Traditional Cable Filler

  • High density
  • Reduced capacitance due to higher relative dielectric constant
  • Easy to shrink when cool at low temperature

Cable Filler with Microsphere

  • Reduced weight
  • Decreased relative permittivity
  • Increased drop melting point
  • Volume contraction at cooling
  • High compressibility
  • Increased viscosity

Microspheres are successfully used in petrolatum cable filling compounds as it could reduce the dielectric constant and increases the drop melting point.

Effects of adding microspheres

Microsphere could reduce weight/density dramatically even adding small portion. For example, 1% dosage in weight, the density will drop down 20-30% depending on the true density of different grades of microspheres.

Most petrolatum has a high-volume shrinking at cooling and expansion at heating. A volume expansion of 5 percent between 20 and 65°C is normal. Front Microsphere will offer internal pressure in the cable, resulting in less shrinkage and less water penetration.

The microspheres can resist high filling pressures. The microspheres can be filled into small interspaces between the conductors since its high compressibility.


We are here to help. Our application team are ready to maximize the benefits of Waytop Microspheres in your application.