Styrene polymerization process

Claim 1

METHOD OF POLYMERIZING STYRENE COMPRISING FORMING A STABLIZED AQUEOUS SUSPENSION CONTAINING STYRENE AS A SOLE POLYMERIZABLE MONOMER, INTIMATELY ADMIXING THEREWITH A CATALSYT COMBINATION CONSISTING OF 0.07-0.11% T-BUTYL PERBENZOATE AND 0.11-07% BENZOYL PEROXIDE, SAID PERCENTAGES BEING BASED ON THE WEIGHT OF STYRENE MONOMER IN THE SUSPENDED MASS, HEATING THE CATALYST-CONTAINING MASS TO A TEMPERATURE OF ABOUT 100* C. IN ABOUT AN HOUR AND MAINTAINING THAT TEMPERATURE FOR ABOUT TWO HOURS, THEREAFTER HEATING SAID CATALYST-CONTAINING MASS TO A TEMPERATURE OF ABOUT 115* C. IN ABOUT ONE-HALF HOUR AND MAINTAINING THAT TEMPERATURE FOR ABOUT TWO HOURS, AND THEREAFTER HEATING SAID CATALYST-CONTAINING MASS TO A TEMPERATURE OF ABOUT 135* C. IN ABOUT ONE-HALF HOUR AND MAINTAINING THAT TEMPERATURE FOR UP TO ABOUT ONE HOUR, WHEREBY THE FREE RADICAL CONCENTRATION OF SAID CATALYSTCONTAINING MASS IS PERMITTED TO INCREASE ONLY BY A VERY SLIGHT AMOUNT DURING THE SUCCESSIVE HEATING STAGES AND SUBSTANTIALLY COMPLETE POLYMERIZATION IS EFFECTED DURING THE FINAL HEATING STAGE.