Fire retardant composition and application thereof
The invention discloses a fire retardant composition and its application. The fire retardant composition is composed of the following ingredients, by weight, 55-90% of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 8-40% of pentaerythrityl phosphate and 0.5-10% of magnesium oxide. The composition can be applied in preparation of halogen-free fire-retardant ethylene propylene terpolymer. The fire retardant provided by the invention has advantages of small filling number, large oxygen index, high vertical burning level and low smoke density. The fire retardant can be used to prepare a low-hardness halogen-free fire-retardant ethylene propylene rubber material with hardness being less than 50 degrees. Meanwhile, as the fire retardant is a white powder and contains no carbon black or red phosphorus, etc., the fire retardant is convenient for preparation of colored fire-retardant rubber. 1. A kind of flame retardant composition, characterized in that the percentages by weight, the following components: 9, 10-dihydro-9-oxa -10-phosphaphenanthryl -10-oxide: 55-90% ; Pentaerythritol phosphate ester: 8-40%; Magnesium oxide: 0.5-10%. 2. The flame retardant composition according to Claim 1, characterized in that the weight percentage of each component: 9, 10-dihydro-9-oxa -10-phosphaphenanthryl -10-oxide: 70-75%; Pentaerythritol phosphate ester: 20-28%; Magnesium oxide: 1-5%. 3. A process for the preparation of flame retardant composition according to Claim 1, characterized in that comprises the following steps: the 9, 10-dihydro-9-oxa -10-phosphaphenanthryl -10-oxide, pentaerythritol phosphate into the high-speed mixing machine and the magnesium oxide, in the 70 under [...] , in order to 80 the rotational speed of the rotation/minute mixed 15-20min. 4. One or 2 is shown the application of the flame retardant composition according to Claim 1, characterized in that the flame-retardant composition is applied to the preparation of ethylene-propylene rubber. 5. The application of the fire retardant composition according to Claim 4, characterized in that the ethylene-propylene rubber preparation method comprises the following steps: A) adjusting the temperature of the rubber roll mill 30-60 the between [...] , the ethylene-propylene rubber matrix in turn, opens the processing additive mixed uniformly in the input; B) machine is to roll spacing of 0.5-1.5 mm, adding flame retardant composition, glue smashed, mixing 5-15min; C) the adjustment of the nip line spacing of mill 3-5mm, to continue mixing, until the to form a smooth non-gap sizing; D) step c) sizing the rolling piece, to be the film after the natural cooling at room temperature, into the mill machine again, by adding curing agent and an accelerator, the the 178-182 [...] , 14-16MPa vulcanization under the condition of 10 min, to obtain the flame retardant ethylene-propylene rubber. 6. The application of the fire retardant composition according to Claim 5, characterized in that the processing aid include zinc oxide, stearic acid, carbon black and paraffin oil, said accelerator including 2-thiol benzodioxanes thiazole and dimethyl sodium dithiaamino formate in one kind or two kinds of.