Modification of ADP/A-SEP Complex on EVA/MPE Cable Composites
A-SEP was prepared by surface treatment of sepiolite(SEP)with vinyltriethoxysilane(A151).The complex of A-SEP and aluminum diethylhosphinate(ADP)was used as flame retardant for ethylene-vinyl acetate copolymer(EVA)/metallocene polyethylene(MPE)cable composites.The effects of the composition of ADP/A-SEP on the tensile properties,flame retardancy,and processability of EVA/MPE cable composites were determined.The results show that ADP can significantly improve the flame retardancy of EVA/MPE cable composites,but it has obvious negative impact on the tensile properties.A-SEP has a good synergistic flame retardancy with ADP and can improve the tensile properties of EVA/MPE cable composites at the same time.The tensile strength and elongation at break of EVA/MPE cable composites are 11.43 MPa and 689%respectively.The limiting oxygen index(LOI)reaches 32%,and the initial thermal degradation temperature and carbon residue rate are352.89℃and5.75%,respectively,and the volume resistivity is 2.63×103 Ω·cm.In addition,when the addition of A-SEP is less than 3%,it has little effect on the processing fluidity of EVA/MPE/cable composites.