The material and shape of electrical equipment must be carefully selected to ensure that no fire will be caused by the material under operating conditions. Among the many flame retardants, aluminum hydroxide (Grade ATH) is currently the most used. The increase in the use of this material is mainly due to the relationship between cost and benefits. Compared with other flame retardants, the main advantages of ATH are its low cost and low toxicity. It can also act as a flame retardant and smoke inhibitor at the same time. Under high temperature conditions, it will not release toxic or corrosive substances.

As a semi-reinforcing filler, ATH does not significantly increase the mechanical strength of the compound when incorporated into polymer materials. After surface treatment with silane and titanate, the ATH's reinforcing properties can be improved. When EPDM compounds contain different amounts of carbon black and ATH, physical and mechanical properties and electrical performance tests can be used to determine whether these compounds are suitable for use as insulation jackets for wires and cables.

When the amount of N330 carbon black is increased, the improvement effect is more significant. Obviously, the surface treatment only had a positive effect when the compound contained only ATH's sole filler. The hardness increases with the incorporation of the filler because all the compounds exhibit higher hardness values ​​than the pure rubber. However, this performance is neither affected by the amount of ATH nor by the ATH species.

When the polymer material is used as an insulating sheath for wires and cables, tear strength is an important indicator. If the tear strength is low, the possibility of occurrence of fine cracks will be increased, and once fine cracks occur, discharge will occur, and thus electrical breakdown and insulation failure will occur.