Flame-retardant compounds with filling levels of up to 70 percent

Nowadays, mainly halogen-free flame retardants – such as Al2(OH)3 or Mg(OH)2 – are used in the production of flame-retardant compounds. Depending on requirements, filling rates up to 70% are necessary. Such high filling levels are only possible thanks to the flexible setup of co-kneaders.

Moreover, the incorporation of these additives is reliant on precise temperature control. As high filling rates lead to stiffening of polymer melts – the viscosity increases – one tends to aim for high process temperatures. However, such temperatures are potentially problematic in the context of halogen-free flame retardants because the active substances undergo chemical decomposition at high temperatures, thereby eliminating the flame-retardant effect.