TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Suspending Agent: The suspending agent system is selected from finely divided tricalcium phosphate and an anionic surfactant.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Flame Retardant: The flame retardant is selected from hexabromocyclododecane, 2,4,6-tribromophenyl allyl ether, dibromoethyl dibromocyclohexane, tetrabromocyclooctane, and tetrabromophenol A bis (allyl ether). The aqueous suspension comprises 0.2-2.5 wt.% of the flame retardant.Preferred Peroxide: The organic peroxide used in the decomposition has a half-life of greater than 2 hours at 100degreesC, and comprises 0.01-0.40 wt.%.Preferred Blowing Agent: The blowing agent is selected from butane, n-pentane, isopentane, cyclopentane, hexane, carbon dioxide and/or fluorinated hydrocarbons.    TECHNOLOGY FOCUS - POLYMERS - Preferred Polymer: The vinyl aromatic polymer has a molecular weight of 170,000-320,000 and a bead size of 100-600 microm, most preferably 250-425 microm. The vinyl aromatic monomer is styrene. EXAMPLE - Water (226 lbs) and styrene (226 lbs) were added to a reactor and stirred at 160 RPM. TCP (217 g), Nacconol (TM) (1.22 g), Polywax 1000 (TM) (205 g), HBCD (TM) (718 g), benzoyl peroxide (75%, 379 g), DiCup (TM) (308 g) and t-butyl peroxy-2-ethylhexyl carbonate (113 g) (TBEC) were added then added.    The reactor was heated from room temperature to 194 degreesF and kept at this temperature for 6 hours. At 5 hours and 45 minutes, water (18.1 lbs), TCP (205 g) and Nacconol (TM) (1.29 g) were added and the reactor heated to 203 degreesF, and a mixture of n-pentane (14.4 lbs) and iso-pentane (3.6 lbs) added over a period of 70 minutes at a rate of 1 lb/4 minutes.    The reactor was heated to 262degreesF at a rate of 1degreesF/minute and kept at this temperature for 2 hours and 15 minutes. The reactor was then cooled to 100degreesF and the contents emptied into a batch out tank containing water and HCl. The contents were acidified to a pH of 2.0 to remove TCP. The beads were dried by passing them through a dryer and screened to remove any agglomerated beads. Each hundred pounds of dry beads were then treated with silicone oil (10 g).    EPS box patterns were molded from the EPS beads. The EPS parts were conditioned and then dipped into a ceramic coating. After drying, the parts were glued in clusters to a sprue and then placed in a flask. Sand was compacted around them. Aluminum 319 alloy was poured into the patterns at 1350degreesF and the parts then examined for folds.