马来酸酐接枝 SEBS对聚丙烯 / 碳纳米管复合材料性能的影响

采用球磨和熔融共混法，制备了聚丙烯（PP）／碳纳米管（CNT）／马来酸酐接枝SEBS（MA－SEBS）复合材料，结果表明，MA－SEBS促进了CNT在PP基体中的分散，形成完善的逾渗网络，改善了PP／CNT复合材料的抗静电性，提高了CNT对PP的增强作用，对PP／CNT复合材料有明显的增韧作用。     

聚丙烯/碳纳米管复合材料的研究进展

聚丙烯（PP）作为通用型热塑性塑料,具有物理性能优异、成型加工简单、密度小以及原料来源丰富等优点,广泛应用于电器、汽车和包装等行业。但是PP具有韧性差、低温脆性突出、抗冲击性能不佳、介电常数低、制品尺寸稳定性差等诸多缺点。碳纳米管（CNT）不仅具有独特的管状结构,还具有优异的力学、导电、导热以及耐磨等性能。将CNT和PP进行复合并制备出具有导电、导热、耐磨等高性能复合材料具有广阔的应用前景。因此,本文重点综述PP和CNT复合材料的新进展,主要包括结晶行为、力学性能、电学性能、摩擦性能、导热性能以及其他性能。针对现阶段PP/CNT复合材料研究和开发过程中存在的问题提出意见和建议,并对PP/CNT复合材料的未来发展做出展望。     

混杂碳质填料对聚丙烯流变性能的影响

为研究多种碳质填料混杂对聚丙烯(PP)流变性能的影响,采用熔融共混法制备了聚丙烯(PP)/石墨烯(GNP)/碳纳米管(CNT)/炭黑(CB)复合材料,采用旋转流变仪研究了复合材料的流变行为。结果表明,加入的碳质填料,显著提高了复合材料的储能模量(G')、损耗模量(G″)以及复数黏度(η*)。在相同含量下,PP/CNT复合材料流变逾渗值最小,其次是PP/CB,最后是PP/GNP。当CNT含量超过0.5%时,PP/GNP/CNT复合材料出现了模量平台;当CB含量超过3%时,PP/GNP/CB复合材料出现模量平台;CNT与CB的协同作用最佳,CNT和CB的加入有利于GNP的分散;GNP与少量的CNT和CB共混能使G'、G″以及η*得到明显提高,同时,能够大幅减小流变逾渗值;纯PP以及PP/GNP复合材料的损耗因子随频率的增加而下降,PP/CNT、PP/CB、PP/GNP/CNT/CB复合材料损耗因子随频率增加呈先升高后下降的趋势。     

聚丙烯/BA原位聚合改性MMT纳米复合材料的微观结构

通过原位聚合制备了聚丙烯酸丁酯（PBA）改性蒙脱土（MMT），再与PP熔融复合，制成PP／MMT复合材料，利用X射线衍射（XRD）、扫描电子显微镜（SEM）和电子探直表征了复合材料的微观结构。结果表明：PP／MMT复合材料为纳米复合材料，MMT的加入诱导了β－晶型PP的形成。     

聚碳酸酯/碳纳米管纳米复合材料的研究进展

综述了聚碳酸酯(PC)／碳纳米管(CNT)纳米复合材料研究的最新进展。介绍了2种不同CNT的物理特性和PC／CNT纳米复合材料的制备方法以及CNT对PC／CNT纳米复合材料的力学性能、流变性能、电性能和结晶性能的影响。PC／CNT纳米复合材料是近年来CNT研究的新热点。     

聚丙烯／蒙脱土纳米复合材料研究进展

简要介绍了蒙脱＋（MMT）的结构、插层原理和表面修饰方法,并介绍了聚丙烯（PP）／MMT纳米复合材料的制备原理和方法。综述了PP／MMT纳米复合材料的国内外研究进展。     

PCL-g-MAH反应性增容对PP/EPDM/CNT复合材料性能与结构的影响

以聚丙烯(PP)/三元乙丙橡胶(EPDM)为基体,加入碳纳米管(CNT)制备了PP/EPDM/CNT复合材料。以马来酸酐接枝聚己内酯(PCL-g-MAH)为增容剂,对复合材料进行反应性增容。对反应性增容后的复合材料进行了表征,并分析了PCL-g-MAH对复合材料力学性能、加工流变性能、动态力学性能、熔体流动性能的影响。结果表明：PCL-g-MAH可以提高PP/EPDM基体与CNT的相容性,增强两者的界面黏结力,使CNT带来的力学增强效果更加显著,力学性能和熔体流动性更佳。     

碳化钨/碳纳米管纳米复合材料的制备及其对硝基苯的电催化活性

采用表面修饰技术和原位还原碳化技术制备了纳米碳化钨（WC）/碳纳米管（CNT）纳米复合材料,通过X射线衍射（XRD）、扫描电子显微镜（SEM）和热重-差热分析（TG-DTA）等手段对WC/CNT纳米复合材料的晶相组成、形态结构和热稳定性进行了表征,结果显示样品是由WC和CNT两相构成,纳米WC颗粒均匀地分散在碳纳米管上,粒径细小;在空气气氛中,WC/CNT纳米复合材料在470℃以下保持稳定。采用循环伏安法研究了WC/CNT纳米复合材料对硝基苯的电催化活性和电化学稳定性。结果表明,WC/CNT纳米复合材料对硝基苯的电催化活性优于纳米WC和CNT,且WC/CNT纳米复合材料在硝基苯电还原过程中保持良好的化学稳定性。     

纳米有机蒙脱土改性SEBS/PP共混物的研究

通过熔融插层的方法将纳米有机蒙脱土（OMMT）与氢化苯乙烯-丁二烯-苯乙烯嵌段共聚物（SEBS）／聚丙烯（PP）共混制备得到SEBS／PP／OMMT复合材料。X射线衍射实验证明,复合材料SEBS／PP／OMMT5％、SEBS／PP／OMMT10％片层间距分别为4．17nm,3．91nm,说明聚合物插层进入OMMT片层之间,制备得到SEBS／PP／OMMT插层复合材料。采用锥形量热仪测试材料的阻燃性能,燃烧测试结果表明,SEBS／PP／OMMT复合材料具有比较低的热释放速率和质量损失速率,并且随着OMMT添加量增加,复合材料的热释放速率、峰值热释放速率和总热释放先显著降低最后趋于一个稳定值。综合力学测试结果表明,当有机蒙脱土质量分数为5％～10％时,该复合材料的综合性能最好。     

PP／PPMA／Org—MMT复合材料的制备与性能研究

采用熔融插层法制备PP／PPMA／Org-MMT复合材料，考察接枝物含量、不同聚丙烯、不同接枝率接枝物以及不同成型工艺对PP／PPMA／Org-MMT复合材料的制备与力学性能的影响。结果表明，采用PP（F401）、高接枝率接枝物和模压工艺可获得较好的插层效果。接枝物含量为10％时，PP／PPMA／Org-MMT复合材料的拉伸强度达到最大值。     

Comparative study of EMI shielding effectiveness for carbon fiber pultruded polypropylene/poly(lactic acid)/multiwall CNT composites prepared by injection molding versus screw extrusion

The electrical conductivity and electromagnetic interference (EMI) shielding effectiveness of the composites of polypropylene/poly(lactic acid) (PP/PLA) (70/30, wt %) with single filler of multiwall carbon nanotube (CNT) or hybrid fillers of nickel‐coated carbon fiber (CF) and CNT were investigated. For the single filler composite, higher electrical conductivity was observed when the PP‐g‐maleic anhydride was added as a compatibilizer between the PP and PLA. For the composite of the PP/PLA (70/30)/CF (20 phr)/CNT (5 phr), the composite prepared by injection molding observed a higher EMI shielding effectiveness of 50.5 dB than the composite prepared by screw extrusion (32.3 dB), demonstrating an EMI shielding effectiveness increase of 49.8%. The higher values in EMI shielding effectiveness and electrical conductivity of the PP/PLA/CF (20 phr)/CNT (5 phr) composite seemed mainly because of the increased CF length when the composites were prepared using injection molding machine, compared with the composites prepared by screw extrusion. This result suggests that the fiber length of the conductive filler is an important factor in obtaining higher values of electrical conductivity and EMI shielding effectiveness of the PP/PLA/CF/CNT composites. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45222.     

Influence of ultrasonic treatment in PP/CNT composites using masterbatch dilution method

Composites of polypropylene (PP) filled with multiwalled carbon nanotubes (CNTs) of various concentrations were prepared by a twin screw extruder using direct compounding (DC) method without and with ultrasonic treatment. In addition, a masterbatch of 20 wt% PP/CNT composites were prepared without and with ultrasonic treatment and diluted to the same concentrations as in the DC method without ultrasonic treatment. This is called the masterbatch dilution (MD) method. The rheological, electrical and mechanical properties were investigated. The microdispersion was determined using optical microscopy to correlate the processing, properties and structure. It was shown that the MD method provided better dispersion of CNT in PP matrix than the DC method. This was indicated by an increase of the storage modulus, viscosity, electrical and mechanical properties. The fractal dimension of CNTs, D, and the backbone fractal dimension, x, of the CNT network were determined by fitting the rheological data to the scaling model. The lower fractal dimension of CNT and higher backbone fractal dimension of CNT network in composites prepared by the MD method compared with composites obtained by the DC method indicated a better dispersion. Additionally, a lower D and a higher x values as well as the favorable effect on the morphology and mechanical properties were achieved when the ultrasonic treatment at an amplitude of 13 μm was applied in the MD method, indicating an advantage in use of the ultrasonic treatment in preparing the PP/CNT masterbatch.     

碳纳米管增强纳米银复合材料应用进展

归纳了碳纳米管增强纳米银复合材料(Ag/CNT)的制备途径及性能变化,阐述了Ag/CNT复合材料在水离子体检测、抗菌、催化、传感器等领域的应用。并指出:在制备方式中,在吸附型CNT沉积纳米银(Ag/a–CNT)复合物质制备过程中,由于CNT表面基团的保护效应,致使纳米Ag在CNT表面均匀分散,同时,CNT大的比表面积又增强了银纳米粒子的吸附作用。Ag/a–CNT将是以后CNT增强纳米银复合材料主要的制备方式。另外,纳米银的加入不仅可以增强复合物质光学和热学性能,而且还能产生复合材料新的其它性能和应用。如何在保证复合材料应用效果的情况下,降低成本和实现工业化生产都将是今后的努力方向。     

Characterization of carbon nanotube- and organoclay-filled polypropylene/poly(butylene succinate) blend-based nanocomposites with enhanced rigidity and electrical conductivity

In this study, immiscible polypropylene/poly(butylene succinate) (PP/PBS) blend-based nanocomposites were successfully prepared using an internal mixer. Carbon nanotube (CNT)/organo-montmorillonite (15A) and maleated PP (PPgMA) served as the reinforcing nanofillers and compatibilizer, respectively. Scanning electron microscopy results showed that PPgMA played an efficient role as compatibilizer for reducing the dispersed domain size of PBS in the blend. The added CNT was randomly distributed within the PP and PBS phases, whereas 15A was selectively located in the PBS domain. Differential scanning calorimetry results confirmed the nucleation effect of CNT on the PP/PBS crystallization, but 15A addition only facilitated the PBS crystallization. Thermogravimetric analysis revealed that CNT and 15A both enhanced the thermal stability of the blend under air environment. The rheological property measurements confirmed the significant change in microstructure of composites through developing the pseudo-network structure with CNT and/or 15A additions. The Young’s modulus (YM) of PP/PBS blend increased evidently with the inclusion of CNT. The incorporation of 2.5 phr CNT evidently increased the YM by approximately 243% compared with that of neat PBS. The electrical resistivity of the samples drastically reduced with the addition of CNT up to 10 orders of drop at a 3-phr CNT loading. The electrical percolation was constructed at a CNT content of 0.5 phr.     

Ultrasonic treatment of PP/CNT composites during twin‐screw extrusion: Effect of screw configuration

PP/CNT composites were prepared by means of an ultrasonic twin extruder with three screw configurations at ultrasonic amplitudes up to 13 μm to compare their efficiency in dispersing CNT in PP. Using these screw configurations, the pressure in the ultrasonic treatment zone was varied in order to elucidate the effect of pressure on ultrasonic cavitation behavior in PP and PP/CNT composites. Rheological and mechanical behaviors were analyzed to reflect the dispersion of CNT. The results indicated that the dispersion of CNT in PP is more related to the number of kneading elements in the screw configuration and less to the residence time. This was explained by simulating the mixing effect using the flow analysis network. Comparison of the complex viscosities of untreated and treated PP indicated that at the same amplitude of ultrasonic treatment, PP degraded more at lower ambient pressure. At the lowest ambient pressure, the cavitation in the polymer matrix was intense at the highest amplitude but it had not always led to the best dispersion due to the suppression of the cavitation in the agglomerates. Therefore, the ultrasonic treatment increased the dispersion level of CNT in PP with the best improvement not always occurring at the highest amplitude. Composites prepared at an ultrasonic amplitude of 10 μm in the screw configuration providing an intermediate pressure exhibited elongation at break as high as 320% compared to 247% for the untreated composites. POLYM. COMPOS., 38:2695–2706, 2017. © 2015 Society of Plastics Engineers     

Polypropylene/poly(lactic acid)/carbon nanotube semi-biodegradable nanocomposites: The effect of sequential mixing approach and compatibilization on morphology,rheology and electrical conductivity

Semi-biodegradable polypropylene (PP)/poly(lactic acid) (PLA) (50:50 vol%) blend loaded with 0.6 vol% of pristine carbon nanotube (CNT) were prepared by melt compounding the components using different sequential mixing strategies: (i) all components together (PP/PLA/CNT); (ii) PP first mixed with CNT (PP@CNT/EVA) and (iii) EVA first mixed with CNT (EVA@CNT/PP). The composites presented co-continuous structure and the CNT selectively localized inside the PP phase or at the interface, regardless the order of the CNT addition into the mixing. These features were confirmed by selective extraction experiments and morphological studies: optical, scanning electron, and transmission electron microscopy. However, the preferential localization at the interface was predicted from wetting coefficient, determined from interfacial energy. Higher electrical conductivity values were achieved by using the one-step mixing approach, were all components were mixed together, whose value of around 10⁻⁴ S/m was achieved by adding 0.6 vol% of CNT to the blend. The compatibilization with polypropylene-g-maleic anhydride increased the melt viscosity of the blend and composite but did not affect the conductivity or the tensile properties of the CNT-based composite.     

Poly(propylene) composite with hybrid nanofiller: Dynamic properties

Mechanical, impact, and relaxation properties of in situ synthesized carbon nanotubes‐polyaniline (CNT‐PANi) hybrid nanoparticle‐filled poly(propylene) (PP) composites with or without an amphiphilic dispersing agent were investigated using tensile testing, notched Charpy impact testing, and dynamical mechanical testing methods. The reference material was MWCNT filled PP composite. Ethyl gallate (EG) was the dispersing agent which realizes high conductivity in PP composites with hybrid filler. Measured properties showed quite similar behavior of CNT‐PANi hybrid and neat CNT filled composites. Addition of 20% EG in PP did not cause essential differences compared to the neat PP. When the dispersing agent was added in filler containing PP composites, remarkable effects were observed, especially in PP‐hybrid composites. Mechanically, these materials had improved tensile properties, but they were brittle compared to the materials without dispersing agent. Dynamic mechanical analysis showed improvement in storage modulus, and in loss modulus the α transition was well observable. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Influence of Thrower–Stone–Wales defects on the interfacial properties of carbon nanotube/polypropylene composites by a molecular dynamics approach

A molecular dynamics (MD) simulations study is performed on Thrower–Stone–Wales (TSW) defected carbon nanotube (CNT)/polypropylene (PP) composites. We identify the degradation of the CNT and the improvement of the interfacial adhesion between the defected CNTs and PP molecules considering different CNTs with different numbers of TSW defects. By embedding the CNTs into a PP matrix, the effect of the TSW defects on the transversely isotropic elastic stiffness of polymer composites is calculated by MD simulations. Even if the TSW defects degrade the elastic properties of the CNTs, the transverse Young’s modulus and the transverse and longitudinal shear moduli of the composites increase due to the stronger interfacial adhesion between the defected CNTs and matrix, whereas the longitudinal Young’s modulus of the composites decreases. To elucidate the improved interfacial load transfer between the CNTs and the matrix, random polymer chain crystallization onto the surface of CNTs is simulated. The simulation shows that PP chains are wrapped more uniformly onto the surfaces of defected CNTs than onto the pristine CNT. The non-bond adhesion energy between the PP chains and the defected CNTs is greater than that between the PP chains and the pristine CNT.     

Effect of solid state grinding on properties of PP/PET blends and their composites with carbon nanotubes

In this study, it was aimed to improve electrical conductivity and mechanical properties of conductive polymer composites, composed of polypropylene (PP), poly(ethylene terephthalate) (PET), and carbon nanotubes (CNT). Grinding, a type of solid state processing technique, was applied to PP/PET and PP/PET/CNT systems to reduce average domain size of blend phases and to improve interfacial adhesion between these phases. Surface energy measurements showed that carbon nanotubes might be selectively localized at PET phase of immiscible blend systems. Grinding technique exhibited improvement in electrical conductivity and mechanical properties of PP/PET/CNT systems at low PET compositions. Ground composites molded below the melting temperature of PET exhibited higher tensile strength and modulus values than those prepared above the melting temperature of PET. According to SEM micrographs, micron‐sized domain structures were obtained with ground composite systems in which PET was the minor phase. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010