Syntheses and flame retarding properties of DOPO polymers, melamine polymers, and DOPO-melamine copolymers

摘要

The 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) polymers, melamine polymers, and DOPO-melamine copolymers have been successfully synthesized, and their flame retarding properties have also been investigated by blending with polypropylene (PP)/styrene-ethylene-butylene-styrene (SEBS) alloys. Experimental results establish that all of them are good polymeric flame retardants. No blooming or color stains occur when they are incorporated into PP/SEBS alloys. Among lab-made polymeric flame retardants, DOPO-melamine copolymers exhibit the best thermal stability and nonflammability. PP/SEBS alloys containing DOPO-melamine copolymers display comparable thermal resistance and flame retarding behavior (T_d = 290℃; char yield: 15.6%, LOI: 23, and flammability: UL-94 V0) as the alloys containing common commercial flame retardants (i.e., DOPO, melamine, and ammonium polyphosphate).