HT-3285 is PS based additive flame retardant master batch, gives the benefits of low dosage, easy foaming, easy extrusion, uniform dispersion, nice compatibility in XPS and high efficient flame retardancy, can be used in various extruders. As granule master batch, HT-3285 is very easy to be mixed with PS base material to get consistent fire retardancy; A nice advantage is to overcome the corrosion to the mould and extruder barrel so as to prolong the machines service life, moreover, it greatly shorten the extruder washing time to 1-2 hours to greatly improve the production efficiency.