A pyrophosphate-free mixture with fire retardancy, including a mixture of non-polymer organic components, wherein at least a first compound of the mixture acts as a hydrogen-bridge donor and at least a second compound of the mixture acts as a hydrogen-bridge acceptor. The disclosure also relates to a method for preparing the fire-retardant mixture and to the use thereof as a fire retardant in extinguishing forest fires.

A trimerization catalyst composition suitable for making a polyisocyanurate comprising (insulation) foam, said composition comprising at least a trimerization catalyst compound selected from one or more organic salts from alkoxides wherein said organic salt is selected from alkali metal, earth alkali metal, a transition metal such as Ti and/or quaternary ammonium organic salts.

A trimerization catalyst composition suitable for making a polyisocyanurate comprising (insulation) foam, said composition comprising at least a trimerization catalyst compound selected from one or more organic salts from alkoxides wherein said organic salt is selected from alkali metal, earth alkali metal, a transition metal such as Ti and/or quaternary ammonium organic salts.

Disclosed is a flame retardant composition including: (A) 20 to 50 parts by mass of at least one melamine salt selected from the group consisting of melamine orthophosphate, melamine pyrophosphate, and melamine polyphosphate; (B) 50 to 80 parts by mass of at least one piperazine salt selected from the group consisting of piperazine orthophosphate, piperazine pyrophosphate, and piperazine polyphosphate (with the proviso that the total of component (A) and component (B) is 100 parts by mass); (C) 0.01 to 5.0 parts by mass of a silane coupling agent; and (D) 0.01 to 1.0 part by mass of an aliphatic dicarboxylic acid ether ester compound represented by general formula (1). The details of general formula (1) are as described in Description.

Disclosed is a flame retardant composition including: (A) 20 to 50 parts by mass of at least one melamine salt selected from the group consisting of melamine orthophosphate, melamine pyrophosphate, and melamine polyphosphate; (B) 50 to 80 parts by mass of at least one piperazine salt selected from the group consisting of piperazine orthophosphate, piperazine pyrophosphate, and piperazine polyphosphate (with the proviso that the total of component (A) and component (B) is 100 parts by mass); (C) 0.01 to 5.0 parts by mass of a silane coupling agent; and (D) 0.01 to 1.0 part by mass of an aliphatic dicarboxylic acid ether ester compound represented by general formula (1). The details of general formula (1) are as described in Description.

The present invention relates to a phosphazene compound containing an ester group having a structure of formula (I). The present invention grafts ester groups to phosphazene compounds and makes terminal grafted hydroxyl and carboxyl groups reacted with polymer matrix, producing an improvement of flame retardancy and a reduction of dielectric constant at the same time when the phosphazene compound is introduced into polymer matrix. Since N and P atoms are directly bonded into the polymer matrix by a reaction rather than addition and combination means in the prior art, there is no reduced mechanical properties of the matrix due to the addition of flame retardants.

The present invention relates to a phosphazene compound containing an ester group having a structure of formula (I). The present invention grafts ester groups to phosphazene compounds and makes terminal grafted hydroxyl and carboxyl groups reacted with polymer matrix, producing an improvement of flame retardancy and a reduction of dielectric constant at the same time when the phosphazene compound is introduced into polymer matrix. Since N and P atoms are directly bonded into the polymer matrix by a reaction rather than addition and combination means in the prior art, there is no reduced mechanical properties of the matrix due to the addition of flame retardants.

The invention relates to a mixture of at least one dialkylphosphinic acid of the formula (I)

##STR00001##

in which R.sup.1, R.sup.2 are the same or different and are each C.sub.1-C.sub.18-alkyl, C.sub.2-C.sub.18-alkenyl, C.sub.6-C.sub.18-aryl, C.sub.7-C.sub.18-alkylaryl, with at least one different dialkylphosphinic acid of the formula (II)

##STR00002##

in which R.sup.3, R.sup.4 are the same or different and are each C.sub.1-C.sub.18-alkyl, C.sub.2-C.sub.18-alkenyl, C.sub.6-C.sub.18-aryl and/or C.sub.7-C.sub.18-alkylaryl, with the proviso that at least one of the R.sup.3 and R.sup.4 radicals is different than R.sup.1 and R.sup.2.

The invention relates to a mixture of at least one dialkylphosphinic acid of the formula (I)

##STR00001##

in which R.sup.1, R.sup.2 are the same or different and are each C.sub.1-C.sub.18-alkyl, C.sub.2-C.sub.18-alkenyl, C.sub.6-C.sub.18-aryl, C.sub.7-C.sub.18-alkylaryl, with at least one different dialkylphosphinic acid of the formula (II)

##STR00002##

in which R.sup.3, R.sup.4 are the same or different and are each C.sub.1-C.sub.18-alkyl, C.sub.2-C.sub.18-alkenyl, C.sub.6-C.sub.18-aryl and/or C.sub.7-C.sub.18-alkylaryl, with the proviso that at least one of the R.sup.3 and R.sup.4 radicals is different than R.sup.1 and R.sup.2.

The present invention provides a flame-retardant engineering plastic and a preparation method thereof. The flame-retardant engineering plastic contains a halogen-free flame retardant represented by the formula I as a component of raw materials. The addition of the flame retardant gives good flame retardancy and excellent mechanical properties to the engineered plastic. The engineering plastic is prepared by the raw materials comprising the following components in parts by mass: 40-60 parts of PC, 20-40 parts of epoxy resin, 10-20 parts of ABS and 5-15 parts of flame retardant. The engineering plastic prepared by the present invention has a bending strength which can be up to 82.4-84 MPa, a tensile strength of up to 65.7-66.6 MPa, a notched impact strength of up to 26.3-27 J/m, a melt index of 12.6-15, and an oxygen index of 26.2-27.5%, and thus has excellent mechanical properties and good flame retardancy.