Factory sales expandable polymeric beads Sheet Sandwich Panels STMMA Slab board for Lost form casting           The Advantage of using the STMMA instead of EPS Pure EPS: 100% polystyrene, pentane7% STMMA-FD:90%polystyrene+10%MMA, pentane>7% Decomposition and gasification chemical formula when pouring metal melt: EPS: C8H8=8C+4H2 STMMA:C5O4H8=3C+2CO2+4H2 From the formula, you will see why residues are more in EPS. And whatever additive you added to EPS, it wont change the main formula. Formula Solutions: 1.) STMMA series are focused on carbon rising defect in castings and with less residues, low dissolution temperature 2.) The STMMA-FD series have great advantages in solving fold defect by aluminum casting and applications in iron castings having excessive lustrous carbon, porosity defect solved. *Typical Application means we have tested in this kind of metal, metals beyond that are according to be actually used.