尼龙6/蒙脱土纳米复合材料的合成新方法

利用微波加热交换法分两步将浮选后的天然钠基蒙脱土转变为镍基蒙脱土,通过配位理论把单体引入镍基蒙脱土层间,制得尼龙6/蒙脱土纳米复合材料。为制备尼龙6/蒙脱土纳米复合材料提供了一种新方法。     

MC尼龙／蒙脱土纳米复合材料在榨糖机轴瓦的应用

介绍了采用在MC尼龙聚合过程中,添加适量的纳米蒙脱土,制备MC尼龙/蒙脱土纳米复合材料的方法.将MC尼龙/蒙脱土纳米复合材料与普通MC尼龙进行性能比较,测得其维卡温度、弯曲强度、硬度和耐磨性比普通MC尼龙都有明显提高;并在部分糖厂的压榨机上试用MC尼龙/蒙脱土纳米复合材料制备的轴瓦,试用结果显示:轴瓦磨损量少,没有"抱瓦"现象,可进一步推广.     

尼龙11/蒙脱土纳米复合材料形态和性能研究

通过熔融共混法成功地制备了不同含量蒙脱土的尼龙11/蒙脱土纳米复合材料,利用X衍射(XRD)和透射电镜(TEM)研究了尼龙11/蒙脱土纳米复合材料的微观结构。结果表明,当蒙脱土质量分数小于2%时,形成了剥离型的纳米复合材料,当蒙脱土质量分数超过2%时形成了插层型的纳米复合材料。热重分析表明当蒙脱土质量分数为2%时,纳米复合材料的热分解温度比纯尼龙11提高了27℃。不同蒙脱土含量的纳米复合材料悬臂梁冲击强度均比纯尼龙11的高,但其拉伸强度在蒙脱土质量分数小于8%时降低,以后随蒙脱土含量的增加而提高。     

尼龙11/蒙脱土纳米复合材料的研究

采用熔体插层法制备了尼龙11／蒙脱土纳米复合材料。研究了纳米蒙脱土对尼龙11力学性能的影响。结果表明,在蒙脱土含量为5％时,尼龙11／蒙脱土纳米复合材料的冲击强度达到最大值,是纯尼龙11冲击强度的2．5倍;随着蒙脱土含量的增加,复合材料的拉伸强度先降低后升高,但变化幅度不大。通过电镜观察冲击断面形态发现,蒙脱土以片状形式均匀分散在尼龙11基体中,受冲击时基体产生了屈服。     

尼龙6/蒙脱土纳米复合材料的研究及应用

综述了尼龙6／蒙脱土纳米复合材料的制备、结构、性能及应用，比较了插层聚合法和熔融共混法2种制备工艺，介绍了蒙脱土来源、尼龙品种对复合材料结构及性能的影响。     

尼龙6/纳米蒙脱土母料的水辅法制备及性能

依据水是蒙脱土的膨胀剂原理,通过实验研究水辅熔融法制备尼龙6/纳米蒙脱土母料的可行性,以及工艺条件、含量对纳米母料制备的影响.在此基础上,通过母料制备尼龙6/蒙脱土纳米复合材料,并对其力学性能与热变形温度进行测定.实验表明:通过水辅熔融法能够制备尼龙6/纳米蒙脱土母料;采用15%与30%蒙脱土含量的母料与尼龙6分别按1:4与1:9的比例稀释,两种稀释样品与纯尼龙6相比,拉伸强度分别提高了约24%与11%,弹性模量分别提高了49.8%与22.9%,弯曲强度分别提高了近66.6%与26%,弯曲模量分别提高了85%与16.7%,热变形温度明显提高.     

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,...     

尼龙/蒙脱土纳米复合材料研究进展

介绍了尼龙／蒙脱土纳米复合材料的制备方法，并对国内外关于尼龙／蒙脱土纳米复合材料热性能、力学性能、流变性能、结晶性能以及插层动力学研究进展进行了综述。结果认为，尼龙／蒙脱土纳米复合材料是一种新型的复合材料，蒙脱土的加入，改进了尼龙的力学性能，提高了复合材料的热变形温度。     

蒙脱土结构特性及在聚合物基纳米复合材料中的应用

对蒙脱土的晶层结构、分散性、流变性及表面修饰进行了系统的评述。蒙脱土片层含有Lewis酸点及过渡金属离子可用于烯类单体的催化聚合反应;自从丰田汽车公司使用尼龙 6／粘土纳米复合材料以来,蒙脱土(具有膨润性的粘土)在聚合物基纳米复合材料中的研究和应用正越来越受到世人的关注。对蒙脱土／聚合物纳米复合材料的制备方法及其进展也进行了综述。     

尼龙6-聚乙烯合金/蒙脱土纳米复合材料的制备与物理机械性能

用熔融插层法制备了尼龙6-聚乙烯合金/蒙脱土纳米复合材料.X射线衍射表明,在有机蒙脱土质量分数为4%,6%时,蒙脱土被剥离成片层分散在基体中;进一步提高蒙脱土质量分数至10%,蒙脱土部分剥离,部分插层.物理机械性能测试结果表明,将有机蒙脱土加入尼龙6-聚乙烯合金中能显著提高复合材料的拉伸强度、弯曲强度、冲击强度.其中冲击强度最大可以提高100%以上.     

Polymorphic behavior of nylon 6/saponite and nylon 6/montmorillonite nanocomposites

X‐ray diffraction methods and DSC thermal analysis have been used to investigate the structural change of nylon 6/clay nanocomposites. Nylon 6/clay has prepared by the intercalation of ε‐caprolactam and then exfoliaton of the layered saponite or montmorillonite by subsequent polymerization. Both X‐ray diffraction data and DSC results indicate the presence of polymorphism in nylon 6 and in nylon 6/clay nanocomposites. This polymorphic behavior is dependent on the cooling rate of nylon 6/clay nanocomposites from melt and the content of saponite or montmorillonite in nylon 6/clay nanocomposites. The quenching from the melt induces the crystallization into the γ crystalline form. The addition of clay increases the crystallization rate of the α crystalline form at lower saponite content and promotes the heterophase nucleation of γ crystalline form at higher saponite or montmorillonite content. The effect of thermal treatment on the crystalline structure of nylon 6/clay nanocomposites in the range between Tg and Tm is also discussed.     

Nylon 6/Na-montmorillonite nanocomposites prepared by compounding Nylon 6 with Na-montmorillonite slurry

We report a novel compounding process using Na-montmorillonite water slurry for preparing novel nylon 6/Na-montmorillonite nanocomposites. In this compounding process, the Na-montmorillonite slurry was blended with melting nylon 6 using an extruder, followed by removing the water. The Na-montmorillonite silicate layers were found to be exfoliated and dispersed homogeneously at nanometer level in the nanocomposites with an electron transmission microscope. The exfoliated Na-montmorillonite silicate layers were fixed in the nylon 6 matrix almost as they were in water. The nylon 6/Na-montmorillonite nanocomposites, loaded with only 1.6 wt% clay silicate layers, exhibited high strength, high modulus, high heat distortion temperature and low gas permeability compared to neat nylon 6. The properties of the nylon 6/Na-montmorillonite nanocomposites were nearly equal to those of conventional nylon 6/clay nanocomposites prepared by dry-compounding nylon 6 and organophilic clay ion-exchanged with alkylammonium ions.     

MC尼龙6/纳米ZnO复合材料的研究

采用硅烷偶联剂KH-550修饰纳米ZnO,制备了MC尼龙6/纳米ZnO复合材料。力学性能测试表明,当纳米ZnO质量分数为1%时复合材料的力学性能最优,拉伸强度比纯MC尼龙6提高25.6%,断裂伸长率提高165.6%,简支梁冲击强度提高70.1%,这说明纳米ZnO可起到同时增强增韧的作用。扫描电子显微镜分析表明,纳米ZnO质量分数为1%时,纳米ZnO在MC尼龙6基体中分散最好,达到了纳米级分散;由X衍射分析发现,纳米ZnO没有改变MC尼龙6的结晶形态,纳米ZnO质量分数为1%时复合材料的结晶形态结构优越。     

Fiber breakage and dispersion in carbon‐fiber‐reinforced nylon 6/clay nanocomposites

In this paper, short carbon‐fiber‐reinforced nylon 6/clay nanocomposites are prepared via melt compounding, and fiber breakage and dispersion during processing are studied. The influences of clay and processing conditions on fiber breakage and dispersion are taken into consideration. It is found that the presence of organoclay can improve fiber dispersion, which is due to dispersion at the nanoscale of exfoliated clay sheets with large aspect ratio. The bimodal distribution of fiber length is observed in fiber‐reinforced nanocomposites, which is similar to that in conventional fiber‐reinforced composites. The improvement of fiber breakage at moderate organoclay loadings is also observed, which is ascribed to the rheological and lubricating effects induced by organoclay. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007     

增强耐磨尼龙6材料的研制

研制了主要用于煤碳工业洗煤厂的脱水筛板的新型耐磨材料。尼龙6虽然具有良好的综合性能,但是用于洗煤厂的脱水筛板时,其力学性能和耐磨性均不能满足产品的使用要求,而且产品易翘曲变形。通过用玻璃纤维、耐磨填料等填充改性,使改性尼龙6的力学性能有较大的提高,摩擦系数仅为尼龙6的四分之一。将改性尼龙6材料制作筛板小样,经煤水混合物的冲刷磨损的模拟试验,其材料的综合性能均满足脱水筛板的使用要求.     

尼龙6/粘土纳米复合材料的性能

对尼龙6/粘土纳米复合材料(PA6CN)的力学性能、结晶性能、流变性能、热稳定性、阻隔性能、阻燃性能、各向异性和可纺性进行了综述。加入粘土后,基体尼龙6的晶型变为γ型,改善了尼龙6的力学性能,提高了热变形温度,降低了吸水率,改善了气体阻隔性和材料的阻燃性,拓宽了复合材料的应用范围。     

Isothermal crystallization kinetics and melting behavior of nylon/saponite and nylon/montmorillonite nanocomposites

DSC thermal analysis and X‐ray diffraction have been used to investigate the isothermal crystallization behavior and crystalline structure of nylon 6/clay nanocomposites. Nylon 6/clay has prepared by the intercalation of ε‐caprolactam and then exfoliating the layered silicates by subsequent polymerization. The DSC isothermal results reveal that introducing saponite into the nylon structure causes strongly heterogeneous nucleation induced change of the crystal growth process from a two‐dimensional crystal growth to a three dimensional spherulitic growth. But the crystal growth mechanism of nylon/montmorillonite nanocomposites is a mixed two‐dimensional and three‐dimensional spherulitic growth. The activation energy drastically decreases with the presence of 2.5 wt % clay in nylon/clay nanocomposites and then slightly increases with increasing clay content. The result indicates that the addition of clay into nylon induces the heterogeneous nucleation (a lower ΔE) at lower clay content and then reduces the transportation ability of polymer chains during crystallization processes at higher clay content (a higher ΔE). The correlation among crystallization kinetics, melting behavior, and crystalline structure of nylon/clay nanocomposites is also discussed. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 2196–2204, 2004     

Abrasion studies of nylon 6/montmorillonite nanocomposites using scanning electron microscopy,fourier transform infrared spectroscopy,and X‐ray photoelectron spectroscopy

In this article, abrasion performance of commercial nylon 6 and nylon 6/montmorillonite (MMT) nanocomposites was studied. The polymer nanocomposites showed poor abrasion resistance compared to the neat polymer. The wear loss increased linearly with clay concentration. Changes in surface morphology, composition, and structure were investigated by scanning electron microscopy (SEM), Fourier transform infrared (FTIR)‐attenuated total reflection spectroscopy, and X‐ray photoelectron spectroscopy (XPS). SEM images showed that all the abraded surfaces contained fractured particles. However, the abraded nanocomposite surfaces had much deeper grooves compared to the homopolymer. FTIR results showed an increase in the amount of α crystals and a decrease in the amount of γ crystals on all the surfaces after abrasion. This was attributed to the strain‐induced γ to α crystal transformation. The largest amount of α crystals was formed in the abraded surface of pure nylon 6, and the amount of α crystals formed decreased with increasing MMT content. XPS results showed an increase in the [Si]/[N] elemental ratio for all nanocomposites after abrasion, indicating an increase in the clay content of the surface. Abrasive wear mechanism is as follows: (1) tensile tearing is the dominant wear mechanism for all the samples; (2) the cutting mechanism becomes more important when MMT content increases; (3) the polymer matrix is easier to be removed than clay during the abrasion process; (4) in nylon 6/MMT systems, the poor abrasion resistance is attributed to defects at the clay‐polymer interface, resulting in greater wear of the polymer matrix. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Studies on nylon 6/clay nanocomposites by melt‐intercalation process

The preparation of nylon 6/clay nanocomposites by a melt‐intercalation process is proposed. X‐ray diffraction and DSC results show that the crystal structure and crystallization behaviors of the nanocomposites are different from those of nylon 6. Mechanical and thermal testing shows that the properties of the nanocomposites are superior to nylon 6 in terms of the heat‐distortion temperature, strength, and modulus without sacrificing their impact strength. This is due to the nanoscale effects and the strong interaction between the nylon 6 matrix and the clay interface, as revealed by X‐ray diffraction, transmission electron microscopy, and Molau testing. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 71: 1133–1138, 1999     

纳米二氧化硅／MC尼龙6原位复合材料非等温结晶动力学

通过阴离子开环聚合法制各纳米二氧化硅／MC尼龙6原位复合材料,采用差示扫描量热法研究MC尼龙6及其原位纳米复合材料非等温结品行为,并利用修正Avrami方程的Jeziomy和Liu的方法进一步处理原位纳米复合材料的非等温结晶动力学,结果表明在纳米二氧化硅／MC尼龙6原位复合材料中,纳米二氧化硅对基体MC尼龙6的结晶有一定的成核作用,并提高了其结品速率。