Nylon 610/functionalized multiwalled carbon nanotube composite prepared from in-situ interfacial polymerization

Pristine multiwalled carbon nanotubes (P-MWNTs) were functionalized. with 4-chlorobenzoic acid via "direct" Friedel-Crafts acylation in polyphosphoric acid (PPA)/phosphorous pentoxide (P2O5) medium. The resultant 4-chlorobenzoyl-functionalized MWNTs (F-MWNTs) were soluble in chlorinated solvents such as dichloromethane, chloroform, and carbon tetrachloride. A large scale of nylon 610/F-MWNT composite could be conveniently prepared by in situ interfacial polymerization of 1, 6-hexamethylenediamine (HMDA) in an aqueous phase, and sebacoyl chloride with F-MWNTs in an organic phase. Similarly, nylon 610/P-MWNT composite was also prepared for comparison. The state of F-MWNTs dispersion in nylon 610 matrix was distinctively better than that of P-MWNTs, which could be clearly discerned by both naked eye and scanning electron microcopy (SEM). As a result, the tensile strength of nylon 610/F-MWNT composite was 4.9-fold higher than that of nylon 610/P-MWNT composite. (C) 2008 Wiley Periodicals, Inc.