In situ synthesized and dispersed melamine polyphosphate flame retardant epoxy resin composites

Abstract

The dispersion of flame retardants in polymer matrix has significant impact on the final properties of the final materials. Homogenous dispersion for additive type flame retardant powder in polymer melt or solution with high viscosity is a challenge all the time. In the present research, melamine polyphosphate (MPP) is employed to flame‐retard the epoxy resin (EP). Different from direct addition of MPP powder in viscous EP glue like conventional means, MPP is firstly synthesized by melamine and polyphosphoric acid in a good solvent for EP. Keeping fine and even dispersion of the produced MPP particles, EP prepolymer is added into the MPP containing solution. By this way, perfect dispersion of the flame retardant can be achieved both in the glue and the cured resin. A series of tests such as the particle size analysis, flammability evaluation, and mechanical properties tests are conducted to compare the MPP flame retardant EP obtained by this method and the conventional one. It shows that the in situ synthesis and compounding method can endow the MPP incorporated EP glue system with better homogeneity and stability, hence leading to higher flame retardancy and obviously improved mechanical performance of the final composite. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47194.

Flame‐retardant poly (ethylene terephthalate) enabled by a novel melamine polyphosphate nanowire

“…The XRD was employed to investigate the crystalline structure of MPP nanowires, and the relevant data were collected and shown in Figure B. As one could see, the distinct diffraction peaks at 16.5°, 17.8°, 18.7°, and 27.2° were sharp and strong, which were in accordance with the previously reported studies, demonstrating the successful synthesis of MPP nanowires …”

“…In addition, two characteristic peaks at 1163 and 1388 cm −1 corresponded to P═O and C–N in triazine ring structure, respectively. The vibration absorption of P–O group in P–O–H was observed at 1064 cm −1 , and the two absorptions at 962 and 878 cm −1 were associated with P–O–H and P–O–P groups in MPP nanowires …”

“…Melamine polyphosphate (MPP), an efficacious P–N flame retardant, is broadly applied in improving the flame retardance of poly (vinyl alcohol), polyamide 6,6, and epoxy resin because of its excellent thermal stability, low cost, and low smoke and toxicity . Previously reported studies have demonstrated that MPP can act both in gaseous and condensed phases.…”

“…[8][9][10][11] Melamine polyphosphate (MPP), an efficacious P-N flame retardant, is broadly applied in improving the flame retardance of poly (vinyl alcohol), polyamide 6,6, and epoxy resin because of its excellent thermal stability, low cost, and low smoke and toxicity. [12][13][14] Previously reported studies have demonstrated that MPP can act both in gaseous and condensed phases. In the condensed phase, phosphorous can accelerate the formation of compact carbon char through catalytic carbonization effect, which efficiently protects inner matrix from contacting to outside heat and oxygen, committing to higher flame retardance.…”

Mussel‐inspired polydopamine/polystyrene composites with 3D continuous structure and improved thermal, mechanical, and flame retarding properties

“…The construction of composites by adding flame retardants (FRs) into polymers is the most straightforward and effective method to address this issue. The organic FRs, including intumescent systems (containing a carbon source, an acid, and a blowing agent) and phosphorus‐based compounds, are the most frequently adopted additives in flame retarding composites as they can generate protective carbonaceous chars that prevent the inner substance from burning . However, a large quantity of organic FRs are needed to achieve the desired flame retardancy, which seriously affect the intrinsic thermal and mechanical properties of polymers.…”