A composition comprises at least one condensed phosphorus compound. The condensed phosphorus compound is produced by reacting together in a condensation reaction a nitrogen compound and a phosphonium compound. A phosphorus-containing polymer is produced by reacting in a condensation reaction a hydroxyalkylphosphonium compound to produce an intermediate polymer and then oxidizing phosphorus atoms in the intermediate polymer to yield a polymer comprising phosphine oxide groups.

A composition comprises at least one condensed phosphorus compound. The condensed phosphorus compound is produced by reacting together in a condensation reaction a nitrogen compound and a phosphonium compound. A phosphorus-containing polymer is produced by reacting in a condensation reaction a hydroxyalkylphosphonium compound to produce an intermediate polymer and then oxidizing phosphorus atoms in the intermediate polymer to yield a polymer comprising phosphine oxide groups.

The present invention provides a siloxane-modified cyclotriphosphazene halogen-free flame retardant, and a preparation method and a use thereof. The siloxane-modified cyclotriphosphazene halogen-free flame retardant has the structural formula as shown in Formula I. In the siloxane-modified cyclotriphosphazene halogen-free flame retardant of the present invention, three kinds of structures of siloxane, aryl phosphorus oxygen compound and cyclotriphosphazene are built in one molecular formula, which combines the advantages of three structures, improves the compatibility between the flame retardant and resins, has a high flame retardant efficiency and a better char formation and can greatly increase the flame retardancy and stability of resin cured products.

Provided herein are formaldehyde-free flame retardant compositions, comprising a flame retardant acid and a fixing agent; and methods of their use for manufacturing durable formaldehyde-free flame retardant cellulosic materials. Also provided herein are durable formaldehyde-free flame retardant cellulosic materials and articles comprising the same.

Provided herein are formaldehyde-free flame retardant compositions, comprising a flame retardant acid and a fixing agent; and methods of their use for manufacturing durable formaldehyde-free flame retardant cellulosic materials. Also provided herein are durable formaldehyde-free flame retardant cellulosic materials and articles comprising the same.

The instant invention relates to a composition useful as a precursor for imparting flame-retardant properties to textile articles, comprising a condensate of: (a) a tetrakis (hydroxyorgano) phosphonium sulfate THPS; (b) urea, or alternatively thiourea; (c) optionally, and preferably, an aliphatic hydroxyl-reactive compound, such an amine wherein said composition has a very low free formaldehyde content, namely of less than 0.1%.

The instant invention relates to a composition useful as a precursor for imparting flame-retardant properties to textile articles, comprising a condensate of: (a) a tetrakis (hydroxyorgano) phosphonium sulfate THPS; (b) urea, or alternatively thiourea; (c) optionally, and preferably, an aliphatic hydroxyl-reactive compound, such an amine wherein said composition has a very low free formaldehyde content, namely of less than 0.1%.