中文摘要：

通过尿素对高岭石的插层及随后的超声脱除处理,制备了一种片层剥离的高岭石粉体,并将这种剥离高岭石与聚氧化乙烯/高氯酸锂（PEO/LiClO4）体系复合,制备出PEO/高岭石复合物.采用X射线衍射仪、红外光谱仪、扫描电子显微镜、透射电子显微镜、扫描量热仪、电化学工作站和万能材料试验机进行结构表征和性能测试.结果表明,尿素在高岭石层间的插层和脱除引起了高岭石片层的剥离,片层厚度小于50 nm.剥离高岭石在PEO/LiClO4体系中与PEO形成了强烈的氢键作用,促进了PEO结晶度的降低,进而提高复合物的离子电导率.含有20 wt%剥离高岭石填料的PEO/高岭石复合物的离子电导率达到6.0×10^-5 S/cm,与未复合的PEO/LiClO4相比,提高了一个数量级.复合物制备过程中的烘干温度对PEO的结晶度会产生一定的影响,95℃下的烘干处理能得到结晶度较低,离子电导率较高的复合物.此外,剥离高岭石的添加显著提高了聚合物的杨氏模量和拉伸强度,与未复合的PEO/LiClO4相比,杨氏模量和拉伸强度最大提高了256%和121%.

英文摘要：

Kaolinite-urea intercalation complex was prepared using kaolinite as intercalation host and urea as intercalating agent. The kaolinite-urea intercalation complex was used as precursor to prepare exfoliated kaolinite by deintercalating urea molecules from the interlayers of kaolinite through ultrasonic treatment. X-ray diffraction（XRD） and scanning electron microscopy（SEM） were used to characterize the as-prepared exfoliated kaolinite. A broad 001 diffraction of kaolinite with weak intensity showed the random orientation of kaolinite platelets. SEM micrograph confirmed the exfoliation of kaolinite particles with layer thickness of no more than 50 nm. The exfoliated kaolinite particles were used as filler to poly（ethylene-oxide）/LiClO4（PEO/LiClO4） system to prepare PEO/kaolinite composites, with the aim to improve the ion conductivity and mechanical property of the PEO matrix. SEM, transmission electron microscopy（TEM）, XRD and Fourier transform infrared spectroscopy（FTIR） were used to characterize the PEO/kaolinite composites. SEM and TEM micrographs exhibited a good dispersion of exfoliated kaolinite in PEO matrix. XRD results showed that the crystallinity of PEO was gradually decreasing with increased exfoliated kaolinite content. FTIR analysis indicated that the hydrogen bonding was formed between the oxygen atoms of PEO segments and the hydroxyl groups on kaolinite surface, and this interaction between PEO and kaolinite was beneficial to the decrease in crystallinity of PEO. In order to evaluate the effect of the exfoliated kaolinite on ion conductivity and mechanical property of PEO matrix, AC impedance measurement and mechanical test were carried out. The results indicated that the ion conductivity of the composites gradually increased with increased exfoliated kaolinite content and reached 6.0 × 10^-5 S/cm at filler concentration of 20 wt%. The formation of amorphous region around the exfoliated kaolinite was beneficial for the Li^＋ ion conduction in PEO matrix. When the exfoliate