Fire‐retardant copolymer of acrylonitrile with O,O‐diethyl‐O‐allyl thiophosphate

Abstract

A novel halogen-free flame retardant, O,Odiethyl-O-allyl thiophosphate (DATP), which simultaneously contained phosphorus and sulfur, was synthesized through a simple method. The structure of DATP was characterized by Fourier transform infrared spectroscopy, 1 H-NMR, and mass spectroscopy. The flame-retardant copolymer was obtained by the free-radical copolymerization of DATP with acrylonitrile. The flammability and thermal degradation characteristics of the copolymer were assayed by limiting oxygen index measurement, thermogravimetric analysis, and differential scanning calorimetry. The results show that the incorporation of a small percentage of DATP into the copolymer had a significant effect on the retarding combustion of the copolymer, with the limiting oxygen index of the copolymer reaching 28.5% and the char yield being 68.63 wt % at 554 C.

Flame‐retardant polyacrylonitrile fabric prepared by ultraviolet‐induced grafting with glycidyl methacrylate followed by ammoniation and phosphorylation

“…After phosphorylation, new absorption bands at 1160 cm −1 and 938 cm −1 were observed due to the presence of PO and POC groups . The results confirm that Am‐PAN‐ g ‐GMA was successfully reacted with phosphorous acid to obtain flame‐retardant PAN fabric.…”

“…It was found that phosphorus acid decomposed from the copolymer could catalyze the cyclization of the copolymers to form char; however, the greater the steric effect of the comonomer, the more difficult is the cyclization of the copolymer. Ren et al . synthesized the copolymer acrylonitrile– O,O ‐diethyl‐ O ‐allylthiophosphate and found the fire retardancy and the amount of char residue of the copolymer are increased.…”

Flame retardant modification of acrylic fiber with hydrazine hydrate and sodium ions

“…As a result, there is renewed effort to investigate and develop new classes of flame resistant acrylic fibers with nontoxic and smokeless. The phosphorus‐containing compounds and sulfur‐containing compounds then were introduced to acrylic fibers by copolymerization, blending, post‐treating and many other methods . Although, the phosphorus flame retardants are effective to improve the flame resistance of the acrylic fibers, the commercial use of the phosphorus flame retardants for acrylic fibers are few reported yet for many reasons, such as poor thermal resistance, complex architecture and high additive amount to acquire the good flame retardant property.…”

Preparation of phosphorus‐containing and nitrogen‐containing durable flame retardant polyacrylonitrile fabric via surface chemical modification

“…Modacrylic fiber is the only industrialized copolymerization fire retardant PAN fiber; nevertheless, modacrylic fiber is greatly restricted because the fiber can release toxic hydrogen halide and amounts of smoke during combustion. Halogen‐free comonomers can be used to copolymerize with acrylonitrile to improve the fire retardant performance of acrylonitrile polymers. However, the copolymerization flame retardant method also has some defects, such as higher synthetic cost, difficulty of copolymerization with acrylonitrile, and poor spinnability of the fire retardant acrylonitrile copolymers .…”

“…Halogen‐free comonomers can be used to copolymerize with acrylonitrile to improve the fire retardant performance of acrylonitrile polymers. However, the copolymerization flame retardant method also has some defects, such as higher synthetic cost, difficulty of copolymerization with acrylonitrile, and poor spinnability of the fire retardant acrylonitrile copolymers . Plasma grafting is a relative complex and difficult technique to operate, which limits the application of this technique to some extent.…”