Fluorine containing self‐crosslinking acrylic latexes with reduced flammability and their application as polymer binders for heterogeneous cation‐exchange membranes

Abstract

In this study, self‐crosslinking core–shell latexes comprising copolymerized perfluorethyl groups and a novel flame retardant based on phosphazene derivative were prepared by the semi‐continuous non‐seeded emulsion polymerization of 2,2,2‐trifluorethyl methacrylate, methyl methacrylate, butyl acrylate, methacrylic acid, and hexaallylamino‐cyclo‐triphosphazene as main monomers. For interfacial crosslinking, diacetone acrylamide was copolymerized into the shell layer of latex particles to provide sites for subsequent reaction with adipic acid dihydrazide. The heterogeneous cation‐exchange membranes were obtained by dispersing commercial strong acid cation‐exchange resin powder in the latex binder and casting the mixture followed by keto‐hydrazide crosslinking reaction. It was found that the increased concentration of fluorine atoms and phosphazene units in the macromolecular structure of interfacially crosslinked emulsion polymers resulted in a significant enhancement of their flame resistance and shape stability in aqueous environment. Moreover, the easily prepared heterogeneous cation‐exchange membranes based on latexes with higher amounts of fluorine and phosphazene units were shown to exhibit satisfactory physicochemical and electrochemical properties. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45467.

Synthesis of Phosphazene-Containing, Bisphenol A-Based Benzoxazines and Properties of Corresponding Polybenzoxazines

“…Phosphazenes also belong to the class of organo-inorganic compounds [ 13 ], the presence of which in polymers lowers combustibility [ 14 ] and increases heat resistance and degradation temperature [ 15 ]. Phosphazenes have advantages not only in comparison with unsafe halogen-containing flame retardants, but also in comparison with conventional phosphorus-based flame retardants [ 16 , 17 ] Functional phosphazenes contribute not only to reduced flammability, but may also be used to adjust the mechanical properties of the resulting thermosets [ 18 , 19 ], which make them one of the most promising halogen-free flame retardants. Phosphazene-containing benzoxazines synthesized in [ 20 , 21 , 22 , 23 ] form high fire resistance compositions during polymerization due to the synergistic effect of phosphorus and nitrogen atoms.…”

Synthesis of Resorcinol-Based Phosphazene-Containing Epoxy Oligomers

“…Thus, functional phosphazenes increase fire resistance [20], thermal stability, char yield [21], and tensile strength [22] of polyurethanes, as well as hardness and hydrophobicity of coatings based on them [23]. Self-crosslinking acrylic latex, which was obtained via an emulsion polymerization of 2,2,2-trifluoroethyl methacrylate, methyl methacrylate, butyl acrylate, methacrylic acid, and hexakisallylaminocyclotriphosphazene, exhibited improved stability, physico-chemical, electrochemical and properties [24]. …”