Study on Property Change with a Fire Retardant Content in the Manufacture of Polymer Composites for Cable Sheath

Abstract

Four different polymer compounds were manufactured to make cable sheaths for the shipping industry. Two kinds of ethylene vinyl acetate (EVA) as the main matrix polymers and EVA-grafted maleic anhydride (EVA-g-MAH) as the coupling agent were selected for compounding with fire retardant, crosslinking agent, filler, plasticizer, and other additives. The properties of the four compounded materials were investigated with different contents of the fire retardant, silanecoated magnesium dihydroxide (S-MDH). In the rheology evaluation, the $t_{60}$ and ${\Delta}T$ values increased with increasing S-MDH contents. On the other hand, the tensile strength decreased with increasing S-MDH content due to a relative decrease in binder polymers. With increasing S-MDH content, fire resistance increased, but cold resistance showed no obvious enhancement due to the polar effect of vinyl acetate in EVA.

Figure 1. Curing curves of test samples.

Figure 2. The results of tensile test under room temperature.

Figure 3. The results of aging test.

Figure 4. The results of limited oxygen index test.

Table 1. Compound Formulation (unit: phr)

Table 2. The Results of Curing Test

Table 3. The Results of Mooney Viscosity

Table 4. The Results of Cold Resistance