原位缩聚法制备碳纳米管/尼龙11复合材料

用原位缩聚法制备了碳纳米管增强的尼龙11复合材料,用X射线衍射仪、红外(FTIR)、扫描电镜(SEM)、热重(TGA)、机械拉伸测试仪等对其结构、形貌、热性能及机械性能进行了表征测试.扫描电镜结果显示碳纳米管均一地分散在尼龙11/碳纳米管复合材料中.复合材料的拉伸模量比纯尼龙11有较大的提高.当复合材料中碳纳米管含量分别为1%,5%,10%时,材料的拉伸模量分别提高了34.5%,92.9%和113,7%.同时,复合材料的储能模量也有提高.热分析结果显示当复合材料中碳纳米管含量为1%时,其失重5%和10%的温度分别由纯尼龙11的404℃、424℃提高到414℃和437℃.示差扫描量热分析(DSC)显示复合材料的结晶温度随碳纳米管的加入而升高,而结晶度则降低.

in situ POLYMERIZATION APPROACH TO MULTIWALLED CARBON NANOTUBES REINFORCED POLYUNDECANOYLAMIDE COMPOSITES

Multiwalled carbon nanotubes reinforced nylon 11 (PA11) composites were prepared by in situ polymerization of 11-(amino acid) in the presence of carboxylic acid-functionalized MWNTs (MWNT-COOH).The structure,morphology and mechanical properties were analyzed by X-ray diffraction patterning,FTIR spectroscopy,scanning electron microscopy (SEM),and mechanical tensile tests.The SEM imaging shows that MWNTs are uniformly dispersed in the PA11/MWNTs composites,which benefits to enhance the mechanical properties of the composites.The composites' tensile modulus is highly superior to that of pure PA11,and it's incremental quantity increases with the content of MWNTs.Increments of 34.5%,92.9%,and 113.7% were found for the composites containing 1%,5%,and 10% MWNTs,respectively.Moreover,the composites' storage modulus increases obviously with the content of MWNTs.Thermogravimetric analysis (TGA) shows the composites' initial thermal degradation temperature is enhanced when adding nanotubes in the polymer substrate.When the content of MWNTs reaches 1%,the composites' degradation temperature of losing weight 5% or 10% enhances from 404℃ to 414℃,or from 424℃ to 437℃.Differential scanning calorimetry (DSC) shows that the degree of crystallization of the nylon/MWNTs composites decreases as the content of nanotubes increases.