Study On The Preparation And Application Of A Novel Cyclic Phosphate Flame Retardant

According to information,many fires are caused by the burning of textiles.Treating textile flame retardant is an effective method to reduce fire,and preparing green and efficient flame retardant is the research hotspot of textile flame retardant.In this paper,three cyclic phosphate ester flame retardants and one expanded N-P flame retardant were prepared,and their synthesis process and application properties were studied in detail,and the following results were obtained:(1)Oxidized dicyclic diphosphite flame retardant(FR-1)was prepared from trimethylphosphine oxide(THPO)and triethyl phosphite(TEP)as raw materials under the action of self-made catalyst 1.The optimal synthesis process was as follows: THPO and TEP reacted with 2 % catalyst at 85 °Cat a molar ratio of 1:1.3 for 6 hours,and the fr-1 yield was97 %.The polyester fiber was treated with self-made flame-retardant FR-1,the amount of which was 150 g/L,the length of damaged carbon was 3cm,the smould-burning and reburning conditions disappeared,no droplet was found,the limit oxygen index(LOI)was40.5 %,and the flame-retardant performance reached national standard V-0 grade.(2)Cyclic phosphate ester flame retardant(FR-2)was prepared from self-made flame retardant FR-1 and DMMP under the action of self-made catalyst 2.The optimum synthesis process was as follows: the yield of FR-2 was 85 % when FR-1 reacted with DMMP at 1:1.05 molar ratio for 11 h at 160 °C using 3 % catalyst.Fr-2 was used for flame-retardant finishing of polyester fibers,the consumption was 150 g/L,the length of damaged carbon was 3.5 cm,the smould-burning and reburning conditions disappeared,there was no droplet,LOI was35.5 %,and the flame-retardant performance reached national standard V-0 grade.(3)Using THPO and DMMP as raw materials,the cyclic phosphate ester flame retardant(FR-3)was prepared by one-step method under the action of self-made catalyst 1.The optimum synthesis process was as follows: the fr-3 yield was 97.8 % at 140 °C when THPO reacted with DMMP for 7 h at a molar ratio of 1:1.1 using 3 % catalyst.Fr-3 was used to finish the polyester fiber with flame retardant,the consumption was 150 g/L,the length of damaged carbon was 2 cm,smoulderation and afterburning disappeared,no droplet was found,LOI was 40.5 %,and the flame retardant property of the polyester fiber reached national standard V-0 grade.In addition,flame-retardant finishing was also carried out on cotton cloth.When the dosage was 500 g/L and the dosage of crosslinking agent was 6 g/L,the damaged carbon length of the sample was 2.6 cm,smoulding and reburning disappeared,no droplet was found,and LOI was 35 %,which showed good flame-retardant effect(4)N–P dicyclic phosphite expansion flame retardant(FR-4)was prepared from triethanolamine(TEOA)and TEP under the action of self-made catalyst 1.The optimal synthesis process was as follows: the fr-4 yield was 95.01 % when TEOA reacted with TEP at1:1.2 molar ratio for 8h at 100 °C using 3 % catalyst.Fr-4 was used for flame-retardant finishing of dacron.When the consumption was 300 g/L,the length of damaged carbon was 3cm,smoulded and continued burning disappeared,no droplet was found,LOI was 35.5 %,and the flame-retardant performance reached national standard V-0 grade.