polymer Li-ion battery.     

Mechanical and dielectric properties of SiCf/SiC composites fabricated by PIP combined with CIP process

2D KD-1 SiC fiber fabrics were employed to fabricate SiC_f/SiC composites by an improved polymer infiltration and pyrolysis (PIP) process, combined with cold isostatic pressing (CIP). The effect of CIP process on the microstructure, mechanical and dielectric properties of SiC_f/SiC composites was investigated. The infiltration efficiency was remarkably improved with the introduction of CIP process. Compared to vacuum infiltration, the CIP process can effectively increase the infiltrated precursor content and decrease the porosity resulting in a dense matrix. Thus SiC_f/SiC composites with high density of 2.11 g cm⁻³ and low porosity of 11.3% were obtained at 100 MPa CIP pressure, together with an increase of the flexural strength of the composites from 89 MPa to 213 MPa. Real part (ε′) and the imaginary part (ε″) of complex permittivity of SiC_f/SiC composites increase and vary from 11.7-i9.7 to 15.0-i12.8 when the CIP pressure reaches 100 MPa.     

The influence of carbon fibre surface treatment on the mechanical properties of carbon/carbon composites

The influence of carbon fibre type and carbon fibre surface treatment on the mechanical properties of phenolic-based, unidirectionally reinforced carbon/carbon composites has been investigated.It was found that only the reinforcement of carbon/carbon composites with untreated type I fibres results in best mechanical properties. Surprisingly in that case also an optimised surface treatment of the fibres improve the yield of fibre strength. The experimental results have shown that the applicability of the rule of mixtures for the precalculation of the strength of carbon/carbon composites is limited and that the fracture behaviour is controlled by the amount of adhesion between carbon fibres and carbon matrix.     

The synthesis of vaterite and physical properties of PP/CaCO3 composites

Vaterite was synthesized in the emulsion state at 50 ‡C. The mixing method was found to have a significant effect on the shape of vaterite. In order to investigate the effect of CaCO₃ morphology on mechanical property and thermal property of polypropylene, cubic forms of calcite and needle forms of aragonite were also prepared in the emulsion states. When vaterite was used as a filler in the PP/CaCO₃ composites, the crystallization temperature and crystallinity were higher than those with other forms. In addition, the size of spherullite of polypropylene was the finest when vaterite was used. Therefore, the vaterite is considered as a proper nucleating agent for polypropylene.     

The influence of plasma treatment on the tribological properties of hybrid PTFE/cotton fabric/phenolic composites

In this study, the effects of air‐plasma and N₂‐plasma treatment on the hybrid polytetrafluoroethylene (PTFE)/cotton fabric and a phenolic resin were investigated in detail. The tribological properties of the untreated and plasma‐treated hybrid PTFE/cotton fabric/phenolic composites were investigated. The results indicated that air‐plasma‐treated hybrid PTFE/cotton fabric/phenolic composites exhibited better antiwear and friction reduction properties. The combination of scanning electron microscopy and Fourier transform infrared spectroscopy analysis illustrated that hybrid PTFE/cotton fabric/phenolic composites treated with air‐plasma possessed more integrated structure and more functional groups, which plausibly contributed to the better tribological properties of the hybrid PTFE/cotton fabric/phenolic composites treated with air‐plasma. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers     

Fabrication of Au/PVP nanofiber composites by electrospinning

Gold nanoparticles prepared by trisodium citrate reduction of HAuCl₄ in poly(vinylpyrrolidone) (PVP) ethanol solution were dispersed into PVP nanofibers by electrospinning. The optical property of Au nanoparticles before and after electrospinning was measured by UV‐Vis. The morphology and distribution of gold nanoparticles in PVP nanofibers were observed by transmission electron microscopy (TEM). The influence of the amount of Au added to and the concentration of PVP in electrospinning solution over the morphology of Au/PVP nanofibers were studied. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

基于PANI/EG层间复合材料的Cd2 电化学传感器

以电化学氧化法制备的膨胀石墨(EG)为碳骨架，采用真空插层辅助原位氧化聚合法，使多孔塔尖状的聚苯胺(PANI)有序包覆生长在EG的石墨片层表面，构建了PANI/EG层间复合材料。采用SEM、TEM、XRD、FTIR、Raman、XPS和BET对PANI/EG复合材料的结构和组成进行表征。以PANI/EG复合材料修饰玻碳电极，采用SWASV法对Cd2 进行检测，通过CV和EIS测试修饰电极的电化学行为。结果表明：PANI/EG复合材料呈层状分级空间结构。EG质量分数为12%的PANI/EG修饰电极对痕量Cd2 检测的敏感度为7.814 μA/μM，检测极限为3.24 nM，检测范围为0.25~6 μM，重复性及抗干扰性良好。