Flame retardant compound
Flame retardant compound
(OP)
Hi
Need a basic formulation for above mentioned compound .
Cost is the major factor here , so am looking at what the cheapest option would be to reduce the flammability of exsisting offspec compounds .
Article to be molded is a rubber impact for conveyor rolls .
TIA
Need a basic formulation for above mentioned compound .
Cost is the major factor here , so am looking at what the cheapest option would be to reduce the flammability of exsisting offspec compounds .
Article to be molded is a rubber impact for conveyor rolls .
TIA





RE: Flame retardant compound
RE: Flame retardant compound
RE: Flame retardant compound
At present we are using offcut rubberlining rubber , predominantly 45 - 50 shore hardness . To this we add Aluminium Trioxide , Zinc Borax and paraffine wax .
The spec given is that a 2mm thick strip sample needs to extinguish itself within 5-7 seconds after being lit . The above chemicals achieve the result required but add quite a cost to the compound ,and also the amounts needed affect the hardness drastically .
Hardness required is between 65 and 70 shore .
RE: Flame retardant compound
You should replace the paraffin wax and replace it with 5 or 6phr of either chlorinated paraffin wax or tricresyl phosphate.
I would not want to guess what else is in your base compound but you should remove anything that is flammable such as mineral oils. Since your desired hardness of 60 - 65 is above what you are finding now, do not replace any oil removed. If the hardness is still on the low side, add ground or precipitated whiting, or hard clay.