Preparation and Application Study of Nano-Sized Organic Bentonite Used for Composite Flame Retardant

Nono-sized organic bentonite (OMMT) was synthesized through intercalation modification process with organic phosphorus flame retardant (Cyagard RF-1) and quaternary ammonium salt (CTAB). Composite materials of polybutylene terephthalate (PBT)/OMMT, Polyamide-6 (PA6)/OMMT was prepared by a double screw extrusion. The flame retardancy and mechanical properties of these materials were characterized. Nano-sized OMMT has large interlayer spacings and good dispersion after modification. In compared with PBT and PA6, composite materials of PBT/OMMT and PA6/OMMT had high tensile strength, bending strength and notched impact strength, while their elongation decreased after addition of nano-sized OMMT, the limiting oxygen index ( LOI ) and UL94 vertical combustion of OBT/OMMT and PA6/OMMT composite materials with dosage of 3 wt% OMMT decreased slightly, in comparison with these composite metarials containing constant amounts of flame retardant.