Glucose-functionalized multi-walled carbon nanotubes dispersing and hosting nanotubes for poly(amide-imide) bionanocomposites containing N,N′-(pyromellitoyl)-bis-S-valine

Hybrid bionanocomposites (BNCs) were produced via incorporating multi-walled carbon nanotubes (MWCNTs) into a biodegradable poly(amide-imide) (PAI) matrix. MWCN Ts were functionalized with glucose as a biologically active molecule in a green pathway to achieve a fine dispersion of MWCNT bundles in the polymer matrix. The optically active and biodegradable PAI was formed from the polycondensation reaction of N,N'-(pyromellitoyl)-bis-S-valine as an optically active diacid with 4,4'-methylene-bis(3-chloro-2,6-diethylaniline) as an aromatic diamine in a green condition. The polymer obtained and glucose-functionalized MWCNTs (f-MWCNTs) were used to prepare PAI/ f-MWCNT BNCs through ultrasonic irradiation. BNCs containing 5, 10, and 15 wt.% of f-MWCNTs exhibited a relatively good dispersion at the macroscopic scale. Field emission scanning and transmission electron microscopy micrographs of the composites showed that f-MWCNTs made a good interaction with polymer chains, and nanotubes wholly separated and uniformly dispersed in the polymer matrix. Adding f-MWCNTs into the polymer matrix significantly increased the thermal stability of the BNCs due to the increased interfacial interaction between the PAI matrix and the modified f-MWCNTs and their improved dispersion.