Highly conductive thin films with suitable mechanical performances play a significant role in modern electronic industry. Herein, a series of ternary conductive polymer composites were fabricated by incorporating carbon black (CB) into binary conductive polymer composites of poly(amide-imide) (PAI) and polyaniline (PANI) to enhance their mechanical and conductive properties simultaneously. By varying the composition of PAI/PANI/CB ternary films, the conductivity enhanced by two orders of magnitude compared with the sum of PAI/PANI and PAI/CB binary conductive polymer composites, and a high conductivity of 1160 S m−1 was achieved. The improved conductivity is mainly because much more continuous conductive networks were constructed in the ternary conductive polymer composites. With the help of the unusual morphology, the tensile strength was also enhanced by more than 80% from 21 to 38 MPa. The origin for the improved morphology was discussed for further improvement.

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A series of novel ternary conductive composites have been prepared by incorporating functionalized multiwalled carbon nanotubes (FMWCNTs) into the binary composites of poly(amide-imide) (PAI) and poly( o-methoxyaniline) (POMA) to further improve the conductivity of PAI composites. With increasing the weight ratio of FMWCNTs, the conductivity of PAI/POMA/FMWCNTs ternary composites has been significantly enhanced from 10−3 S m−1 to 90 S m−1, much higher than that of the sum of PAI/POMA and PAI/FMWCNTs binary composites. The enhanced conductivity is mainly ascribed from a much more intensive conductive network formed in the PAI/POMA/FMWCNTs ternary composites. It is found that the N–H bending of amide group in the Fourier transform infrared spectrometry spectra is observed at 3298 cm−1 for PAI, 3296 cm−1 for PAI/POMA binary composites, and further blue shifted to 3292 cm−1 for PAI/POMA/FMWCNTs ternary composites. Moreover, the glass transition temperature has been increased from 82.5°C to 117.7°C. These results suggested that the hydrogen bonding interaction has been strengthened among PAI, POMA, and FMWCNTs, which is useful for dispersion of condcutive fillers into the polymer matrix.

Adaptive learning system must support different learning objectives and contexts of different learners. However only a very limited requirements above can be considered in present adaptive learning systems, especially in learning objectives. By extending the domain model and the user model and introducing the directed hypergragh theory in learning system, three types of adaptiveness to the user model: learning objective adaptiveness, learning navigation adaptiveness and learning content adaptiveness in learning system are defined formally, analyzed in detail, and implemented arithmetically. The research shows that three types of adaptiveness to the user model in learning system above can support the adaptiveness to different leaning objectives and styles of users effectively.

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