초록 ▼

A flame-retardant polypropylene composition comprises a modified polypropylene-based polymer, antimony oxide or sodium antimonate, and a halogenated organic compound or, in lieu thereof, a phosphorous-containing compound. The polypropylene-based polymer is modified in the presence of a free-radical

A flame-retardant polypropylene composition comprises a modified polypropylene-based polymer, antimony oxide or sodium antimonate, and a halogenated organic compound or, in lieu thereof, a phosphorous-containing compound. The polypropylene-based polymer is modified in the presence of a free-radical generator source which typically is an organic peroxide so that it has a narrow polydispersity range, improved flow, and lower compounding and molding temperatures so that temperature-sensitive components are protected from thermal degradation. The modification of the polypropylene-based polymer generally occurs in situ in the processing apparatus and the composition can also contain various fillers, fibers, and the like.

대표청구항 ▼

A flame-retardant polypropylene composition, comprising a blend of: about 100 parts by weight of a polypropylene-based polymer, said polypropylene-based polymer being 1) a polypropylene homopolymer, 2) a copolymer of propylene and ethylene, 3) a blend of said polypropylene homopolymer and said propy

A flame-retardant polypropylene composition, comprising a blend of: about 100 parts by weight of a polypropylene-based polymer, said polypropylene-based polymer being 1) a polypropylene homopolymer, 2) a copolymer of propylene and ethylene, 3) a blend of said polypropylene homopolymer and said propylene-ethylene copolymer, 4) a blend of said polypropylene homopolymer, said propylene-ethylene copolymer, or said blend of said polypropylene homopolymer and said propylene-ethylene copolymer with (a) an EPDM copolymer and/or (b) a block copolymer containing at least one A block and at least one B block wherein said A block is made from a vinyl substituted aromatic monomer having from 8 to 15 carbon atoms and wherein said B block is made from a conjugated diene monomer having from 4 to 10 carbon atoms, 5) a blend of said polypropylene homopolymer, said propylene-ethylene copolymer, or said blend of said polypropylene homopolymer and said propylene-ethylene copolymer with (c) a polyethylene and/or (d) a copolymer of ethylene and a vinyl ester, wherein said ester portion has from 2 to 6 carbon atoms, or an acrylate wherein said ester portion of said acrylate has from 2 to 10 carbon atoms, or a blend of said 4) and said 5), an effective amount of an antimony component containing antimony oxide, sodium antimonate, or combinations thereof, to improve flame retardancy, said polypropylene-based polymer modified by chain scission in the presence of from about 0.01 to about 5.0 parts by weight per 100 parts by weight of said polypropylene-based polymer of a chemical free radical generator source, said antimony component, and a halogen organic compound, said modified polypropylene-based polymer having reduced polydispersity, a higher ASTM D1238 melt flow index, and processible at a temperature of at least 20°F. lower, in comparison with said unmodified polypropylene-based polymer, of said halogenated organic compound to improve flame retardancy, said halogen-containing compound being brominated dipentaerythritol, tetrabromobisphenol A, ethylene-bistetrabromophthalimide, ethylene bis dibromo norbornane-dicarboximide, tetrabromobisphenol A-bis(2,3-dibromo-propyl ether), octabromodiphenyl oxide, hexabromocyclododecane, hexabromodiphenoxy ethane, decabromodiphenoxy ethane, decabromodiphenyl oxide, tetradecabromodiphenoxy benzene, brominated polystyrene, poly-dibromophenyleneoxide, phenoxy terminated bisphenol A carbonate oligomers containing from about 50 to about 60 percent bromine, brominated epoxy resins containing from about 30 to about 60 percent bromine, or combinations thereof.