Aryloxyphosphazene-Modified and Graphite-Filled Epoxy Compositions with Reduced Flammability and Electrically Conductive Properties

Abstract

A method has been developed for producing an epoxy composition based on a low-viscosity epoxy-resorcinol resin, a phosphazene-containing curing agent, isophoronediamine, and thermally expanded graphite as a filler. The degree of cure and the absence of side reactions during the curing process were confirmed using IR spectroscopy. The influence of the content of phosphazene-containing curing agent and filler on the physico-mechanical properties of the composition, its fire resistance, and antistatic properties were studied. Using the UL-94 HB horizontal burning test, it was found that the addition of 10 and 20 wt. % phosphazene-containing curing agent (relative to isophoronediamine) reduces the burning speed by 10 times compared to a sample without phosphazene. The addition of a filler to a composition containing phosphazene reduces the burning speed by 25 times compared to a composition without phosphazene and imparts antistatic properties to the epoxy composition, as evidenced by the specific volume electrical resistance of the order of 101 Ohm·m. Phosphazene-containing curing agent had no statistically significant effect on specific volume electrical resistivity (p > 0.05). Tests of physico-mechanical and adhesive properties (tensile strength, compressive strength, water absorption, water solubility, abrasion resistance, and adhesive strength) of filled epoxy compositions with 10 and 20 wt. % phosphazene-containing curing agent demonstrated that these properties met the requirements for floor coverings in construction and parts of electrical devices.

Fragmentation Pathway of Organophosphorus Flame Retardants by Liquid Chromatography–Orbitrap-Based High-Resolution Mass Spectrometry

“…Organophosphorus flame retardants (OPFRs) are common polymer additives employed for flame retardation and plasticization [1][2][3]. In recent years, OPFRs and related degradation products and analogues have been commonly found in water [4], dust [5], sludge [6], and various foods [7][8][9][10][11], and are distributed worldwide [12][13][14].…”

Optimized Functionalization of Graphene Oxide for Enhanced Mechanical Properties in Epoxy Resin Composites

“…Cahit Orek et al [14] solved the problem of gold(I) N-heterocyclic monocarbene-adsorbing graphene as a drug nanocarrier via calculations. Studies have shown that graphene and its derivatives can effectively improve the mechanical properties of polymers, Anastasia Konstantinova et al [15] ascertained that the incorporation of a phosphazene-containing curing agent, coupled with thermally expanded graphite, markedly enhanced the fire resistance, as well as the physical and mechanical characteristics, of epoxy resin. However, it could only happen if graphene nanoplatelets were well dispersed in the polymer matrix [16][17][18][19].…”

Synergistic Effect of PBz/Epoxy/PCLA Composite Films with Improved Thermal Properties

“…Epoxy resins are used to produce composites with other polymers, due to their diversified properties such as ease of processability, enhanced physical and mechanical properties, good adhesion with other materials, resistance towards chemicals, and electrical insulation. Despite these admirable properties, they also possess high flammability and low fire resistance, which hinders the advantage of the final product [8][9][10]. Epoxy resins are well known for their versatility and compatibility with various polymers, making them ideal candidates for blending with PBzs.…”