Abstract

Effect of organoclays on formation of intercalated/exfoliated structure in epoxy–clay nanocomposites at 2 wt% filler loading was carried by spectral analysis. Organoclays were dispersed in epoxy matrix by ultrasonication method. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA) were carried to characterize function group, morphology of structure, surface and glass transition temperature of the nanocomposite, respectively. FTIR study reveals the presence of epoxy in the galleries of organoclays was confirmed and proves the existence of chemical bonds between the organoclays and the epoxy matrix. XRD analysis indicated that, the interlayer spacing between the clay platelets was increased significantly, thus, the polymer is able to intercalate between the clay layers. As a result, the fully exfoliated structure was found in the E + NC-III nanocomposite while the intercalated structure was obtained in the E + NC-I, E + NC-II, E + NC-IV and E + NC-V nanocomposites. The glass transition temperature measured by TGA was increased with the addition of organoclay in epoxy matrix but decreased for unmodified nanoclay and neat composite. SEM imaging showed good filler dispersion and distribution in E + NC-III nanocomposite, highlighting the very smooth surface due to absence of clay aggregates and no voids.

摘要

通过光谱分析研究了有机粘土对填充 2 wt% 填料的环氧树脂-粘土纳米复合材料中插入/剥离结构形成的影响。通过超声法将有机粘土分散在环氧树脂基体中。通过傅里叶变换红外光谱(FTIR)、X射线衍射(XRD)、扫描电子显微镜(SEM)和热重分析(TGA)分别对纳米复合材料的官能团、结构形貌、表面和玻璃化转变温度进行表征。FTIR 研究揭示了有机粘土中环氧树脂的存在，并证明了有机粘土和环氧树脂基质之间存在化学键。XRD 分析表明，粘土片层之间的层间距显着增加，因此，聚合物能够嵌入粘土层之间。结果，在 E + NC-III 纳米复合材料中发现了完全剥离的结构，而在 E + NC-I、E + NC-II、E + NC-IV 和 E + NC-V 纳米复合材料中获得了插层结构. TGA 测量的玻璃化转变温度随着在环氧树脂基体中添加有机粘土而升高，但对于未改性的纳米粘土和纯复合材料则降低。SEM 成像显示 E+NC-III 纳米复合材料中填料的分散性和分布良好，由于没有粘土聚集体和空隙，突出了非常光滑的表面。TGA 测量的玻璃化转变温度随着在环氧树脂基体中添加有机粘土而升高，但对于未改性的纳米粘土和纯复合材料则降低。SEM 成像显示 E+NC-III 纳米复合材料中填料的分散性和分布良好，由于没有粘土聚集体和空隙，突出了非常光滑的表面。TGA 测量的玻璃化转变温度随着在环氧树脂基体中添加有机粘土而升高，但对于未改性的纳米粘土和纯复合材料则降低。SEM 成像显示 E+NC-III 纳米复合材料中填料的分散性和分布良好，由于没有粘土聚集体和空隙，突出了非常光滑的表面。