Synthesis of a heat‐resistant DOPO derivative and its application as flame‐retardant in engineering plastics

Abstract

A star‐shaped DOPO derivative (GL‐3DOPO, P content 10.8 wt %) was synthesized through a two‐step reaction involving glycerol, acryloyl chloride, and DOPO. The derivative demonstrated a great improvement of thermal decomposition temperature increased to 360 °C from 194 °C (under N2 atmosphere), promoting its application in thermoplastics of high processing temperature. When blended with engineering plastics including PET, PBT, PC, PA6, and PA66 at a GL‐3DOPO loading of 25 wt %, all the compounds reached the UL94 V‐0 level and increased limit oxygen index (LOI). In PET system, LOI raised from 22.8% to 35.4% with P 2.5 wt % and passed the V‐0 test with only 0.8 P wt %. Compact char layers were found in the PET system after LOI test, suggesting that GL‐3DOPO acted both in gas and condensed‐phase mode. All results indicated that GL‐3DOPO could be a potential flame‐retardant for engineering plastics. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44892.

Flame Inhibition and Charring Effect of Aromatic Polyimide and Aluminum Diethylphosphinate in Polyamide 6

“…Thus, as an alternative to BFRs, the halogen-free flame retardant system has become the focus of interest. In current studies on PA6 with halogen-free flame retardant systems, research teams have mainly developed polyamide materials with high flame retardant performance by using the following four methods: (1) constructing an efficient flame retardant system by blending different components and utilizing the component synergistic effect [6,7,8,9,10,11,12,13,14]; (2) obtaining a new flame retardant system by bonding different flame retardant groups into one molecule [15,16,17,18,19,20,21]; (3) designing novel flame retardant chemical structures [22,23,24]; and (4) preparing intrinsically flame retardant polyamide [25,26]. However, traditional halogen-free flame retardants for polyamide, such as melamine polyphosphate (MPP) [27] and melamine cyanurate (MCA) [28], have been unable to meet commercial demands for improved physical-mechanical properties because of their low flame retardant efficiency.…”

A macromolecular halogen‐free flame retardant and its effect on the properties of thermoplastic polyesters

“…For PET, metal salts of dialkylphosphinates (eg, aluminum diethylphosphinate) are commercially available . Academic research focused on carbon nanomaterials, cyclotriphosphazene systems, and derivatives of DOPO (9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide) …”

“…7 Academic research focused on carbon nanomaterials, cyclotriphosphazene systems, and derivatives of DOPO (9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide). [12][13][14] During the last years, general problems with unintended release of additives of low molecular weight have led to the development of polymeric flame retardants. Due to their macromolecular structure, these systems are considered to be nonleeching, nonblooming, and nonbioaccumulative.…”

Phosphorus-Containing Flame Retardants from Biobased Chemicals and Their Application in Polyesters and Epoxy Resins

“…Xie et al melt blended GL-3DOPO with engineering plastics like PET, PBT, PA6, PA66 and PC. GL-3DOPO decreased the melting temperature and the glass transition temperature of the melt blended polymers [103].…”

“…A total phosphorus content of 0.5% can achieve a V-2 classification in UL94 vertical burning tests whereas total phosphorus contents from 0.8% to 2.5% result in a V-0 classification for GL-3DOPO in PET. For PBT a total phosphorus content of 1.5% was able to achieve a V-0 classification and from 2.0% up to 2.5% a V-0 classification was obtained [103].…”