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.