多壁碳纳米管/聚酰亚胺复合材料制备及其性能研究

聚酰亚胺的前聚体,聚酰胺酸,是通过4,4-二氨基二苯醚(ODA)与3,3,4,4二苯甲酮四羧酸二酐(BTDA)反应制备的.未改性的、酸改性和胺改性的多壁碳纳米管(MWCNT)被分别地单独加入到聚酰胺酸溶液中,并加热至300℃,从而制成聚酰亚胺/碳纳米管复合材料.扫描型电子显微镜(SEM)和透射电子显微镜(TEM)的显微...

Preparation and properties of multi walled carbon nanotubes/polyimide composites

The precursor of polyimide,polyamic acid,was prepared by the reaction of 4,4-diaminodiphenyl ether(ODA)with 3,3,4,4-benzophenone tetracarboxylic dianhydride(BTDA).Unmodified,acid modified and amine modified multi walled carbon nanotubes(MWCNTs)were separately added to polyamic acid solution and heated to 300℃to prepare polyimide/carbon nanotube composites.Scanning electron microscopy(SEM)and transmission electron microscopy(TEM)micrographs showed that acid modified MWNTs and amine modified MWNTs were uniformly dispersed in the polyimide matrix.The effects of MWCNTs modified by acid and amine on the surface and volume resistivity of MWCNTs/polyimide composites were studied.It was found that the surface resistivity(ITES)of the nanocomposites decreased from 1.28×10¹⁵Ω/cm²(pure polyimide)to 7.59×10⁶Ω/cm²(26.98%of unmodified MWNTs).In addition,the addition of MWNTs affected the glass transition temperature of the nanocomposites.The significance of modified MWNTs was to improve the mechanical properties of nanocomposites.The tensile strength of MWCNTs/polyimide composites increased from 10²MPa(pure polyimide)to 134 MPa(6.98%acid modified MWCNTs/polyimide composites).