Alloying synergistic flame retardant effect improving fire resistance and mechanical properties of polyamide 6

Abstract

The alloying synergistic flame retardant effect was studied by using polyetherimide (PEI) and aluminum diethylphosphinate (ADP) for polyamide 6 (PA6), which can endow PA6 composites with excellent mechanical properties and flame retardancy simultaneously. On the one hand, because the molecular structures of PEI and PA6 are similar, adding PEI with PA6 can form PEI‐PA6 alloy by the hydrogen bond effect and nice homogeneous phase, which can endow PA6 composites with excellent mechanical properties. On the other hand, the test results of flame retardancy show that 9ADP/10PEI‐PA6 composite can obtain higher LOI value (LOI = 31%), and excellent flame retardant rating (UL94 V‐0) with 9%ADP and 10%PEI. From the results of cone calorimetry test, the pk‐HRR and THR of 9ADP/10PEI‐PA6 are reduced by 24.4% and 24.7%, respectively, compared to PA6, and higher char residue rate was obtained, which shows that ADP combined with PEI‐PA6 alloying exerts an excellent flame retardant synergistic effect. Through the study of flame retardant mechanism found that ADP works together with PEI can effectively increase the quenching effect in the gas phase, promote thermal stability, and delay the decomposition process of PA6 matrix during the combustion process. Meanwhile, it also increases the char yield to exert a synergistic effect in the condensed phase by ADP/PEI‐PA6. The residual char rate reached 36.6%, higher than neat PA6 about 4.6 wt.%. Thus, the alloying flame retardant method using ADP/PEI‐PA6 can endow PA6 with better flame retardancy and more excellent mechanical properties. Importantly, it provides a new direction for developing high‐performance halogen‐free flame retardant materials.

A key role of a bio‐based charring‐coupling agent in flame retardant and anti‐dripping performance of polyamide 6/aluminum diethylphosphinate

“…Therefore, it is difficult to be dispersed evenly in PA6. In addition, the interfacial adhesion between ADP and PA6 is weak, which will deteriorate the mechanical performance of PA6 blends 20,21 . With the efforts of researchers, two effective methods are put forward to solve these problems.…”

“…In addition, the interfacial adhesion between ADP and PA6 is weak, which will deteriorate the mechanical performance of PA6 blends. 20,21 With the efforts of researchers, two effective methods are put forward to solve these problems. One is the surface modification of ADP, 22 and the other is the addition of chain extender into PA6/ADP blends.…”

The effect of reinforcement aspect ratio on the performance of PA66 composites with recycled carbon fiber and upcycled graphene nanoplatelets: An interface characterization from process to modeling

“…The incorporation of micro and nanoscale additives into PAs to increase the mechanical properties while maintaining the overall weight became an important research subject. [15][16][17] Mainly; SiO 2, 18 clay, 19 calcium carbonate, 20,21 and carbonaceous materials such as carbon nanotubes, 22,23 carbon fiber (CF), 24 carbon black (CB), 25 exfoliated graphite, 26 and lately graphene 27 and graphenerelated materials 28,29 are being used to enhance the mechanical properties of polymers while maintaining the desired weight. Nevertheless, several challenges remain for the incorporation of such small-scale additives into the polymer matrix.…”

Ultrahigh compressive strength and heat resistance of polystyrene/polyphenylene oxide foams of supercritical carbon dioxide foaming

“…The resulting polymer is expected to achieve better performance owing to the introduction of another secondary component into the polymer matrix. [10][11][12][13][14] Zhou et al 15 used SBS to modify PS. Despite a small decrease in rigidity, the impact strength and elongation at break were considerably improved.…”

“…Polymer blending is a widely used method for developing new materials with desirable combinations of properties. The resulting polymer is expected to achieve better performance owing to the introduction of another secondary component into the polymer matrix 10–14 . Zhou et al 15 used SBS to modify PS.…”