Be the Supervisor in Envionment friendly Flame-Retardant Materials

Finding


Novel flame-retardant Polyamide6/Melaminecyanurate-alpha-zirconiumphosphate(PA6/MCA--ZrP)compositeswereprepared via the incorporation of the modified MCA (MCA-α-ZrP) into PA6.

MCA-α-ZrP were synthesized through the self-assembly of α-ZrP, Melamine (ME), and cyanuric acid (CA) molecules.

The results of differential scanning calorimetry (DSC) and X-ray diffraction (XRD) showed that the incorporation of enough α-ZrP (30wt% MCA) caused the increased crystallinity of PA6 and tended to form γ phase. 

The thermogravimetric analysis (TGA) and heat distortion temperature (HDT) test illustrated that the α-ZrP could increase the residue and HDT values of PA6/MCA and showed a synergistic effect with MCA.

The combination of MCA and α-ZrP caused the enhancement of vertical burning test (UL-94) rating.

Cone calorimeter test (CCT) gave clear evidences that PA6/MCA-10α-ZrP composites with low heat release rate (HRR), low total heat release (THR), and high amounts of char residues after combustion compared with PA6/MCA and PA6/MCA-30α-ZrP.

What is more,excellent mechanical properties were kept even though MCA and α-ZrP were dispersed not as good as expected.

Experimental

Results and Discussion

 

Conclusion

MCA-ZrP were synthesized by self-assembly of ME and CA on the surface of α-ZrP powders. 

T_i of PA6/MCA and PA6/MCA-α-ZrP composites were increased compared to that of pure PA6.

The HDT values of PA6/MCA-α-ZrP with different α-ZrP contents were much higher than that of pure PA6 and PA6/MCA composites.

UL-94 results showed that the introduction of MCA enhanced flame retardancy to V- 2 rating and α-ZrP modified MCA to V-0 rating.

The cone calorimeter results showed PA6/10α-ZrP-MCA composites with lower HRR, lower THR, and higher amounts of char residues after combustion.

The incorporation of enough α-ZrP (30wt% MCA) caused the increased crystallinity of PA6 and tended to form γ phase.

SEM and TEM demonstrated that the dispersion of MCA and α-ZrP fillers was not asgood as expected, while it was not at the sacrifice of PA6’s mechanical properties because of its strong hydrogen 
bonds between α-ZrP and PA6.

These results indicated that α-ZrP and MCA had a significant synergistic effect to improve PA6’s flame retardancy ,crystallinity and  keep the excellent mechanical properties at the same time.

The R&D from Department of Chemistry & Chemical Engineering, Guangzhou University, Guangzhou 510006, China